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INDEX Aquaculture Magazine Volume 43 Number 1 February - March 2017


on the

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Global Blue Technologies Approaching an Aquaculture Industry Differently. INDUSTRY NEWS

Aqua-Spark Announced its Final Investment for 2016. Blue Ridge Aquaculture Announces an Expansion Plan in Henry County.

New Antiviral Drug with Great Potential for Aquaculture. Volume 43 Number 1 February - March 2017


Marine Fish Farm Project in Cambodia Progresses.

Editor and Publisher Salvador Meza Editor in Chief Greg Lutz Editorial Assistant María José de la Peña


Aller Aqua Group Invests 10 Million USD in a Tilapia Feed Factory in Zambia.

Editorial Design Francisco Cibrián Designer Perla Neri Marketing and Communications Manager Alex Meza Marketing & Sales Manager Christian Criollos


News from the ADAAP





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Notice of Change to Federal Rule Regarding Access to Antibiotic Drugs and Consequences for Fish Hatcheries. Recent news from the NAA.

Potential drivers of virulence evolution in aquaculture.

Sales Support Expert Gustavo Ruiz Business Operation Manager Adriana Zayas

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R&D Centers





Selective Breeding for SPF Giant Freshwater Prawn.

Eastern Little Tuna, Euthynnus affinis, (Cantor, 1849): Reproductive Maturation within One Year of Rearing in Land-based Tanks.

Performance of Litopenaeus vannamei postlarvae Reared in Indoor Nursery Tanks Under Biofloc Conditions at Different Salinities and Zero Water-Exchange.

An Overview of Oceanic Institute of Hawaii Pacific University.

Aquaculture Industry Shows Talent in Developing Fish-Free Feeds.

It’s good to promote the consumption of fish and seafood, but it’s also important to promote and ensure production.

columns FISH HEALTH, ETC TILAPIA & Genetics and Breeding Aquaculture Stewardship Council AQUAFEED NUTRITION Aquaculture Engineering SALMONIDS shellfish corner AQUAPONICS the fishmonger the long view Perspective and Opinion

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Upcoming events advertisers Index

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Editor´s comments

Aquaculture in the coming decades… are we missing something here? Clutch at the moments, as I may… They elude my grasp… Each is my

enemy… It rejects me… Signifying a refusal to become involved… E.M. Cioran, ‘The Fall into Time’

By C. Greg Lutz


nyone who keeps up with the world today might have good reason to suffer from a bit of “chronophobia” – the fear of the future. Actually, chronophobia refers to a persistent and irrational fear about things yet to come and the fact that we are being dragged along toward the future with every breath. There are some, perhaps many, among us who would argue that at this point in history a fear of the future is completely rational, and that it probably should be a persistent factor in our thought processes. However, it seems few of us suffer from chronophobia when it comes to aquaculture. We constantly highlight the fact that the population of the planet will reach 9 billion souls in the near future, and it will be up to aquaculture to fill the gap in protein supplies. But, I cannot for the life of me recall anyone ever adding “there is NO WAY aquacul4 »

ture can meet the demands that will be placed on it.” Quite the contrary, everyone involved in our industry seems ready to roll up their sleeves, take a deep breath, and figure out how to solve this problem. So, what strategies have the most promise? There are those who champion low-input approaches. Clearly there are advantages to keeping stocking densities and effluent discharges at minimal levels, and letting nature do most of the work for us. But available space for such enterprises will probably be at a premium in the coming decades. On the other hand, there are those who believe that intensive and super-intensive approaches will be necessary to generate the volumes of product we will be called upon to deliver. The inescapable component of this approach involves energy consumption. Will energy eventually be more expensive, or more available through renewable sources?

Both low-input and intensive production approaches will have to cope with the unavoidable outcomes that accompany the culture practices being utilized: environmental impacts, user group conflicts, genetic alterations of production stocks and pathogens, socioeconomic issues and, perhaps worst of all, politics at local, national and international levels. The song keeps playing (on LP, or cassette, or 8-track, or CD, or MP3 or who knows what’s next), but nowhere in these discussions do we actually confront the possibility: what if aquaculture, despite all its comparative efficiencies in the production of edible protein, CAN’T produce all the fish we will need? Just something to ponder as we contemplate the inexorable march of time. Dr. C. Greg Lutz has a B.A. in Biology and Spanish by the Earlham College at Richmond, Indiana, a M.S. in Fisheries and a Ph.D. in Wildlife and Fisheries Science by the Louisiana State University. His interests include recirculating system technology and population dynamics, quantitative genetics and multivariate analyses and the use of web based technology for result-demonstration methods.





Announced its Final Investment for 2016 Netherlands. – During the last days of 2016, Aqua-Spark, the first investment fund for sustainable aquaculture, announced its final two investments for the year: LoveTheWild, ready to prepare frozen seafood kits, and Indian Ocean Trepang, a sustainable sea cucumber farming operation. The U.S.-based company LoveTheWild (LTW) is Aqua-Spark’s first foray in the consumer market. LTW is currently sold in almost 600 stores nationwide. With funding from Aqua-Spark, the company’s seafood kits will become available in more stores and make a quick and smooth transition from 60 % farmed and 40 % wild to 100 % sustainable farmed fish. “Our goal is not just to offer sustainable seafood, but to make it the most exciting consumer protein in demand. In addition to a strategic investment, Aqua-Spark brings in-

dustry expertise, which when combined with our product, brings us one step closer to changing the way Americans think about farmed seafood,” explained Jacqueline Caludia and Christy Brouker, co-founders of LoveTheWild. On the other hand, the Madagascar-based company Indian Ocean Trepang (IOT) is the exclusive global licensee for an innovative patent on in-vitro fertilization of Holothuria scabra sea cucumber species. This, combined with Aqua-Spark’s investment of $2.75 million, has positioned them as the world leader in growing sea cucumbers – an ocean species that is a delicacy in Asia and also works as a filtering organism for fish farms. “An investment in Indian Ocean Trepang is an investment in the future of sustainable fish farming and the survival of this species,” explained Mike Velings

Indian Ocean Trepan is an innovative sea cucumber operation located in Madagascar. (Source: Indian Ocean Trepang)

and Amy Novogratz, co-founders of Aqua-Spark. “They are at once helping to protect an endangered marine animal and providing a sustainable filtering method for fish farms, while also creating job opportunities in key markets. We are thrilled to work with a company that causes such a great impact, and to connect them with our network of farms and technologies.”

Blue Ridge Aquaculture Announces an Expansion Plan in Henry County United States. – The aquaculture firm will invest $3.2 million USD to expand its operations in Henry County. Blue Ridge Aquaculture, located near Martinsville, Virginia, is the world’s largest producer of tilapia using indoor recirculating aquaculture systems (RAS). Virginia has positioned itself as the third-largest seafood producer in the US and the largest on the Atlantic Coast. In addition, the state is ranked 10th nationally in aquaculture. Part of the investment is financed by the Governor’s Agriculture and Forestry Industries Development (AFID) Fund administrated by the Virginia Department of Agriculture 6 »

and Consumer Services (VDACS), which approved a $50,000 USD grant, and Henry County matched it with local funding. The Virginia Tobacco Region Revitalization Commission awarded a $25,000 USD grant for the project too. Additionally, Blue Ridge Aquaculture is receiving a Real Property Investment Grant through the Virginia Enterprise Zone Program, administered by the Virginia Department of Housing and Community Development. “The success of Virginia’s agriculture industry is a testament to the diversity and quality of its products, as well as its outstanding reputation in the global economy,” Governor Terry McAuliffe said in a statement. “I applaud Blue Ridge Aqua-

culture’s continued investment in Henry County and its expansion speaks about the high-quality seafood and marketplace success of the company. We will continue to support projects and products that diversify our agriculture industry; to build a new economic situation for Virginia and contribute to the Commonwealth’s reputation as the best place to do businesses around the world.”

New Antiviral Drug

with Great Potential for Aquaculture United States. – Recent research published in the Journal of Virology of the American Society of Microbiology outlines the development of an antiviral drug with the potential to inhibit viruses of great importance for aquaculture. The name of this compound is LJ001, and it also works as a vaccine in fish. LJ001 proved to reduce IHNV (Infectious Hematopoietic Necrosis Virus) infections in fish cells within test tubes and in experiments in infected rainbow trout fry – in a dose and time dependent manner. It also reduced the transmission of the virus, but did not completely block it at established antiviral levels. LJ001 disables the virus by incorporating itself into the viral membrane in between the lipid layers. In the presence

of light, photons hit the drug generating oxygen radicals, which react with the membrane lipids, altering them chemically in a way such that the viral membrane can no longer fuse with the membranes of host cells. This prevents the virus from entering the host cells and replicating. Hector Aguilar-Carreno, PhD, Associate Professor in the Paul G. Allen School for Global Animal Health, Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, shared the unusual history behind the development of LJ001. Some years ago, a drug that could inhibit several enveloped viruses was discovered, with the peculiarity that it could only kill viruses in the presence of light. Aguilar-Carreno found

an advantage in this “limitation”, since its application in aquaculture was ideal. Later on, they tested the drug with IHNV. For now the research continues. Currently, the research team is trying to use LJ001 to deactivate the virus that can then be used as a vaccine for fish to protect them from future viral infections. For the full report, please visit: www.




Marine Fish Farm Project in Cambodia Progresses Cambodia. - In May 2016, the Norwegian company Vitamar AS Co announced plans to invest $24 million USD into a large-scale marine fish farm in Preah Sihanouk province in Cambodia. The fish farm is planned for producing grouper, sea bass and other valuable aquaculture species. The project is planned to be implemented in stages over a period of eight years. In the first two years, investment will focus on infrastructure (construction of a coastal facility and egg-hatchery site), and staff training. Over the next three years, production is expected to increase from

1,000 to 2,000 tonnes, as well as expansion of distribution and exports. Subsequently, the company would work on increasing the production to 3,000 tonnes and corresponding market expansion. The project’s managers estimate it will generate at least 200 direct jobs locally. Vitamar AS Co has ventured into similar projects in Vietnam, Chile, Scotland, Greece, Spain and Norway. At this point, the proposal is being reviewed by the Development Council of Cambodia for approval. Since Cambodia hasn’t established a marine aquaculture policy, it may take some time to resolve. Tourism

in Preah Sihanouk province has increased over the years and further development is expected: 2 million visitors per year in 2020. Hence, it is of utmost importance to produce food locally to meet this growing demand.

Aller Aqua Group

Invests 10 Million USD in a Tilapia Feed Factory in Zambia Zambia. – Aller Aqua Group’s expansion plan in Africa continues on the right track. The Danish company is currently building a factory in Siavonga, Zambia for the production of high quality extruded fish feed for aquaculture, which will start its operations by September 2017, and will have a production capacity of 50,000 tonnes annually and is expected to be the most technically advanced fish feed factory in Southern Africa. Aller Aqua Zambia has a promising future, since the first big client is already secured. The company has made a sales agreement with Yalelo Limited, which is the leading seafood firm and the second largest aquaculture firm in Africa. Yalelo plans to grow its production of tilapia to 30,000 tonnes in Zambia in the following years, which consequently requires a reliable supply of feed. 8 »

In 2015, the company built a factory in Egypt. Currently, in addition to the construction of the factory in Zambia, the company is expanding its capacity in Egypt with a third production line. “With the investment in Zambia, we will be the market leader in Africa in terms of modern and environmentally friendly fish feed for aquaculture. This will enable us to expand our sales not only in Zambia, but also in the surrounding countries. In recent years, Aller Aqua Group has opened sales companies both in Nigeria, Ghana and Kenya. The African market will, without a doubt, grow significantly in the coming years. The number of inhabitants is rising quickly and the population will need healthy food, which is high in protein. Fish farming and locally produced fish are part of the solution, and fish farming can further help people to get a livelihood and escape poverty. In

Zambia, approximately 95 % of the raw materials we will use comes from the local market, which is a great advantage,” said Henrik T. Halken, Vice-President of the Group (CPO).



News from the ADAAP

Notice of Change to Federal Rule Regarding Access to Antibiotic Drugs and Consequences for Fish Hatcheries

The FDA has issued a new rule that all antibiotics will be accessible only with veterinary oversight. This rule was adopted to address concerns related to the development of antimicrobial resistance.

Starting January 1, 2017: 1. All in-feed treatments of FDA approved antibiotics will require a Veterinary Feed Directive (VFD). These include Aquaflor, Terramycin 200 for Fish, Romet 30, and Romet TC. The FDA prohibits end-users from top-coating antibiotics on medicated feed. Products that were previously “over the counter” will no longer be used extralabel as prescribed by a veterinarian as this type of use of a VFD drug is now prohibited. 2. All immersion treatments with FDA approved antibiotics will require a veterinary prescription. This includes products like Oxymarine, 10 »

Pennox343, and Terramycin 343 for marking skeletal tissue of fish. The new rule does not apply to approved drugs that are not antibiotics (if used according to the label), such as Halamid Aqua (chloramine-T), 35 % Perox Aid (hydrogen peroxide), Parasite–S (formalin); drugs used under a compassionate INAD authorization; or low regulatory priority/deferred regulatory status drugs. What does this mean for you? You’ll need to establish a valid veterinarianclient-patient relationship (VCPR) and work with your veterinarian and local fish health specialist to obtain prescriptions/VFDs for the affected

drugs. Be aware that the definition and requirements of a valid VCPR vary by state. We anticipate challenges relative to timely coordination with veterinarians and treatment application. Experience with Aquaflor (always a VFD drug) suggests that VFDs can be issued and medicated feed acquired to allow treatment within 2-3 days of diagnosis. However, efficiency of this process is going to be highly dependent on veterinarian availability and laying the groundwork ahead of time may avoid lengthy delays to fish treatment. If a hatchery does not already work

with a veterinarian, consult with a fish health center to identify qualified veterinarians. Working with the veterinarian and fish health specialist, develop a plan for rapid disease diagnosis, prescription/VFD issuance and drug acquisition to ensure prompt treatment of sick fish. Be aware that keeping an inventory of drug/medicated feed on site for immediate treatment following diagnosis will be difficult or prohibited. Unused product on hand after January 1, 2017 must be disposed of in an appropriate manner. This new rule also affects those that use oxytetracycline products to mark skeletal tissue of fish and starting Jan 1, 2017, a veterinarian will need to prescribe this treatment. At this time, there may be some uncertainty relative to the use of antibiotics for this purpose and whether such use falls within this new rule. AADAPs interpretation is that marking fish with oxytetracycline hydrochloride will require a veterinary prescription. If you have further questions, please contact your Fish Health Center or the Aquatic Animal Drug Approval Partnership Program.

FDA grants greater flexibility in using VFD drugs The FDA recently sent out a letter that should please most folks involved in aquaculture—veterinarians will now have more flexibility in directing treatment of fish. The staff at AADAP have condensed and translated some of the more technical jargon in this letter into layman’s terms for ease of understanding. Although originally prohibited, FDA is now making exceptions for the extralabel use of Veterinary Feed Directive (VFD) drugs in fish and other minor species under certain conditions. This means that a veterinarian will be able to write a prescription for use of a VFD drug for the following: 1. Use in species not listed in the labeling,

2. Use for indications (disease or other conditions) not listed in the labeling, 3. Use at frequencies or routes of administration other than those stated in the labeling, and 4. Deviation from the labeled withdrawal time based on these different uses. The letter doesn’t state that it is legal to prescribe extralabel use of VFD drugs. Rather, the letter is intended to provide information to FDA field inspectors to let them know that their agency will no longer take enforcement action against the parties involved in extralabel use (aka, enforcement discretion for a veterinarian writing a prescription for extralabel use of a VFD drug). This is especially timely good news, since all in-feed antibiotics became VFD drugs as of January 1, 2017. For aquaculture, this means products such as Terramycin 200 for Fish (active ingredient, oxytetracycline dihydrate; VFD drug no longer available over-the-counter) and Aquaflor (active ingredient, florfenicol; always a VFD drug). By granting greater flexibility to veterinarians, FDA is helping to make safe and effective treatments more accessible to fish and fish culturists in need.

Saved by the Paperwork! By Jim Bowker, AADAP program Every year, it seems we are responsible for filling out and filing more and more paperwork. Over the years, it has become second nature and we document and file pretty much everything so that it can be readily retrieved at a later date. It’s critical that we do so, to be ready for audits by FDA investigators, Institutional Animal Care and Use Committees, and others who may need to inspect our paperwork. We know that inspections are part of the routine in our line of work. Whether it’s providing documentation to an inspector or tracking down a forgotten experimental detail for a manuscript, we rely on our complete, well-organized

documentation. Time and again, we have been saved by the paperwork! What about you? Is your paperwork sufficiently in order to be your safety net? Recently, an FDA investigator made a visit to a state agency fish health office for a compliance check and needed to see the agency’s VFD paperwork and associated fish health diagnostic reports for the last two years. The paperwork was retrieved and the investigator found everything to be in order, but the fish hatcheries that had applied the drugs and the veterinarian who signed off on their use would be visited within the next 24-48 hours to cross-reference the cases and make sure that they had also filed the appropriate paperwork. Although everything checked out with the hatcheries and the veterinarian’s files, the process definitely generated some temporary anxiety. Kudos to the fish health office for keeping copies of the appropriate VFD paperwork. The regulations had simply stated that the completed VFD forms would need to be kept by the feed mill, the veterinarian, and the hatchery but nothing about the fish health lab involved in the initial diagnosis. How can you be prepared for a visit from a FDA investigator? Maintain complete VFD files, including a copy of the diagnostic report and VFD documentation, in a centralized location. Although the fish health office mentioned above had all the right documentation on file, the cases were filed by an individual hatchery. Consequently, somebody had to go through all their hatchery file folders to find the paperwork. They’ve now chosen to build in a little redundancy and keep two copies of all pertinent paperwork: one set filed in the appropriate hatchery file and the duplicate filed in a centralized VFD file, organized by year. Hatchery managers should follow suit and create a centralized VFD file folder for duplicate copies for easy access during inspection. » 11


Recent news

from the NAA Up-date: Commercially Important Aquaculture Species Included in the Injurious Species Petition In our previous edition, we shared a note about a petition to list commercially important aquaculture species as “injurious wildlife,” presented by the Center for Invasive Species Prevention (CISP), in September 2016. As mentioned previously the listing of species like catfish and tilapia could significantly impact aquaculture industries in the U.S. Some updates of the CISP petition process are listed here: • The NAA has created an e-mail list to distribute updates of this issue going forward. Sign in to keep track of the petition process. • Recently, the Center for Invasive Species Prevention (CISP), withdrew the red swamp crawfish from consideration. With the caveat that this species may merit further analysis. • In November 2016, the American Farm Bureau Federation led an effort to develop a white paper entitled “Regulatory Improvement and Reform: a Priority for American Agriculture.” This document has been signed by a number of agricultural organizations. • The NAA made contributions to this paper and submitted an issue that describes the US Fish and Wildlife Service (FWS) as a regulator to overreach the Lacey Act and animal disease issues. • The NAA spoke about the 43 species in the CISP Injurious Wildlife petition at the fall meeting of the Aquatic Nuisance Species Task Force (ANSTF), which took place in Washington DC. The meeting was held to address prevention, management, control, eradication and public edu12 »

Among the commercially important aquaculture species included in the petition are three tilapias - blue, Mozambique and Nile.

cation in relation to aquatic nuisance species. The NAA also mentioned issues related to the errors inherent to the rapid screening methodology that FWS uses and the quality of the information in the resulting reports. Although noncommittal, the FWS did acknowledge receiving public comments on the petition, and appears to have started grasping the size and scope of the farms and businesses that produce the farm-raised species in the petition, pertinent state regulatory requirements, and the fact that these species do not pose a threat to the United States. • The NAA spoke before the ANSTF about the aquaculturists’ and distributors’ efforts, and the cost involved, in remaining current with state regulations when transporting live species across state lines. The Lacey Act supports state regulations by making it a federal crime if federal, state, tribal or local laws are broken while moving live species between states.  As a consequence, aquarium-species distributors must avoid delivering a species to

a state where that species is prohibited, and species´ identification must be accurate. The 50 states + Puerto Rico prohibit 2,356 live fish, reptiles, plants, amphibians and other species commonly sold to aquarium hobbyists.  Some states prohibit only one species, but Maine prohibits 1,871. The presentation was probably the first one to provide the ANSTF with in-depth information that drives home the point that states have regulations to prevent the introduction of nonnative species and that the federal agencies should defer to the states, rather than adopt nationwide prohibitions under the Lacey Act.  • The NAA has invited the FWS to present at a special session, tentatively titled “Lacey Act and Injurious Wildlife Listings,” during the upcoming Aquaculture America 2017 conference that will be held in San Antonio, TX, February 19-22, 2017.   • Meanwhile in Washington DC, the NAA met with the Pet Industry Joint Advisory Council (PIJAC) to discuss

The webinars were: • Aquaponics – How to Do It Yourself! • Mandatory Inspection of Fish of the Order Siluriformes • Labeling Requirements for Siluriformes Fish and Fish Products • What You Need to Know About Biosecurity • How to Design Your Biosecurity Plan • Recreational Fish Pond Management • The HACCP Approach to Prevent the Spread of Aquatic Invasive Species • U.S. Farm-Raised Finfish and Shellfish 101 • Regulatory Costs of U.S. Aquaculture Businesses • Branding Opportunities for Oyster Farmers • Seafood in the Diet: Benefits and Risks – Farm-Raised and Wild • Use of Veterinary Feed Directive Drugs in Aquaculture • Social Media: An Introduction for Successful Use • Fish Health: What You Need to Know as an Aquaculture Producer. To access these webinars, visit via your computer or mobile device, and select “webinars” from the menu. collaborative efforts to defeat the petition, stop or amend the use of quick screenings, and modify or withdraw factually inaccurate quick screening (ERSS) reports.  • The NAA presented the issue of the 43 species Injurious Wildlife petition via conference call to the California Aquaculture Association, who is developing a comment letter and is encouraging its membership to do so as well.

Update: U.S. Fish and Wildlife Service Denies Double-Crested Cormorant Depredation Permits On January 9th, Representative Rick Crawford introduced the Safeguard Aquaculture Farmers Act, a legislation that will provide the force of law to allow fish farms in 13 states (Alabama, Arkansas, Florida, Georgia, Kentucky, Louisiana, Minnesota, Mississippi, North Carolina, Oklahoma, South Carolina, Tennessee and Texas) to legally protect farm-raised fish from double-crested cormorants. Senator Tom Cotton will collaborate shortly with companion legislation in the Senate. The most effective means to get congressional attention is to inform your representatives and senators about the importance of this act for fish farmers, and ask them to sponsor the bill or to vote in its support. 2016 Aquaculture Webinar Series Now Available During 2016, the U.S. Aquaculture Society (USAS), North Central Regional Aquaculture Center (NCRAC) and National Aquaculture Association (NAA) produced a series of aquaculture webinars that featured 14 current and timely aquaculture topics, presented by knowledgeable experts. » 13

For more information about any of the above topics contact the NAA at:


Potential drivers

of virulence evolution in aquaculture David A. Kennedy,1,2 Gael Kurath,3 Ilana L. Brito,4 Maureen K. Purcell,3 Andrew F. Read,1,2 James R. Winton3 and Andrew R. Wargo5

Infectious diseases are economically detrimental to aquaculture, and with continued expansion and intensification the importance of managing infectious diseases will likely increase. In this paper, we use evolution of virulence theory, along with examples, to identify eight practices common in aquaculture that theory predicts may favor evolution toward higher pathogen virulence.

Introduction Emergence of highly virulent pathogens has devastated many food production industries. Examples include Irish potato culture in the mid-1800s and Taiwanese prawn culture in the 1980s. Given the rapid growth and dynamic nature of aquaculture worldwide, it seems likely that even without evolution, epidemiological changes will lead to increases in the disease burden of aquaculture. Strong evidence, nevertheless, suggests that pathogen evolution, including evolution of virulence, is also playing a role in the emergence of some diseases in aquaculture. Here, we consider how current management practices may make aquaculture vulnerable to the evolutionary emergence of high-virulence pathogen strains. We define “virulence� as the deleterious health effects of pathogen infection on a host. By studying how aquaculture practices alter pathogen ecology, insight can be gained into the likely direction of this evolution. To organize our discussion, we begin with practices related to intensive aquaculture operations that may have incidental impacts on the evolution of virulence. We then turn to aquaculture practices that are used specifically to control infectious disease in the short-term that may facilitate pathogen virulence evolution in the long-term. Practices related to intensive aquaculture operations

Rearing at high densities A large branch of evolution of virulence theory is based on an assumption that, while hosts are alive, pathogen strains with high virulence tend to have higher transmission rates than strains with low virulence. Nevertheless, high virulence strains tend to shorten infectious periods by killing their hosts more quickly, and so pathogen fitness may be evolutionarily optimal at intermediate virulence levels (Fig. 1). 14 Âť

persist. The consistently high rearing densities of aquaculture are thus novel environments for pathogens, and could facilitate evolution of increased pathogen virulence.

The fitness gain from increased infectiousness increases with the number of susceptible hosts, but the fitness cost of shortening the infection period does not. Thus, theory predicts that increases in host densities can lead to evolutionary increases in virulence. Even in the absence of a tradeoff between infectiousness and virulence, high host densities can allow for the maintenance of pathogens that would otherwise kill hosts too quickly to

Compression of rearing cycle Theory predicts that virulence levels depend on the natural lifespan of hosts, because virulence that results in shorter infectious periods is more costly in long-lived hosts than shortlived hosts. Shortening the effective host lifespan by compressing the rearing cycle may thus favor evolution of increased pathogen virulence. Pathogens that theory predicts are most likely to evolve higher virulence due to generational compression are those that can induce chronic, persistent infections with lifelong potential for pathogen transmission, such as the koi herpesvirus Cyprinid herpesvirus-3 in koi and carp, infectious pancreatic necrosis virus in salmonids and white spot syndrome virus in shrimp. Tremendous improvements Âť 15


to aquaculture growth rates can be achieved through selective breeding, and as growth rates increase optimal cycle lengths are likely to decrease, which may favor pathogen evolution toward increased virulence. Use of broodstock with limited host genetic diversity Pathogens that replicate quickly within their hosts, for example by evading detection by the immune system, are often assumed to be selectively favored, but high host genetic diversity is thought to reduce this advantage. When host populations have high genetic diversity, chains of pathogen transmission are likely to involve a diverse set of hosts, and so specialization on any single host genotype is unlikely. Pathogen strains that specialize on low diversity populations may have high virulence in those populations, and low virulence in more genetically diverse wild populations, because of tradeoffs between generalism and specialism. Accepting endemic disease in cultured populations When endemic disease is maintained in a host population, pathogens have opportunities to adapt to the specifics of that situation. As pathogens become better adapted to replication in a particular setting, virulence in that setting will often increase. Within aquaculture there are many diseases for which the cost of eradication is

prohibitively expensive or control options are unavailable. Pathogen exchange between wild and cultured populations reared in close proximity can also make eradication of disease economically infeasible.

Practices specific to control of infectious disease

Vaccination Vaccines that protect hosts from disease symptoms, but allow for some level of pathogen infection and onward transmission can lead to the evolution of increased virulence. This may result in a decline in vaccine efficacy and more severe disease in unvaccinated individuals for two reasons. First, for vaccines that prevent host death but do not prevent infection or transmission, the infectious periods of highly virulent strains tend to be extended because infected hosts live longer. Second, pathogen fitness in vaccinated hosts may be enhanced by traits that often correlate with virulence, such as immune suppression or rapid replication. Most aquaculture vaccine development is focused on preventing disease symptoms that slow host growth or induce mortality, as opposed to preventing infection and transmission. Many aquaculture vaccines are thus precisely those that are predicted to prompt the evolution of more virulent strains. Breeding for disease resistance When disease resistance exists with-

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out completely blocking the potential for infection and transmission, pathogen evolution can occur in disease resistant hosts. Theory predicts that evolution of pathogens in disease resistant hosts can lead to the evolution of increased virulence. Similar to the case of vaccination, the selective advantage of high virulence would likely be reduced if aquaculture breeding programs were focused on preventing pathogen infection as opposed to reducing disease. Chemotherapy – the use of antibiotics The use of antibiotic drugs might also select for the evolution of increased virulence if the mechanism that confers drug resistance is linked to virulence. The highly studied bacterial plasmid, IncI1, found in both human and animal pathogenic bacterial species contains virulence factors, adhesion proteins and type IV pili systems, and a gene for beta-lactamase resistance that simultaneously confers antibiotic resistance and high virulence. While several examples of antibiotic resistance have been reported in aquaculture systems, to our knowledge, linkages between virulence and antibiotic resistance have yet to be identified in an aquaculture setting. Reducing vertical transmission of pathogens Whether pathogens are transmitted vertically, meaning from parent to

offspring, or horizontally, meaning between conspecifics, is predicted to have important effects on the evolution of virulence. This is because new infections from a strictly vertically transmitted pathogen can only occur during host reproduction, and so a vertically transmitted pathogen that kills its host before reproduction could not persist, whereas an equally virulent horizontally transmitted pathogen may be able to. Thus, evolution of high virulence is unlikely for vertically transmitted pathogens. However, while vertical transmission has been reduced in many types of aquaculture, most aquaculture pathogens that are transmitted vertically are also transmitted horizontally under favorable conditions. By reducing vertical transmission, the relative importance of horizontal transmission increases. Theory predicts that this may lead to virulence increases.

Conclusions Mitigating infectious diseases is one of many challenges to aquaculture. We have identified several aquaculture practices that might drive evolution of virulence and thus alter future disease risk. Ultimately, more research is needed to make conclusive statements about virulence evolution in aquaculture diseases and its impacts on both wild and aquaculture populations. We have not discussed aquaculture practices that might drive evolution of pathogens toward decreased virulence. For example, culling strategies that selectively target diseased populations or individuals may favor low virulence pathogen strains over high virulence strains, thereby driving evolution toward reduced virulence. Such practices are not our focus here though, because they present no conflict between short-term and long-term costs. In general, economic considerations in aquaculture tend to favor managing for reduced impacts of disease today rather than considering avoidance of potentially increased cost in the future. As a result, among aquaculture professionals the potential risks associated with evolution of virulence due to farm practices are not yet widely recognized. Our hope is that this synthesis of theoretical predictions and observations from the practice of aquaculture may stimulate consideration of these ideas, future investigation, and where appropriate, development of potential mitigation strategies.

Center for Infectious Disease Dynamics, Departments of Biology and Entomology, The Pennsylvania State University, University Park, PA, USA 2 Fogarty International Center, National Institutes of Health, Bethesda, MD, USA 3 U.S. Geological Survey, Western Fisheries Research Center, Seattle, WA, USA 4 Massachusetts Institute of Technology, Cambridge, MA, USA 5 Virginia Institute of Marine Science, College of William and Mary, Gloucester Point, VA, USA 1

Kennedy, D., Kurath, G., Brito, I., Purcell, M., Read, A., Winton, J., Wargo, A. (2016) Potential drivers of virulence evolution in aquaculture. Evolutionary Applications. 9 (2016) 344–354. doi:10.1111/eva.12342

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We are Heliae You probably don’t know us. We understand. We are new to the field of aquaculture. But we are not new at all.


or nearly a decade Heliae has been a leader in the development of microalgae technology. We have leveraged that technology to develop products for applications ranging from human health to plant agriculture. Our customers and partners range from startups to some of the world’s largest companies.  Our research campus and state of the art production facility is located just outside of Phoenix, Arizona, USA, but we are globally focused. In 2016 we celebrated the opening of our first joint venture, Alvita, in Japan, and we regularly collaborate with individuals and companies from around the world. Quality is a critical component of what we do. Over 10 % of our workforce is primarily focused on quality control and quality affairs. All of our products are subjected to rigorous quality controls in our FDA FSMA/ GMP-compliant facilities. Our aim is to unlock the full potential of microalgae, bringing sustainable, natural products to market that improve peoples’ lives. To do this we have brought together a uniquely qualified team of engineers, biologists and chemists, who are focused on making discoveries and inventing new technologies in this still underdeveloped field.

So, why are we introducing our company to you? We’ve made a breakthrough. A breakthrough that offers the promise of 18 »

providing feed formulators with countless options for improving feeds using materials obtained from an infinitely-scalable source. We are nearing completion of our development of this remarkable new product and soon will shift to commercial launch. Through diligent effort, our research and development team has discovered, isolated, and cultured a robust strain of DHA-rich microalgae and our production engineers have developed a companion manufacturing technology that will allow Heliae to offer this innovative new product to the aquaculture market at disruptive prices. We have proven that we can produce at very large scale within a small manufacturing footprint. Our microalgae contain a high level of DHA and very little else. This very simple profile allows feed producers to precisely target DHA content in feed without impacting other formulation parameters. This permits formulators to make products optimized for the specific needs of various species, life-cycle stages, and desired nutritional content. Additionally, because it is naturally encapsulated, our DHA-rich microalgae provide

a stable vehicle for incorporating into feed products. Our overall value proposition is simple. Our new DHA-rich microalgae ingredient will provide formulators the ability to produce products having a precise, controlled DHA level, while our unique production technology will allow us to provide this product at a price that will make this powerful new tool broadly accessible. With decreasing levels of DHA in salmon and other important fish species, and ever greater pressure on fisheries, we believe the time is right to bring our DHA-rich microalgae product to the aquaculture market.

What do you think? Let us know by visiting us in Booth 322 at Aquaculture America 2017 in San Antonio, Texas. You can also learn more by contacting us at We look forward to telling you more about our company and our new DHA-rich microalgae, and we look forward to learning how our company and technology can help you reach your goals. We are Heliae. We hope to see you soon.

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was initiated by Charoen Pokphand Foods Public Co. Ltd. in Thailand (CPF) in late 2009.

Development of SPF base populations To establish a broad genetic base for a selective breeding program, eight founder populations were collected from various geographic locations in India, Myanmar, Vietnam and Thailand. The procedure of developing SPF based populations was adapted from Moss et al. (2003) and outlined in Figure 2. At initiation, adult prawns of each founder population were selected based on their size and health appearance, and held in individual containers in a designated quarantine station. Pleopod samples were taken from each prawn and checked for MrNV and Donghuo Jiang, Ph.D. XSV using reverse-transcription PCR (Yoganandhan et al., 2005). Males and females with negative PCR results were The giant freshwater prawn (GFP), Macrobrachium rosenbergii, used for mating under strict biosecurity is farmed on a relatively large scale in many countries. The major conditions. Nauplii were reared in individual tanks to PL10, when they were producers include China, India, Bangladesh, Thailand, Vietnam and tested again to verify their health status. Malaysia in Asia, and Brazil and Ecuador in South America. In 2009-2010, roughly 1,000 individual adult prawns were screened, yielding orld aquaculture pro- culture production of GFP in Thai- a total of 294 broodstock with negaduction of GFP reached land had been steadily increasing until tive PCR results from the two rounds a peak of 226,800 tons WTD first struck the industry in 2003. of screening. These broodstock were in 2007 (FAO, Fishstat The causative agents of WTD have then used to produce 159 full-sib and 2016) and the production level has been identified as two viruses, “Macro- half-sib families during 2010-2011. been fluctuating considerably since brachium rosenbergii nodavirus” (MrNV) Upon confirming their health status, then (Figure 1). Some reasons hinder- and its associated “extra small virus” the juveniles were transferred into a biing the growth in production in recent (XSV). The viruses not only cause a osecure nucleus breeding center (NBC) years include disease outbreaks, es- milky whitish appearance in larvae, as SPF base populations to initiate the pecially the white tail disease (WTD), post larvae (PL) and early juveniles, genetic selection program. Throughout the breeding program, which directly resulted in low numbers but also result in mass mortality in and poor quality of prawn post larvae prawn hatcheries and consequently routine health surveillance was imple(PL). There is also genetic deteriora- huge economic losses. The hosts of mented in the NBC, with monthly tion, possibly due to unintentional in- these viruses include marine shrimp, sampling of different stages of prawns breeding from improper broodstock Artemia and aquatic insects. Studies for PCR tests in the CPF Central Remanagement. The shift to farming the showed that WTD can be transmitted search Laboratory. In addition to Pacific white shrimp, Penaeus vannamei, either vertically from infected brooders MrNV and XSV, other known shrimp in low salinity or freshwater areas is an- to their offspring or horizontally in cul- viruses, such as the infectious hypodermal and haematopoietic necrosis other contributing factor. ture systems. In Thailand, the giant freshwater In order to systematically address virus (IHHNV), Taura syndrome viprawn is a favorite seafood species with the common issues of deteriorating rus (TSV), white spot syndrome virus both high market value and demand. genetics and high disease risks to the (WSSV), yellow head virus (YHV), It is the main ingredient for a famous prawn farming industry, a GFP genetic infectious myonecrosis virus (IMNV) Thai signature dish, Tom Yum Goong, improvement program based on the and monodon baculovirus (MBV) were the hot and sour prawn soup. Aqua- specific-pathogen-free (SPF) concept monitored periodically as well. New vi-

Selective Breeding

for SPF Giant Freshwater Prawn


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ruses discovered in recent years, such as covert mortality nodavirus (CMNV) and Macrobrachium rosenbergii Taihu virus (MrTV), were also added to the surveillance list in 2015. All stocks in NBC have remained free of these viral pathogens over the past five years.

Selective breeding program The breeding goals of the SPF prawn genetic improvement program were to improve mature body size, growth rate, survival, and to a lesser degree, density tolerance. A combined withinand between-family selection scheme was applied. Individual families were produced via designed pair mating. Hatched nauplii from the same family were reared in tanks to 3-5 g when juveniles were sexed. The 20 largest individuals of each sex were tagged from each family with visible implant elastomer (VIE) for familial identification. Communal tests of tagged prawns were carried out in recirculating concrete tanks, with ~20 families per batch. At the termination of the performance test, prawns were individually weighed and recorded by sex and number of claws (zero, one or two). Male prawns were further classified into four categories according to their morphological appearance, blue claw (BC), orange claw (OC), small (SM) and no claw (NC). Female prawns were classified into two categories, the egg-carrying females as berried (BF) and non-berried females (NF). All data were stored in a database and used for further analyses. Variance and covariance components were estimated using the restricted maximum likelihood method (REML). The estimated breeding values (EBV) of individuals were calculated for various traits, harvest weight (HWT, g), average daily gain (ADG, g/ day) and survival rate (SR%), using different statistical models. In all models, communal tanks and gender were always set as fixed effects; male morphotypes were not included because nearly all males were BC but with different numbers of claws. Other factors, such as age and initial stocking weight (IWT,

g), were used as covariates for exploring estimations using various models. Families were ranked and selected within each batch, based on the selection index. Within each family, best males and females were visually selected for breeding based on their body size, morphotype, reproductive status and physical appearance. Currently, the selective breeding program is in its 5th generation (see Table 1). In the F1 generation, only within-family selection was conducted with no communal testing. The percentage of families selected in each generation decreased from nearly 60 % in the 2nd generation to 40 % in

the 5th generation, corresponding to an increase of selection intensity (i) from 0.644 to 0.966 for the betweenfamily selection, as routine operations became more consistent. On average, the top 20 % of males and 30 % of females were kept from the selected families as breeding candidates to produce the next generation. Genetic analyses showed consistent gains have been made for HWT and ADG (Figure 3), while improvement for SR% was not significant. Across five generations, the h2 estimate obtained from the animal model was 0.4066 for harvest body weight, which was likely over-estimated because the testing design did not allow the distinction between common environmental effects and maternal effects. The cumulative genetic gains were estimated to be 38 % in five generations. Although a lower selection intensity occurred in G1, an average of 7.6 % genetic gain for ADG per generation was achieved.


Prawn harvesting.

NBC Nursery tanks.

Numerous growth trials have been conducted to evaluate production performance of the genetically-improved SPF strain under commercial prawn farming conditions in Thailand. In growout ponds initially stocked with 1-2 g small juveniles at a density of ~15 pcs/m2, average weight of males and females can reach to 40 g and 35 g, respectively, within 90 days (Figure 4). The survival rates are at 80-85 %. Currently, the SPF prawn strain is being introduced to China and Myanmar for commercial farming. Currently commercial prawn farming is moving toward two extreme modes of production, tailored for different target consumption markets. One is to achieve the large mature body size at low density (i.e. in Thailand) and the other is to reach small marketable size as fast as possible at very high density (i.e. in China). Given the complex social hierarchy and strong competition in GFP populations, different breeding strategies are warranted to meet the demands of such two markets. The selection scheme implemented was primarily based on the direct genetic effect of individual performance. Social genetic effects must be properly estimated to increase the accuracy of selection and avoid the undesired consequence of increased competition. To the best of my knowledge, this is the first GFP selective breeding program in the world that was based on SPF populations and has maintained SPF status consistently for 5 years. In summary, a cumulative 38 % in genetic gain for five generations has been achieved through a combined between-family and within-family selection scheme. More initiatives are still needed to increase the accuracy of selection, to avoid unintended consequences of increased competition, and to generate greater yield and profitability for the prawn farming industry. Donghuo Jiang holds B.S. and M.S. degrees from the Ocean University of China, a Ph.D. from Texas A&M University, and an Executive MBA from the Sasin Graduate Institute of Business Administration of Chulalongkorn University. He is currently a Vice President at Charoen Pokphand Foods in Bangkok, Thailand.

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Eastern Little Tuna, Euthynnus affinis, (Cantor, 1849):

Reproductive Maturation within One Year of Rearing in Land-based Tanks

Eastern little tuna (ELT, Euthynnus affinis) has proven to have great potential for aquaculture due to its rapid growth and high commercial value. This study describes the successful closing of the complete life cycle of ELT in land-based tanks.

Yutaka Takeuchi et al., 2016


lobal demand for tuna has increased significantly in recent years, which has led to an increase in capture production that affects the wild population. The eastern little tuna (ELT, Euthynnus affinis) is a commercially important species, widely distributed in the Indo-Pacific region. ELT has recently drawn researchers’ attention, since it has great poten24 »

tial for aquaculture due to its rapid growth and increasing demand in the market.

Current Situation Nowadays, in Japan, wild-caught juveniles are used as seed for ELT farming. However, ELT’s large-scale farming has not been achieved because there are no large schools of this species in the area, and ELT seeds are usually

obtained as bycatch from fishing operations targeting other species. The majority of Japanese fish farming operations are small businesses focused on red sea bream (Pagrus major) and yellowtail (Seriola quinqueradiata) culture. The commercial size and weight of ELT (45 cm and 1.5 kg) makes it a suitable species to rear in conjunction with these species in small net pen facilities. As ELT

ELT is a tropical or sub-tropical tuna species and is naturally distributed in warm waters (18-29ºC). Optimum water temperature for ELT maturation and spawning is between 24-28ºC. This suggests that the maintenance of suitable water temperature is essential for stable maturation. So far, ELT aquaculture land-based facilities are more appropriate than net per farming operations, as they allow the maintenance of stable water temperature. In the following paragraphs we review how we achieved completion of the ELT life cycle and the viability of a stable production of a F2 generations. has a similar taste to that of the Pacific bluefin tuna (PBT, Thunnus orientalis) and the market price is higher than that of both red sea bream and yellow tail, ELT has a great potential as a substitute for other aquaculture species used in Japan. ELT’s flesh rots quite quickly if not treated properly once it’s harvested. Therefore, aquaculture is a viable alternative for its commercialization, since it allows the fast processing and preservation of the product once it is harvested.

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Facilities and ELT Broodstock Management The experiment was carried out at Tateyama Station (Banda), Field Science Center of the Tokyo University of Marine Science and Technology in Japan. Seed production of first generation (F1) derived from wild-caught ELT broodstock was conducted in 2010, 2011 and 2012. Artificial ELT seed production ELT used as broodstock were raised for one year. Fertilized eggs used for seed production in 2010, 2011 and 2012 were obtained through induced spawning, through the administration of Gonadotropin-releasing hormone analogue (GnRHa), in cholesterol pellets. GnRHa was implanted into the dorsal muscles of specimens at doses of 100 μg kg-1 BW.


Reproduction of F1 ELT Reared in Land-based Tanks Results from sex identification achieved through sex steroid assays showed that sex ratios were not significantly biased in any year class (male: female, 4:5, 6:9 and 3:5 in 2010, 2011 and 2012, respectively). In each year class, spawning was successfully induced by the administration of GnRHa, and water temperature during spawning periods was maintained between 23.7-27.8ºC. The spawning induced in F1 ELT during each trial yielded an F2 generation that grew and developed in similar conditions as for F1’s.

Fertilized eggs were collected and introduced into cylindrical 100 L rearing tanks. It was necessary to reduce larvae density, in order to avoid the high mortality rates related to high rearing densities during early development. It was determined that larvae were strong enough to survive the experiment protocols, which included tank transfer, at 9-10 dph and 350, 2500 and 240 larvae were selected for their use in seed production at 9-10 dph in 2010, 2011 and 2012, respectively. Diet series for ELT seed production are summarized in Figure 1. As they grew, the F1 ELT were transferred to appropriately sized tanks (1, 5, 9, 38 and 50 m3). In order to improve their survival and growth, water temperature was maintained at >18ºC, until fish reached 1 year of age. When fish died during the rearing period, their total length (TL), body weight (BW) and gonadal weight (GSI) were measured. 26 »

Spawning Induction in F1 ELT Broodstock Through the ELT spawning season (August-October), water was maintained at >25ºC. In order to determine the sex ratio of reared ELT, which could not be accomplished by external morphological characteristics alone, sex identification was performed using sex steroid assays. Results Land-based Tank Culturing of F1 ELT The growth, length and survival of the F1 ELT hatchlings in the 2010, 2011 and 2012-year classes and the water temperatures used in the associated rearing tanks are shown in Figure 2. The development and growth of F1 ELT, until maturity, are shown in Figure 3. Transformation to juveniles occurred at around 12-20 dph (Fig. 4b), which suggests that ELT exhibited rapid growth both as juveniles and young fish.

Discussion The F1 generation of ELT wildcaught broodstock showed normal development and growth under inland rearing conditions, and it was confirmed that the administration of GnRHa induced spawning in 1-yearold F1 ELT in each year class. In natural conditions, ELT reach reproductive maturity at 2 years of age with a minimum size of 45-50 cm TL. In this study, F1 ELT reared in land-based tanks were able to reproduce at 1 year of age and 40 cm TL. This was possible thanks to optimal rearing conditions (water temperature and feeding) for precocious puberty. In the present experiment, an F3 generation of ELT was obtained through 3 years of full-cycle culturing; which suggests that the rearing techniques for ELT using landbased tanks established in this study could allow for a stable acceleration of generation time. Further research is needed in order to establish if F3 generations of ELT exhibit improved performance when compared with F1 generations. A common obstacle in Scombridae culture is piscivorous behavior, which occurs in the very early stages of development. In this study, although continuous hatched larvae production was achieved, survival rates (Fig. 2d) during early development stages

der to increase survival and reduce the incidences of physical abnormalities.

were low. This is attributed to the piscivorous behaviors in ELT (aggressive behaviors and cannibalism). It has been previously reported that this kind of behavior can be suppressed by supplying excess amount of fish larvae, as done in this study. However, the aggressive behaviors remained significant. In PBT seed production, collision with the tank walls is a known cause of mortality in juveniles. In the present study a similar situation was observed, which not only lead to mortalities, but also to physical abnormalities in surviving fish. These physical abnormalities affected nor-

Potential seed production for mariculture facilities Wild-caught ELT have shown a tolerance for low water temperatures (min. 15ºC) as long as they are at least 30 cm in TL. The production of ELT mal development and consequently seed outside of the spawning season had a negative impact on spawning in in land-based tanks has a great potenadult fish. tial for Japanese aquaculture, since it Evidence of this is the improve- allows ELT juveniles to reach a suitment in the hatching rate observed in able size (30 cm) prior to low-temperthe 2012-year class compared to 2010 ature periods and then continue the and 2011, which is the result of an in- culture process in farming operations crease in the number of healthy ma- using net pens. ture fish that did not show any abnormalities. In the 2010 and 2011-year Ryosuke Yazawa , Yutaka Takeuchi , Kenta Satoh , Yuri Machida , Kotaro Amezawa , Naoki Kabeya , Yukinori classes, unlike 2012, individuals were Shimada1 & Goro Yoshizaki reared in several smaller tanks beDepartment of Marine Biosciences, Tokyo University of Marine Science and Technology, Tokyo, Japan fore being transferred to larger tanks, Research Center for Advanced Science and Technolwhile ELT seeds produced in 2012 ogy, Tokyo University of Marine Science and Technology, Tateyama, Japan were transferred directly to a larger tank. Further research is needed to Eastern little tuna, Euthynnus affinis (Cantor, 1849) mature and reproduce within 1 year of rearing in land-based improve the rearing techniques in ortanks. Aquaculture Research, 2016, 47, 3800–3810 1









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Performance of Litopenaeus vannamei postlarvae Reared in Indoor Nursery Tanks Under Biofloc Conditions at Different Salinities and Zero Water-Exchange Héctor M. Esparza-Leal, João A. Amaral Xavier and Wilson Wasielsky Jr.

Nurseries help to reduce health risk in shrimp farming, while biofloc technology has proven to maintain water quality and to contribute to shrimp nutrition. In this study, the combined effects of different salinities and biofloc conditions were evaluated in L. vannamei postlarvae culture.


ver the past decades, shrimp has become an important seafood product due to its increasing demand and the maintenance of its price in the market. This has led diverse countries in Latin America and Asia to venture in shrimp farming, even though they don’t have the optimal conditions for its culture. Among all shrimp species, Litopenaeus vannamei is known for its high tolerance to different salinity levels, making it an attractive aquaculture species for the industry. Nowadays, disease outbreaks remain a limiting factor for aquaculture industry development. This is the result not only of the mere presence of pathogens; culture management and suboptimal environmental conditions also impact aquaculture farms. Therefore, disease prevention and control should consider diverse 28 »

factors, such as biosafety measures, adequate nutrition and enhancing the immunity of the cultured species, among others. Nursery systems, which are a transitional stage between the hatchery and grow-out ponds, have proved to successfully reduce health risks in shrimp farming. As shrimp farming in low salinity is a trend that will continue to grow globally, the performance of L. vannamei postlarvae in the nursery at different salinities with a Biofloc Technology (BFT) system needs to be explored further.

Biofloc Technology Biofloc Technology (BFT) is one of the most attractive alternatives for improving biosecurity and increasing sustainability in shrimp farming. BFT has proved to maintain good water quality in aquaculture systems and to contribute to nutrition.

The basic principle of BFT systems is to recycle waste nutrients, which deteriorate the water quality, through microorganisms present in the aquatic environment. Heterotrophic microorganisms are stimulated to grow by controlling the C/N ratio in water through the modification of the Ccontent by adding an external carbon source. This allows bacteria to assimilate the ammonia waste. In addition, BFT has proven to enhance growth and survival, as well as enhancing the shrimp innate immune system and providing improved protection against opportunistic pathogens. The impact of salinity on L. vannamei performance (growth, survival, molting frequency, oxygen consumption and immune response) has been studied in the past. However, the optimal salinity for L. vannamei growth is still controversial, and the combined effect of salinity and BFT in white shrimp postlarvae (PL) has rarely been studied.

The experiment The effect of seven salinity levels (2, 4, 8, 12, 16, 25 and 35 %0) on the performance of L. vannamei postlarvae reared within a BFT system with zero

aeration and a supply of molasses to maintain C/N ratio at approximately 12:1 to produce a dominant heterotrophic community.

Parameters measured During the 28 days of the experiment, biometrics were performed daily and at the end of the experiment growth parameters were calculated (Table 1). During the experimental period, the photoperiod was natural and the water temperature was maintained with one heater immersed in each tank. Throughout the experiment, DO (mg/l), temperature (ºC), pH, and salinity (%0) were measured twice a day. On a weekly basis, total ammonia-N, nitrite-N, nitrate-N (mg/l), phosphate-P (mg/l), total suspended solids (TSS, mg/l) and alkalinity (mg CaCO3/l) were measured. water-exchange was evaluated in tripliSalinity refers to the total concate. Additionally, this study evaluated centration of all ions in the water; water quality in all salinity treatments. therefore, a major ions analysis was The experiment was carried out performed. At 0, 14 and 28 days of at the Marine Aquaculture Station culture, surface water samples were (EMA) of the Federal University of collected from each tank for a major Rio Grande, Brazil. L. vannamei nauplii ions analysis: calcium Ca2+, magnewere acquired from a local laboratory sium Mg2+, Potassium K+, SO42- and and kept in the shrimp hatchery until Sodium Na2+. they reached the post-larval stage (PL ’15). A batch of 1,800 post-larvae was Water quality parameters separated into seven tanks, adjusting The DO, temperature and pH were the salinities by approximately 3-6 %0 not significantly different among daily until final salinity levels of 2, 4, treatments. Means of DO= 6.1 ± 0.2 8, 12, 16, 25 and 35 %0. Later, shrimp mg/l, temperature= 30.7 ± 0.2 ºC, were stocked in experimental tanks at and pH= 8.0 ± 0.0 were maintained. each salinity treatment, with 80 organ- However, there were significant difisms per tank (average body weight ferences among treatments for other 0.016±0.002; ≈PL ’24). During the 28 parameters, as shown in Figure 1. In days of the experiment, shrimp were this study, the nitrite-N concentration fed with commercially formulated in the salinities of 2, 4, 8, and 12 %0 feed (40 % protein, 8 % lipid) twice exceeded the safe range for L. vandaily, adjusting the feeding rate daily. namei juveniles. The recorded nitrite-N concentration may be one of the Biofloc preparation main factors that caused up to 100 % Eight days before the experiment shrimp mortality in 2 and 4 %0 treatbegan, the biofloc was prepared. For ments, and 27.1 % and 20 % in the this, tanks with each salinity treat- 8 and 12 %0 treatments, respectively. ment level were supplied with 25 % In 2 and 4 %0 treatments, nitrite-N of total volume with water from a concentration peaks were associated grow-out tank that exhibited a ma- with the mortality records. ture biofloc. During this time, each All treatments showed a trend of tank was maintained with constant increasing nitrate-N concentration as » 29


the TSS concentrations were higher in treatments with higher salinities, which agrees with previous reports about a trend towards increasing suspended particle aggregation and floc size with an increase in salinity. In this study, this was only evident in the 25 %0 treatment.

the rearing cycle progressed, suggesting a greater intensity of the nitrification process. In most of the study, the highest nitrate-N concentrations were registered at the highest salinities. At the beginning of the study, the treatments with lower salinity (2, 4 and 8 %0) registered alkalinity values lower than 50 mg/l, while the treatments with higher salinity registered values >100 mg/l. In order to maintain ac-

Experimental design.

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ceptable alkalinity values for shrimp culture (>100 mg CaCO3), all treatments were supplied with sodium bicarbonate. From the beginning of the trial, the TSS concentration in all treatments exceeded the recommended limits (500 mg/l) for good shrimp performance. Aiming to reduce the TSS concentration, all tanks were clarified. During the entire study,

Ionic composition effects on shrimp growth In the past, it has been reported that the ionic composition of water may be a more important limiting factor for shrimp growth and survival than the salinity itself. The deficiencies in certain ions (sodium, calcium, magnesium and potassium) have a negative impact on the growth and survival of cultured species. In this study, only the calcium registered a decreasing concentration among sampling periods. The impact of low concentrations of calcium, magnesium, and potassium that prevailed at lower salinities were more evident on the shrimp growth. In addition, it has been reported that the low growth of shrimp reared at low salinities may be caused by the fact that the dietary protein is used not only as a source of amino acids for weight gain, but also for maintenance of the osmotic pressure. The lack of significant differences among some treatments could be related to the fact that shrimp were reared in biofloc systems, environments of high natural productivity with many nutritional benefits.

Productive parameters of shrimp postlarvae Apart of 2 and 4 %0 treatments, which registered 100 % mortality in the first two weeks, the rest of the treatments (8, 12, 16, 25 and 35 %0) registered a shrimp survival of >72 %. Shrimp survival was affected by salinity, especially when it decreased from 35-25-16 to 12 and 8 %0. The organisms reared at low salinities presented lower final weights and specific growth rate than those reared at higher salinities (Table 1 and Figure 2).

At a salinity of 25 %0, shrimp maintained their isosmotic point and registered the lowest FCR. For the rest of the treatments, a direct relationship between FCR and salinity wasn’t detected.

Conclusion In conclusion, it is essential to determine the optimum salinity level in nursery under biofloc conditions for not affecting shrimp performance. In this study, salinity affected some water quality parameters; however, only

the combination of a high nitrite-N concentration (>4 mg/l) and low salinity (2 and 4 %0) caused up to 100 % shrimp mortality in the first 2 weeks. Survival was affected by salinity in 8 and 12 %0 treatments, although high shrimp survival (>72 %) was registered in all treatments. Salinity also affected the growth of shrimp post-larvae. Organisms reared at low salinities registered a lower final weight and SGR compared with the higher salinity treatments. During the study, an inverse relationship between ion concentration and final weight of the shrimp was demonstrated. And, apart from calcium, all major ions were not significantly altered among treatments. Hector M. Esparza-Leal, Departamento de Acuacultura, Instituto Politécnico Nacional-CIIDIR Unidar Sinaloa, México and Laboratório de Carcinocultura, Instituto de Oceanografia, Post-doc, Universidade Federal do Rio Grande (FURG), Brazil. J. Amaral Xavier and W. Wasielsky, Jr., Laboratório de Carcinocultura, Instituto de Oceanografia, Post-doc, Universidade Federal do Rio Grande (FURG), Brazil. Performance of Litopenaeus vannamei postlarvae reared in indoor nursery tanks under biofloc conditions at different salinities and zero water-exchange. Aquaculture International (2016) 24:1435–144

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Global Blue Technologies Approaching an Aquaculture Industry Differently Global Blue Technologies (GBT) is a super intensive shrimp farm that is hoping to transform aquaculture as we know it. Located in Taft, Texas, this innovative zero-discharge project has been able to consistently produce shrimp of colossal size since 2015, in a way that is both socially and environmentally responsible.


duardo Figueras, recently named CEO of GBT’s Taft Campus, welcomed us to this state-of-the-art site, where aquaculture has been re-defined. With more than three decades of experience, Figueras has been involved in the project since its early stages, and he has been responsible for the development of GBT’s genetic lines.

Who is Behind GBT? The persevering force behind GBT is David Wills. Before venturing into aquaculture, Wills spent a lifetime protecting and fighting for animal rights. It was at that time, and years later during his time as a consultant for Darden Restaurants, that Wills detected a problem behind shrimp farming: it represented a strong source of employment and income in developing countries, however, the traditional aquaculture techniques that were used had immense environmental impacts on ecosystems. In 1998, David collaborated in a university shrimp farming research project at Gulfport, Mississippi. Dur32 »

ing this period, he realized that the discoveries made were impressive but far from commercially viable. Afterwards, Wills and some colleagues founded Penaeus Ltd. to test different ideas on how to improve shrimp farming in an environmentally compatible way. An opportunity to take the project to a commercial scale emerged, and, in 2006, Wills opened a facility in Port Elizabeth, South Africa. The performance results were good, then Wills returned to the US where he started a small pilot aquaculture project in Brownsville´s Port Isabel, Texas. It was then that GBT´s innovative technology attracted investors’ attention, and the group started working on what is now known as Global Blue Technologies (GBT). The Vision Behind GBT GBT’s investor group is driven by a shared vision, presented by John Elkington in his book Cannibals with forks (1997). In this book, Elkington analyzes how companies implement sustainability principles in their business, and he presents the Triple Bottom

Line (TBL) principle: People, Planet, and Profit. The TBL may seem similar to the three aspects of sustainability (environmental, social and economic); nevertheless, Elkington gives special importance to transparency and the investors’ role in business, two key aspects for achieving sustainability. Besides generating profits, GBT’s investors are interested in giving something back to the environment. They really believe in the TBL principle, and all stakeholders have developed the entire project around it. Eduardo Figueras stated that GBT’s mission is to generate animal protein with low impact on the environment, while the project generates returns for investors and employees. Facilities Located on Copano Bay, Texas, GBT Taft Campus is composed of 4 production modules, housing 32 ponds. Each pond is approximately 1,600 m2. The inflated and imposing white domes that mark the site are one of the aspects that distinguish GBT. The domes have the function of protecting the ponds from viral diseases and climate events, and maintaining optimal conditions (temperature and humidity) for shrimp culture. The domes allow year-round production, with consecutive cycles of 140 days each. The ponds are stocked with PL 12 larvae from GBT’s own genetic core, at a stocking density of 150 PL/m2. GBT has achieved an average survival rate of 68 % and a Feed Conversion Ratio of 1.87. GBT staff has managed to harvest shrimp with an average size of 39 g. This can be attributed to the highly monitored recirculating aquaculture system andthe administration of 40 % protein and 25 % energy feed, among many other factors. At present, the production cost is $4.25 USD, a significantly higher cost than that of the main producing countries. However, GBT has achieved a selling price of $10.45 USD (head off), leaving a good profit margin. GBT offers a high value product and

The image allows to appreciate the imposing size of the domes and the larval breeding tanks.

there is a market that is willing to pay for it. Global Blue Technologies has developed its own brand - Copano Blues Shrimp®. So far, it has had excellent acceptance in the U.S. and other countries such as Japan. Japan is a peculiar and demanding market. Copano Blues Shrimp® has been considered as sushi grade – an unofficial term used by stores/ restaurants to refer to the highest quality of seafood offered in the market. Additionally, the company is planning the construction of a second production site in Texas to

satisfy the increasing demand of the region.

GBT Recirculating Aquaculture System The Recirculating Aquaculture System (RAS) used at GBT is a modular biosecure system that requires no chemical or antibiotic additives; it uses bacterial flocks, which allow for reduced feed costs and accelerated growth. In addition, water heaters are used to maintain temperature. All the water that enters the system is treated and recirculated. The massive multi-chambered biofilter

Eduardo Figueras, CEO of GTB next to a growthout pond housed inside of one of the domes.

that serves the 32 ponds is located in two adjacent buildings. After completing the construction of the first production module, the GBT staff had to master several challenges, like the system’s automation. “Over time, we have discovered that the domes are wonderful, but they also have certain complications that make automation harder. For example, changes in temperature during winter and the high humidity levels inside make it difficult to have electrical equipment indoors. We have adapted the design to our conditions. Each dome is different and better than the previous one,” shared Figueras. An aeration system, which is activated through an oxygen probe, was installed recently. However, feeding automation has not yet been achieved; it continues to be accomplished using feeding trays.

Sea Product Development (SPD) Seed production is essential for achieving more productive, efficient, biosecure and environmentally friendly aquaculture. Therefore, GBT has also developed its own genetic line of specific pathogen-free (SPF) Litopenaeus vannamei. Sea Product Development (SPD) is GBT’s genetics development center » 33


GBT’s Research and Development Area is working on the development of breeding and culture techniques for finfish species, especially black sablefish (Anoplopoma fimbria).

and core hatchery. SPD facilities are housed within air domes like GBT´s growout facilities, which, together with management protocols and strict control of all environmental parameters, produce ideal biosecurity conditions. SPD facilities have the capability of producing over 300,000 broodstock, 200 million postlarvae (PL) and 300 million nauplii annually. The genetic program is designed to produce two distinct lines, one for growth and the other for stress resistance to high-density stocking, every three months. Each family produced is challenged in laboratory and field conditions. The best performing families are selected and become the next generation of pure lines, which are never used in commercial ponds.

The combination of these two genetic lines generates crossbred animals that integrate the best growth and resistance characteristics. These hybrids become SPD broodstock. SPD is one of only two companies in the world that has genetic lines that are 100 % free of all the viruses listed by the WOAH. And in order to maintain this, the University of Arizona Aquaculture and Pathology Laboratory monitors SPD’s broodstock for diseases on a monthly basis. The USDA also certifies SDP’s larvae quality for export to Europe. In mid2015, the company won approval for selling broodstock to India, a country known for its strict restrictions on broodstock importation and commercialization.

SPD: Towards Shrimp Genetics’ Future Many crustacean species exhibit a bimodal growth pattern, where females grow larger than males or vice versa. In Litopenaeus vannamei, it has been demonstrated that females grow larger than males, up to 25 % and with lower FCR. Therefore, the production of an all-female population is desirable. Currently, SPD is seeking to partner with a company in Israel that has successfully developed the technology to produce all-female progeny in Macrobrachium rosenbergii. SPD is looking to develop this technology for L. vannamei. “In SPD, we want to differentiate ourselves, do what no one else is doing,” shared Figueras. “The path is already there, we just have to adapt the technology to L. vannamei. We expect to achieve this in the next 1-2 years. What are the benefits? Well, first, culturing only females allows a reduction in the disparity of sizes. Here is an example: when a female reaches 28-30g, a male barely reaches 22g. Nowadays, there are many genetic programs for aquaculture species, but the majority of the producers are unaware of the work that has been done,” commented Figueras. “The future in shrimp farming is not on what we are doing now. The future lies on what we are going to do in the next 2-3 years. We can’t stay behind with what is working today. We have to compete with ourselves to become better. We have to think about what hasn’t been made, break the barriers a little in order to make something distinct.” The Way Ahead for SPD Currently, GBT is working on building a second genetic development center in Yonaguni Island, the westernmost island of Japan. The process has been long, due to the strict planning and permitting requirements, but construction is expected to start at the end of 2017. The SPD site in Japan is intended to supply the increasing demand

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of Asian countries for high quality broodstock, estimated at nearly 300 thousand per year.

Current Situation GBT’s primary mission is to contribute to the environmentally and socially responsible production of marine animal protein. Since its conception, GBT has experienced rapid growth; therefore, for the time being, efforts will be focused on improving processes and generating profits for future investments. For GBT, production growth will be regulated by the capacity to maintain a low environmental impact and socially responsible production. “This year we are in

an adjustment process. Currently, we produce 7 kg/m2, and our goal is to reach 15 kg/m2. But for now, we will focus on achieving a steady production,” added Figueras.

Future Directions In addition to L. vannamei superintensive production, GBT is seeking to diversify production species. GBT’s research team is developing breeding and culture techniques for finfish species, especially black sable fish (Anoplopoma fimbria). The completion of this project is expected in the upcoming months. On the other hand, GBT Systems permits its replication anywhere in

the world. The investor group has certain preferences for investing in countries that are recovering from difficult situations, so do not be surprised if in the future you hear about the construction of a GBT Campus in Malaysia or Vietnam. Currently, GBT has another new project in sight: chitin extraction. Chitin is a by-product of the aquaculture industry, and it is a major component of shrimp shells. It has unlimited uses and is in high demand, especially in the pharmaceutical and cosmetic industries. At present, chitin plants are forbidden in North America and Europe, due to hazardous processes and high environmental impacts. This new venture is focused on funding an environmentally benign chitin production facility, which will benefit from the constant supply of GBT’s shrimp shells. So expect more from Global Blue Technologies in the coming years. It has demonstrated a commitment to the development of sustainable technologies to overcome some of the present-day and future industry challenges. More information can be found at » 35

R&D Centers

An Overview of Oceanic Institute of Hawaii Pacific University Shaun M. Moss, Ph.D.

For more than 50 years, the Oceanic Institute has been a world leader in the advancement of sustainable aquaculture technologies and contributed to a range of solutions to overcome current and emerging industry challenges.

Oceanic Institute of Hawai`i Pacific University covering 23 hectares in Waimanalo, Hawaii with the Ko’olau Mountains in the background. Sea Life Park, a public exhibit featuring local marine life, is located on the left side of the photo. (OI photo credit)


n 1962, a public auction was held for the lease of undeveloped coastal land in east Oahu, Hawaii for the purpose of constructing and operating an ocean science research facility and for a public exhibit featuring local marine life. The lease was issued to Pacific Foundation for Marine Research, a non-profit corporation dedicated to the advancement of research in all fields of marine sciences. Over time and after several name changes, the 36 »

Pacific Foundation for Marine Research eventually became the Oceanic Institute which has since focused its research efforts on applied aquaculture. In 2014, the Oceanic Institute merged with Hawaii Pacific University, the largest private university in Hawaii, to become the University’s first directed research unit. Today, Oceanic Institute of Hawaii Pacific University (OI) is a nonprofit research and development organization dedicated to aquaculture,

biotechnology, and coastal resource management. OI’s mission is to develop and transfer environmentally responsible technologies to increase aquatic food production while promoting the sustainable use of ocean resources. OI works with community, industry, government and academic partners, and non-governmental organizations to benefit local, national, regional, and international stakeholders in areas of aquaculture, food security, and marine conservation. OI is located on 23 hectares in Waimanalo, Hawaii and has over 10,000 m2 of roofed laboratory and office space, numerous tanks ranging from 1.5- to 30-ton capacity, outdoor ponds, and additional training and educational facilities. OI employs a team of 45 scientists, professionals, and support staff to conduct applied research which is integrated across four departments. In addition, faculty members, graduate students, and undergraduate interns from Hawaii Pacific University are actively involved in research at OI. OI’s four departments include: Finfish Department, Shrimp Department, Aquatic Feeds and Nutrition Department and Training and Education Department.

Finfish Department OI scientists working in this department develop aquaculture technologies to promote aquatic food production and help protect Hawaii’s coral reefs. Recent achievements in the area of marine conservation include the first-ever successful cultivation of captive-bred yellow tang (Zebrasoma flavescens), a valuable coral reef fish in high demand for the aquarium trade. Off the Kona coast in Hawaii, more than 280,000 yellow tang are collected annually from the coral reefs and OI’s achievement in producing captive-reared fish provides aquarium hobbyists with an alternative to wild-caught fish. OI scientists also have developed culture techniques for the collector urchin (Tripneustes gratilla), a native sea urchin which can effectively graze invasive macroalgae

Oceanic Institute of Hawai`i Pacific University covering 23 hectares in Waimanalo, Hawaii with Makai Pier in the background. Sea Life Park, a public exhibit featuring local marine life, is located in the foreground.

which are threatening Hawaii’s coral reefs. In addition, OI scientists have developed captive-rearing techniques for native Hawaiian food fishes, including striped mullet (Mugil cephalus) and milkfish, (Chanos chanos), to help revitalize ancient Hawaiian fishponds which represent the oldest and most culturally significant form of aquaculture in the U.S. Recently, OI provided more than 100,000 mullet fingerlings to several Hawaiian fishponds on the islands of Oahu and Molokai in an effort to help promote local food self-sufficiency. OI scientists also have developed maturation, hatchery, nursery, and growout techniques for other tropical and subtropical fish species including Pacific threadfin (Polydactylus sexfilis), mahimahi (Coryphaena hippurus), short-finned amberjack (Seriola riviolina), bluefin trevally (Caranx melampygus), and red snapper (Lutjanus campenchanus), as well as coral reef fishes such as flame angelfish (Centropyge loriculus), clownfish (Amphiprion spp.), and dottybacks (Pseudochromis spp.). Currently, OI scientists are working with research partners in the Republic of Palau to culture coral grouper (Plectropomus leopardus) and Saipan

(part of the Commonwealth of the Northern Mariana Islands) to culture fork tail rabbitfish (Siganus argenteus). Successful culture of these two species depends on the transfer of intensive copepod production technologies developed at OI.

Shrimp Department OI’s Shrimp Department has an international reputation for research on the selective breeding of Pacific white shrimp (Litopenaeus vannamei). In 1990, OI partnered with the University of Arizona to develop the world’s first captive population of specific pathogen free (SPF) L. vannamei, and OI was the first organization in the world to develop a family based breeding program for this species. As a member of the U.S. Marine Shrimp Farming Program, which was funded by the U.S. Department of Agriculture from 1985- 2011, OI transferred SPF selectively bred shrimp to the private sector in an effort to promote a shrimp broodstock industry in Hawaii. Hawaii is now home to several commercial SPF broodstock suppliers which generated an estimated $26 million in export revenue in 2015. The commercial availability » 37

of SPF, selectively bred L. vannamei broodstock catalyzed a major shift in Asia where shrimp farmers traditionally grew black tiger prawn (Penaeus monodon). According to the Food and Agriculture Organization of the United Nations, production of farmed L. vannamei in Asia increased 2,045 % from 2000 to 2013, whereas production of farmed P. monodon increased only 28 % during the same time period. This massive shift to L. vannamei farming in Asia can be attributed, in large part, to the work at OI. Currently, OI participates in several shrimp breeding projects in Asia, including a partnership with the Rajiv Gandhi Centre for Aquaculture, the research arm of the Marine Products Export Development Authority (MPEDA) for the Government of India. In addition to shrimp breeding, OI scientists have developed an indoor, recirculating aquaculture system to raise shrimp at super-intensive

R&D Centers

Captive-bred yellow tang (Zebrasoma flavescens). OI scientists have been studying this coral reef fish since 1999 and recently produced the world’s first juveniles for display in public aquaria and for marine aquarium hobbyists.

densities and with a very small environmental footprint. This system protects shrimp from outside pathogens and minimizes environmental impacts caused by effluent discharge because water in the system is recirculated. This technology is being commercialized by OI with partners in Asia and likely represents the future of global shrimp farming. OI scientists have also developed breeding and culture techniques for a variety of other tropical and subtropical marine invertebrates including the fleshy prawn (Fenneropenaeus chinensis), harlequin shrimp (Hymenocera picta), and the benthic polychaete Marphysa sanguinea. This latter species represents a potentially valuable food resource for the maturation of penaeid shrimp broodstock.

Dr. Chad Callan, Director of OI’s Finfish Department, inspects larval fish in OI’s hatchery. OI scientists recently produced the world’s first juvenile yellow tang (Zebrasoma flavescens), millet seed butterfly fish (Chaetodon miliaris), Potter’s angelfish (Centropyge potteri), and Hawaiian cleaner wrasse (Labroides phthirophagus) in captivity.

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Aquatic Feeds and Nutrition Department OI scientists working in this department conduct innovative research on feeds and nutrition for the global aquaculture industry. OI scientists have developed formulated diets for a variety of aquatic species including Pacific threadfin (P. sexfilis), mahimahi (C. hippurus), tilapia, Pacific white shrimp (L. vannamei), and the disk abalone (Haliotis discus hannai). OI has a fully integrated research program with a variety of analytical equipment and facilities used to determine nutritional requirements, digestibility, diet palatability, and biochemical analyses of feed ingredients, formulated feeds, and body composition of aquatic animals. In addition, OI has an extensive platform of tanks and aquaria to test novel feed formulations for a variety of target species, as well as a feed digestibility and attractability laboratory. Currently, OI scientists are characterizing and evaluating locally sourced plant and animal products as potential ingredients in an effort to develop feed formulations which promote healthy, fast-growing livestock and aquatic animals for Hawaii’s farmers. As part of this effort, OI is constructing a Feeds Research and Pilot Production Facility in Hilo, Hawaii which is designed to produce commercial quantities of terrestrial and aquatic animal feeds using locally sourced ingredients. Many of these ingredients will come from dedicated supply chains generated by local agriculture businesses, as well as from slaughterhouse and seafood processing waste which currently is being discarded into overburdened landfills. The new feed mill will allow Hawaii’s farmers to use locally produced animal feeds with an expectation that this will help revitalize their businesses by reducing the financial burden they face by having to import animal feeds into the State. Ultimately, these efforts will help move Island residents towards greater food self-sufficiency and enhanced food security.

Training and Education Department Historically, OI has worked closely with public and private schools in Hawaii to introduce young adults to the fields of aquaculture, marine science, and environmental conservation. OI has hosted educational tours for school children of all ages and has conducted hands-on aquaculture and marine science workshops for Hawaii high school students, as well as students from the U.S. mainland. From 1993 – 2007, OI conducted annual workshops for teachers and students from Waianae High School’s Marine Science Learning Center and these workshops reached more than 750 students and teachers during the 15-year run. Currently, OI is launching a series of training and education initiatives which leverage OI’s research accomplishments in aquaculture, aquatic feeds development, marine conservation, and molecular genetics. These initiatives will target a diverse group of participants including young professionals currently involved in aquaculture or related industries, local secondary school students and teachers, undergraduate and graduate students from Hawaii Pacific University and other U.S. universities, and international stakeholders from the private and public sectors. A particular area of focus will be to use aquaculture as a platform for Science, Technology, Engineering, and Math (STEM)

Specific pathogen free (SPF) broodstock (Litopenaeus vannamei) from OI’s shrimp breeding program. OI’s shrimp have been selectively bred for rapid growth and high survival under commercial growout conditions in Hawaii and Asia.

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R&D Centers

Dr. Zhi Yong Ju, Research Scientist, analyzes feed ingredients for amino acid composition in OI’s biochemical lab. Characterizing the nutritional profile of potential feed ingredients is an important part of the work done by OI’s Aquatic Feeds and Nutrition Department.

education. This initiative will allow students to interact directly with aquaculture experts from OI and will provide hands-on experience working with shrimp, fish, and other marine organisms. This non-traditional setting will enable students to more easily grasp complex scientific principles, techniques, and methods than when presented through lectures in a traditional classroom setting. Infrastructure to support OI’s training and education initiatives includes the Oceanic Learning Center with multiple classrooms, a computer lab, and an adjacent outdoor microcosm laboratory.

In addition to the four departments, OI has a new, state-of-the-art molecular genetics building containing two research labs, one teaching lab, and a distance learning center. Research labs are equipped with standard molecular biology equipment to allow for DNA/RNA processing, amplification and quantification, gene expression studies, capillary sequencing, microscopic fluorescent imaging, and bioinformatic analysis. Currently, the research labs are used for microsatellite marker and SNP analyses for pedigree tracking in support of OI’s shrimp breeding program and to characterize microbial flora colonizing the digestive tracts of coral reef fish. In addition, the labs are being used for environmental DNA (eDNA) research to monitor the presence or absence of invasive and endangered aquatic species, both in Hawaii and on the U.S. mainland. The fully equipped teaching lab is used to support training workshops on water quality analysis and the use of molecular biology tools. Recently, with funding from the U.S. Department of Commerce, National Oceanic and Atmospheric Adminis-

OI’s indoor clean lab where controlled, replicated experiments are conducted to assess novel feed ingredients and feed formulation on a number of target species including Pacific threadfin (Polydactylus sexfilis), Pacific white shrimp (Litopenaeus vannamei), and tilapia.

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tration, OI conducted several handson workshops titled, “The Use of Molecular Tools in Marine Science.” Workshops were designed for earlycareer, marine science professionals, secondary school teachers, and university graduate students pursuing degrees in marine sciences.

Center for Tropical and Sub- tropical Aquaculture (CTSA) OI is also the administrative home of the Center for Tropical and Subtropical Aquaculture (CTSA). CTSA is one of five regional aquaculture centers in the United States established by the U.S. Department of Agriculture in 1986. CTSA’s research, extension, and education initiatives have resulted in the development and expansion of the aquaculture industry in Hawaii and other Pacific Islands communities. CTSA’s regional impacts include disease mitigation, sustainable aquatic feeds development, and propagation of new species. For more information about CTSA, please visit their web site at . Over the past 50 years, OI has contributed to many technological advances in marine aquaculture. During a recent 5-year period, OI scientists published more than 75 articles, book chapters, and conference proceedings in various scientific and industry publications and provided more than 100 presentations at scientific and industry conferences in over six countries. All of OI’s departments rely on science-based problem solving to address some of the most complex and pressing challenges faced by the global aquaculture industry. Through OI’s efforts in research, development, technology transfer, training, and education, OI will continue to be a world leader in the advancement of sustainable aquaculture technologies and contribute to a range of solutions to overcome current and emerging industry challenges. Please visit us at our Facebook page at www.facebook. com/Oceanic-Institute-of-Hawaii-Pacific-University522631751248234/timeline to view updates of our most recent achievements and events.

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Aquaculture Industry

Shows Talent in Developing Fish-Free Feeds Michael Tlusty, Ph.DA, Rick Barrows, Ph.DB, and Kevin Fitzsimmons, Ph.D.C

“The future of aquaculture will be heavily dependent on the availability of adequate feed. Sources of fish free feed will be an absolute necessity if aquaculture is to keep pace with growing global demand for seafood,” said Chris Lischewski, President and CEO,


he Fish-Free Feed (F3) Challenge was launched to provide a framework for the creation of aquaculture feeds containing alternatives to fishmeal and fish oil, so that aquaculture can continue to grow, even if wildcaught resources dwindle. The F3 Challenge is an X-Prizestyle competition, where contestants must demonstrate progress toward an ultimate goal of 100,000 metric tons of fish-free feed by September 2017.1 Sponsors include the University of Arizona, Monterey Bay Aquarium, New England Aquarium, and the World Bank. This contest was launched on Nov. 9 2015, and 16 companies from around the world registered to compete, of which eight passed the first milestone in September 2016 by submitting 1 kilogram of feed. F3 Feed Contestants - AgriProtein & Abagold, South Africa - Guangdong Evergreen Feed Industry Co., China - Htoo Thit Co. & Biomin, Myanmar - TomAlgae, Belgium - JAPFA Feeds, Indonesia - Oryza Organics, Pakistan - Ridley & Sureerath Prawns, Australia - TwoXSea, Star Milling Co., Alltech & TerraVia, USA

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Bumblebee Seafood. The F3 Team organized a “Feed Companies Got Talent” networking meeting on January 9-11th 2017 in the San Francisco Bay Area, moderated by Dr. Kevin Fitzsimmons of the University of Arizona to help contestants boost their sales, network, and pitch to aquaculture investors. In addition to the contestants, invitees included world-renown experts, high-tech companies, investors, alternative ingredient providers and some of the largest aquaculture and aquafeed companies in the world. In western countries, consumers may be willing to pay for a high-quality delicious fish at a higher cost. This is the model chosen by TwoXSea founders Bill Foss and Kenny Belov, whose

All attendees at the F3 Challenge meeting.

restaurants serve up farmed trout that are fed an environmentally responsible vegetarian diet, giving their fish a longer shelf life. Bill Foss, who presented TwoXSea’s business model to attendees, highlighted the importance of switching to F3 and believes that people will be willing to pay “less than a large latte at Starbucks” on a sixounce portion of high-quality protein because of the health benefits associated with it. In contrast, May Myat Noe Lwin, technical manager at the U.S. Soybean Export Council speaking about Myanmar feed company Htoo Thit, presented a different perspective. Despite currently being unable to export product to the U.S., Htoo Thit is joining

Dr. Kevin Fitzsimmons at the F3 Challenge meeting.

the F3 effort by incorporating soybean meal from the U.S. in their feed and is working with the ingredient company Biomin to incorporate additional fishfree ingredients. The roadblocks for Htoo Thit, in addition to current U.S. import sanctions, are skeptical fish farmers whose first step upon feed delivery is to open a bag and check it for the familiar “fish smell.” Including these farmers in the F3 discussion, as well as education, will be essential to overcome this barrier. Dr. Rick Barrows pointed out that people seeking alternatives for replacing fish meal will need to use dozens of components, rather than fewer ingredients, so that F3 feeds can provide nutritional equivalence. There was also respectful disagreement on the sustainability of fishmeals and oils and the need to replace them, simply reduce their use, or use only those based on byproducts. Additionally, there was some discussion about the misperception that replacing fishmeal and oil is necessarily environmentally responsible. For example, if more land needs to be cleared to grow more soy in order to feed fish, or if plant-based options are grown in an indoor production facility that takes energy to operate, then the solution to one problem may cre-

ate problems elsewhere. The purpose of this competition is to highlight the current ability of the aquaculture industry to be fishmeal free, and to create discussion on how to move the industry forward as a step towards a more comprehensive approach to sustainability. A subsequent competition (F4) is in the works. The last evening featured a kickoff dinner to encourage the participants in the middle of the contest to ramp up sales of their F3 Fish-Free Feeds. The keynote speaker, technology business entrepreneur David Evans Shaw, inspired the audience as he spoke of the many businesses he had founded in areas that were previously considered technologically impossible, including IDEXX. David Tze of Aquacopia announced the launch of a new search fund with a pro-F3 focus that shows promise given his previous experiences co-founding Aquacopia, that in turn launched Open Blue, InnovaSea, and iCell/Nutrinsic, putting approximately $200 million USD in capital to work. A large show of industry support was unveiled as several large companies announced that they would conduct feed trials of F3 feeds for the species relevant to their aquaculture operations: Alpha Feed, Dainichi,

Regal Springs, and Marine Harvest. Marine Harvest announced that their feed trial was valued at $150,000 USD. Other large company attendees have F3 trials under consideration. During the final day, a breakout session was held where participants strategized on how best to spread F3 innovation: If a Feed Innovation Network were to be developed, how should it be structured to spur innovation by geography yet be connected globally? The group outlined that cost and connection with traditional fish-feed developers were important factors, even though the environmental and human health benefits of numerous fish-free alternatives, free of PCBs and other toxins, would seem advantageous to many. As the many great ideas for the creation of a Feed Innovation Network are still being discussed, the spirit of the network was captured through one participant’s summary: “Today, we continue to need the ocean to feed the animals that we eat. And a growing global population that is moving out of poverty means that we will shortly need 50 million more tons of fish. Unless our human ingenuity can pioneer new ways of feeding the animals we need to eat, there will be no more fish in the sea. We will work tirelessly to bring together those with ideas and solutions to create renewable and sustainable ways to feed our planet. We will engage those with vision and those with the means to transform that vision into reality so that together we create a tomorrow where we have the means to nourish both our planet and our children. Our determination will not wane to identify, curate, nurture and inspire those who are pioneering and scaling the solutions for sustainably feeding our growing global population. For we know that only when we, the innovators, producers, investors, scientists and dreamers, all come together as equals can we hope to succeed.” If no contestant has reached this goal, the winner will be the one that is the furthest along by the contest end date of September 2017


Chris Lischewski, CEO of Bumblebee Seafood.

A New England Aquarium’s Anderson Cabot Center for Ocean Life and University of Massachusetts at Boston’s School for the Environment B Aquatic Feed Technologies, LLC C University of Arizona

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It’s good to promote the consumption of fish and seafood,

but it’s also important to promote and ensure production. In 2016, the FAO announced that the world consumption of fish per capita surpassed 20 kilograms per year for the first time. According to the report, this is due to “an increase in supply provided by aquaculture, By: Salvador Meza

and also to the force of world demand.”


n practically all countries in the Americas, as well as in many other countries of the world, the ministries in charge of the fishery and aquaculture pipelines have taken up the tendency to promote the consumption of fish and seafood as a permanent campaign standard. They continuously give out declarations in favor of the benefits of consuming these products, and invite the population in general to consume them, both at inaugurations and public acts, as well as in regular and accountability reports for legislative congresses and parliaments. Pursuant to this tendency, on November 15, 2016 the “Sub-Regional Forum on the Inclusion of Fish in the School Meal: Generating a Multisector Strategy for the Countries of Central America” was carried out in Panama City, Panama. This event was organized by the FAO, by the Panama Ministry of Education and by the Panama Ministry of Health. The Forum, which addressed the authorities responsible for School Meal Programs in Belize, Costa Rica, Cuba, El Salvador, Guatemala, Hon44 »

duras, Nicaragua and Panama, had the goal: “to learn about successful experiences regarding the incorporation of fish products in school meal programs in Latin American countries and The Caribbean”. Without underestimating this effort, by no means whatsoever, it seems to me that we would also have to concomitantly organize Forums

to inter-institutionally analyze how to produce more fish and seafood within the region and the Americas. Because in the long run, the increase in the consumption of fish and seafood will result in an increase in the import of aquaculture commodities from around the world -in other words: tilapia, basa (Pangasius), shrimp and

salmon - which will end up increasing the alimentary deficit of each country because the imported products, in many cases (such as with tilapia, shrimp and catfish), could very well be produced locally. The Fishery and Aquaculture ministries of the countries in the American continents should pay more attention to their technical cadres, especially regarding aquafarming production. The fact that the discussion of the orders of business of these ministries is charged towards the promotion of fish and seafood, instead of being oriented towards the production and industrialization of these products -especially in these countries that have a well-known backlog regarding aquafarming production- is nothing more than a symptom of the lack of professionals in aquaculture within the directive cadres of these ministries. There are many factors that explain this absence of aquaculture

professionals within the operational structures of these governmental institutions. One could be the fact that aquafarming technicians and producers are not given to politics, and are absorbed in their field work, so they do not pay attention to the social connections with politicians that can invite them to occupy an important decision-making position within the bureaucracy. On the other hand, the politician that gets to occupy directive positions within the fishing and aquaculture ministry has no knowledge nor the necessary experience to be able to distinguish among his collaborators, or even outside the institution, those persons that can technically develop a department to accelerate the aquafarming production of the country on call. They easily fall into the hands of resourceful and coherent charlatans that, far from promoting production, become obstacles when they end up as victims of their

own tall tales and lies, thinking they know everything and driving away the people that definitely understand the topic. A possibility for breaking up this vicious circle is having third parties, on behalf of the public institutions, compete for these technical positions for the development and industrialization of aquaculture. Through an open call, carried out by one or several companies specializing in personnel recruitment, one could select the professionals that can set the basis for aquafarming development and industrialization of the production pertaining to each country of the region. And then, it will be “yes… now on to promote consumption!”

Salvador Meza is Editor & Publisher of Aquaculture Magazine, and of the Spanish language industry magazine Panorama Acuicola.

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The Risks to Healthy Fish: Part 2

Hugh Mitchell, MS, DVM AquaTactics Fish Health

A useful tool available to aquaculture producers is the Odds Ratio, a number representing the association between a disease and exposure to a risk (e.g.: density, temperature, proximity, water quality, etc.) er, Halal Gluten Free, Kosh redients, No 100 % Delicious: Ing l cia tifi Ar No G, No Dairy, ts, or Trans Fat Fa ed at Non GMO, No MS en ing, No Hydrog lor Co or rs vo Fla Artificial

Figure 1. Targeting the risk-averse: some product labels imply that every other choice is riskier. In the real world, however, odds ratio analysis provides an objective tool for risk-averse aquaculture producers.

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Table 1 An Odds Ratio is an estimate of relative risk. Below is a simple illustration. DISEASE CASES EXPOSED TO RISK NOT EXPOSED




How to interpret: “Fish exposed to risk are AD/BC times more likely to be diseased than those not exposed.” A farm, net pen, raceway, tank, etc. is described in 2 dimensions: (1) as having the disease or not, and (2) as being exposed to some hypothetical risk or not. There hasn’t been a great deal of risk analysis work done in aquaculture, relative to agriculture, especially in terms of practically applied odds ratios. Despite this, the four examples below introduce the concept with the intent that farmers and fish health professionals consider adding this useful tool to their arsenal. EXAMPLE 1: Factors involved with Infectious Salmon Anemia risk in farmed salmon Infectious salmon anemia (ISA) is a very serious disease in farmed salmon in the Atlantic and in Chile. Jarp and Karlsen (1997) investigated several potential risk factors with the goal of identifying factors that would help farmers understand why some farms were more impacted than others. They looked at 74 sites along the coast of Norway: ½ were ISA positive and ½ were negative (Disease case=ISA positive; Non Case=ISA negative). Through a questionnaire, they obtained information on potential risks including: type of site, management practices, location relative to processing plants, hygiene, near-by processing plant practices, etc. Sea cage site was found to be a significant risk factor, in terms of proximity to a processing plant. A farm was 13X more likely to be ISA positive if it was within 5

km of a processing plant compared to farms that were further away. If closer than 5 km to another ISA positive site, risk increased by 8X. For those sites less than 5 km from processing facilities, if plants did not have water disinfection systems risks increased by 14.6X, compared to only 1.6X when processing water disinfection systems were in use. The type of disinfection system did not seem to matter. Risk was 2.6X greater if a sea cage site received fish from more than one hatchery. This is similar to terrestrial animal production where multiple sources of young animals added to a finishing facility increases the risks of many diseases. More distant hatcheries as sources were 3.3X more likely to be associated with ISApositive sites. Other risk factors were sifted out and the paper provides a very good example of how useful this type of analysis can be. The bottom line was that the virus is spread through seawater and farms have to concentrate on minimizing the risk

of transmission through seawater, eliminating positive sites as quickly as possible, and ensuring that all processing plants have disinfection systems. Most of this might be considered “common sense”, but odds ratio analysis confirms and quantifies. Surprising factors found not to be significant are important findings in and of themselve. Sharing personnel between sites, sharing equipment, and dead fish removal frequency in the winter (not the summer!) were found not to be important risks for ISA infection.

EXAMPLE 2: Factors involved with Bacterial Gill Disease risk in farmed rainbow trout Bacterial Gill Disease (BGD), sometimes associated with Flavobacterium branchophilia, is a common and costly problem for both commercial and stock enhancement facilities in North America, with wide differences in impacts between trout hatcheries. Bebak, Baumgarten and Smith published the

results of a study in 1997 that looked at what factors put facilities at risk to BGD. Significant risk factors included: history of BGD (10X); being a commercial facility (5X); and size – greater than 250,000 fish annually (3X). For BGD outbreaks in the hatch house, the risks were: fish in the source water supply (5X increase); use of ultraviolet radiation to disinfect hatch house water (7.5X); history (19X); and being commercial (8X). Outside of the hatch house, the most significant factors were: history (4.3X) and size (greater than 50,000 pounds annual production = 2.5X). This study shows some of the challenges that risk analyses sometimes involve. Associations mean little if one can’t find a sense of biological plausibility. History of BGD makes sense (“more begets more”) and speaks to the necessity of resetting the facility and looking at all potential source, husbandry, and management factors. In other words, it is not an easy fix, so time and energy on a simplistic solu-

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tion should be discouraged. As commercial facilities seem to be more of a risk than government ones, this may speak to intensification and the continual push on commercial facilities to improve margins through cutting corners (staff, equipment, husbandry protocols, etc.). Why UV disinfection would increase risk, may hint at what the source is, the lack of effectiveness of UV on the bacteria (or question of a bacterial etiology), or the search for a simple cause, when there isn’t one (see above).

EXAMPLE 3: Factors involved with Enteric Septicemia of Catfish risk in farmed catfish The most serious disease of the larg-

est aquaculture industry in the U.S. is still Enteric Septicemia of Catfish (ESC), associated with the bacterium Edwardsiella ictaluri. There is also wide variation in when and how severely ESC affects ponds within and between farms. Cunningham, et al. (2014) looked at potential risk factors in catfish ponds that may have been associated with the disease or resulted in variations in impact. Two of the significant odds ratios and factors included: Nitrite and Total Ammonia measured within 14 days of outbreak (3X and 20X, respectively). The conclusion is that at-risk ponds might be identified prior to an outbreak and prevention steps taken, such as curtailing feeding and increasing aeration

Figure 2. Typical external gross lesion signs of a Enteric Septicemia of Catfish (courtesy of Dr. Lester Khoo).

Figure 3. Typical gross lesion signs of a Salmon Rickettsia Syndrome in a farmed Atlantic salmon liver and kidney.

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following spikes in Nitrite or Total Ammonia.

EXAMPLE 4: Factors involved with Salmon Rickettsia Syndrome risk in farmed salmon Salmon Rickettsiosis is a disease that is endemic to Chile. In a study that looked into the factors that affect the variability of impacts on salmon and trout farmers, Jakob et al, (2014) looked at factors from 25 farms with the objective of determining which were most associated with disease severity. Other statistical tools and modeling were used to sift out various high risk trends and some interesting findings are presented. Odds ratios were calculated (from regression coefficients) for different vaccine strategies. A “disease case” was defined as high SRS mortality (>3 %) vs. a “noncase” with low SRS mortality (<3 %). Four vaccines and vaccine strategies were included, plus these additional factors: cumulative mortalities within first 4 weeks (early mortalities) and starting weights (smolt size). Odds ratios ranged from only 1X to 2.8X, with most vaccines and weight or initial mortality showing little risk. One vaccine strategy was 2.8X more likely to produce a non-case (a sort of reverse odds ratio), but no odds ratios were significant from each other. This study verified the feelings of farmers that vaccines were probably not doing much. A point was made by the researchers, that none of the odds ratios were significantly different, indicating that more farms in the study (more variation and factors) might have allowed for a better detection of what factors were important. This is an important point. Odds ratio analysis works best and yields the most satisfactory results IF there are enough participants! Cooperation between sites and farms helps everyone. Practical Use of Odds Ratios on Your Farm The above examples illustrate how odds ratios work in fish farming, but almost all suffer from not incorpo-

rating practical day-to-day measures that farmers can employ. So, how might a farmer take advantage of quantifying risk to better map out what are the most relevant risks on which to concentrate? First, this should be a cooperative effort between the culturist, the fish health professional, and a statistician (the latter if necessary). The more sites, the more accurate the risk estimate, and a large farm with several sites or cooperation between facilities is required. First attempts should not be too ambitious (“Keep It Simple”). Pick a major disease that is both endemic (always there) and of common interest to all, and decide on one or more outcome measures. This should take a dedicated sit down session or two, in order that the most relevant risks are identified as possible candidates. The trick here is that the information has to be binary: “yes-no” or “this or that,” for both the disease and the factors. For example: disease cases vs. non cases

being something like: “mortalities greater or lesser than X percent,” and risk exposure being: “above or below a certain raceway density.” Once the data has been analyzed it is important to have a debriefing and try and make collective sense. Again, statistics are merely a presentation and significance and resultant actions are determined by things such as: magnitude of odds ratio; biological plausibility (“does it make sense”); correct sequence of events; repeatability; and dose response (if a factor comes out significant, does “more produce more”?). By using this simple statistical technique (and some more sophisticated offshoots) we can become risk averse about the right things in aquaculture health management. With the correct amount of risk aversion (ranked and numerically quantified), we can be more solidly guided versus a “subjective or experienced hunch.” This tool can help steer a fish farm operation, or an entire industry, to-

ward the appropriate resources and the correct amount of time and energy required for the reduction of identified significant risks - with the end game of making real differences in on-farm disease impacts.

Hugh Mitchell, MS, DVM is an aquaculture veterinarian with more than 25 years of experience, who provides services and fish health tools to fish farmers across the US and Canada. His practice is AquaTactics Fish Health, out of Kirkland, Washington, specializing in bringing a comprehensive professional service/product package to aquaculture, including: vaccine solutions, immune stimulants, sedatives, antimicrobials and parasiticides. website:; contact:

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TILAPIA & Genetics and Breeding

Genetic Influences Over Disease Resistance

By Greg Lutz*

In virtually all types of aquaculture throughout the world, whether artisanal or industrial, inland, coastal or marine, disease issues and health management present serious challenges for producers. The question of genetic improvement of resistance to diseases is often posed, for a variety of aquatic species. Unfortunately, in many cases there has not been enough research to date to provide clear or immediate responses to these concerns. This research is progressing, however, and it will continue to provide strategies and the means to greatly improve the hardiness of many cultured fish, crustaceans and mollusks.


n practical terms, the most common approach to improving disease resistance is to save those individuals that survive disease outbreaks and use them as breeding stock. This strategy, however, provides little insight into underlying genetic control, and may often be of little use if the heritability of resistance is low. Evaluating disease resistance through studying its inheritance might seem fairly straightforward, but it can be extremely complicated from a statistical standpoint. If an individual animal succumbs to a disease challenge, it is no longer part of the breeding population (except perhaps in the rare instances where sperm has already been stored from male animals), so there is a built-in asymmetry when looking at inheritance over several generations. As a result, it is often necessary to conduct selection on family groups, where a representative sample of the individuals in question is subjected to a disease agent and survival data is used to estimate the “resistance” of the remaining, unchallenged animals within the original family. Even in this type of situation, where resistance of family groups or 50 »

populations must be judged by the performance of representative samples, there are various ways to handle survivorship data and its analysis. In some situations, the best approach is to handle disease resistance as a “threshold trait.” Basically, what this means is an individual died or it didn’t, but the data for the group as a whole is handled as if there were an underlying distribution of survivorship, commonly a normal distribution. Many classic texts in animal breeding, quantitative genetics and statistical analysis provide the equations required for this transformation. In other situations, resistance is measured as time of ex-

posure up until death, with a longer survival time equating to higher resistance. This type of data can usually be handled more directly in statistical analysis, but it may only have partial relevance in terms of survival or death. Henryon et al. (2005) examined the utility of selecting for increased resistance to enteric redmouth disease, rainbow trout fry syndrome, and viral haemorrhagic septicaemia in Onchorhynchus mykiss. They produced 63 full-sib families of trout and exposed portions of each (separately) to the bacteria and virus that cause the diseases in question. For each trait,

resistance was quantified as either a threshold (i.e., death or survival) and a continuous variable (time until death following exposure). Statistical models were developed to assess the inheritance of resistance based on each of these approaches, with heritabilities ranging from 0.42 to 0.57 for resistance as threshold traits, and from only 0.07 to 0.21 for resistance based on time to death. Clearly, the statistics available to examine genetic control over resistance are somewhat simplistic, and not always in agreement. Which, if either, of these statistical interpretations of ‘resistance’ is more applicable to the population in question could probably only be determined by evaluating selection responses over time. Another broad group of diseases in aquatic species involves parasitism. Parasites may range from microscopic organisms to something as large as a lamprey, but some of the most insidious and problematic are the salmon lice. Kolstad et al. (2005) examined the susceptibility of Atlantic salmon (Salmo salar) to the salmon louse (Lepeophtheirus salmonis). They used natural sea louse infections in 350 full-sib families of salmon over three year classes to calculate a heritability of 0.14±0.02. Under controlled challenge conditions, heritability was even higher, 0.26±0.07. These researchers concluded that there is significant potential for improving sea lice resistance in Atlantic salmon through selection,

Researchers concluded that there is significant potential for improving sea lice resistance in Atlantic salmon through selection, but that resistance should be evaluated through challenge tests rather than by natural infection rates, which can be highly variable

but that resistance should be evaluated through challenge tests rather than by natural infection rates, which can be highly variable. In recent years, the use of genomic analyses to pinpoint specific genes that enhance resistance has been incorporated in the on-going battle against sea lice. A timeless alternative to animal and plant improvement through selection involves hybridization or crossbreeding, and this approach has also proven of value in improving disease resistance in several aquatic species. The expression of heterosis, where offspring of comparatively unrelated individuals exhibit increased fitness, is the basis for such efforts. On a molecular level, it has been suggested that heterozygotes, which code for two gene products at a specific locus, can adapt more flexible responses to environmental variability than can homozygotes which produce only one gene product. Cai et al. (2004) reported on the comparative resistance of Nile tilapia (Oreochromis niloticus), blue tilapia (O. aureus), and their hybrid to the bacteria Aeromonas sobria. They examined a number of indicators of resistance, including median lethal dose of bacteria and various nonspecific immune functions. While blue tilapia exhibited lower resistance than Nile tilapia, hybrids were most resistant to disease caused by A. sobria. Similarly, Bosworth et al. (2004) reported significant heterosis for survival and antibody levels in three strains of channel catfish (Ictalurus punctatus) following exposure to the bacteria Edwardsiella ictaluri. Much work continues in the area of identifying Quantitative Trait Loci (QTL’s) related to disease resistance in various aquatic species. QTL’s are simply genes that have significant influence on “continuous” traits such as weight gain, fecundity, age at maturity, etc. etc. etc. Although many genes may be involved in such a trait, QTL’s represent those loci which exert the most influence, perhaps accounting for 20 to 50 percent of the observed

phenotypic variation. It is usually not possible (at least not initially) to identify a specific, individual QTL on a chromosome, but researchers have learned to use closely-linked markers to provide a rough idea of where QTL’s can be found. Rodriguez et al. (2004) were among the first to examine genetic markers associated with disease resistance in rainbow and steelhead trout (O. mykiss). They constructed linkage maps for sires and dams to allow for associations between markers and QTL’s related to resistance to infectious hematopoietic necrosis virus (IHNV). In the dam linkage map, 12 markers were associated with IHNV resistance, distributed across 6 distinct linkage groups. In the sire map, 22 markers in three linkage groups were associated with IHNV resistance. Of these 22 markers, six were microsatellite markers and these were used to screen nine other families. However, only four were associated with QTL’s in one or more of the nine families. These results suggested that additional marker mapping would be required to improve the identification of QTL’s for marker assisted selection. Clearly, there is much work still to be done but the work of combining traditional genetic improvement with modern molecular identification of QTL’s is ongoing. Further advances in efficiency can be anticipated as genomic methods allow us to evaluate which genes are up- or down-regulated in response to disease challenges.

Dr. C. Greg Lutz is the author of the book Practical Genetics for Aquaculture and the Editor in Chief at Aquaculture Magazine.

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Aquaculture Stewardship Council


Announces Interim Feed Solution


he ASC standards cover a wide array of impact areas, mainly focusing on environmental and social issues. ASC has seen a rapid uptake of its standards by farms globally and as such is helping to reduce the impact challenges the industry is facing. At the same time we are seeing an increasing interest from the market, which spurs even more farms to adopt responsible practices and enter ASC certification which in turn reduces the industry’s impact even further, in line with ASC’s mission. However, the availability of fish meal and fish oil ingredients to meet the ambitious requirements set out in the ASC Farm Standards (to reach certification against an ISEAL member scheme), has not developed as quickly as was anticipated by the Aquaculture Dialogues. Furthermore, some major (feed) fisheries have not moved towards MSC- certification as fast as expected. As a result, there is insufficient availability of fish meal and fish oil that meets the requirements as set in the ASC Farm Standards. At the same time, the interim requirements (a Fish Source Score of A or B1) described in the ASC Freshwater Trout, Salmon and Shrimp Standards, face a similar supply issue. These two realities create immediate compliance challenges for ASC-certified farms as well as for those preparing for certification assessment. Non-compliance of these requirements will result in the loss of, or failure to achieve, certification. This will not only slow down the further uptake of ASC certified products in the market, but will reverse the current successful market position gained, removing the incentives created that are promoting industry’s move towards more sustain52 »

On December 13, the Aquaculture Stewardship Council (ASC) announced the launch of an Interim Solution for the marine raw material used in feed. This Interim Solution replaces the current set of requirements for marine raw material in the ASC Farm Standards. able practices. At this juncture, early in the development of ASC as an independent organization, this creates a serious challenge to its long-term viability. The Interim Solution increases the amount of marine raw material available for use in feed at farms certified to the ASC Farm Standards for salmon, tilapia, pangasius, trout, shrimp, abalone, seriola and cobia from 21 September 2016. In addition to this interim solution, the ASC is developing a separate ASC Feed Standard. The new standard will also supersede the current ASC requirement that all whole fish, fish meal and oil used in the feed must be fully ISEAL certified within 5 years after the release of each standard. The Interim Solution requirements bridge the gap between the current marine raw material requirements in the ASC Farm Standards and the release of the separate ASC Feed Standard. The policy requires farms in the programme to use marine raw materials categorised as A-B2 by the Sustainable Fisheries Partnership’s (SFP) Fish Source Score. “The Interim Solution continues to promote responsible sourcing of marine raw materials for feed, but it also takes into account the shortfall between the rising demand for sustainable raw marine ingredients with the current shortfall in the supply,” said Michel Fransen, Standards and Certification Coordinator, ASC. However, the interim solution announced in December and the new standard under review both estab-

lish protocols that balance the need for more sustainable feed with the ability to secure marine raw materials that meet the requirements. With these updates, the ASC hopes to incentivize more feed fisheries to improve their sustainability by achieving ISEAL certification of the whole fish, fish meal and fish oil used for feed. Without these improvements fisheries cannot supply these feed components to ASC certified farms in the future. The full and final ASC Feed Standard is anticipated in Q4 2017 and will address overall ingredient origin requirements, as well as feed mill performance. An initial draft of the full Feed Standard has been shared publically and a second draft will be available for public comments in Q1 2017. More information on the interim solution for the feed marine raw material requirements can be found at ASC Staff

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Recent news from around the globe by

These are some of the highlights of the past few weeks at

By Suzi Dominy*

Partnerships offer promise for new aquafeed solutions There has been a lot of enthusiastic talk about insects as a sustainable protein source for aquaculture feed, and with good cause. As well as being an excellent nutritional source, insects such as fly larvae or mealworms are easy to breed and can be fed with organic waste. They are remarkably efficient at converting feed into protein and require little space to cultivate. Because of these advantages, insects have attracted considerable attention from startups and established players in the food industry in recent years, as we have mentioned more than once in this column. However, as with other emergent feed sources, availability, consistency, technical issues and authorization have all been hurdles, but now it looks as though some of the road blocks are falling, and commercially available insect protein is set to take a major step forward. At the end of 2016, the Council of the EU voted to permit insect protein as a feed in EU aquaculture. Outside the EU, AgriProtein reports they will soon be capable of recycling 250 metric tons of domestic organic waste per day, into insect protein. A development of special interest to the aquafeed sector is the formation 54 »

Insects at Bühler R&D lab (Source: Bühler Group)

of a joint venture between two leading players in insect production and feed and food engineering respectively: Bühler Insect Technology Solutions, founded by Swiss company, Bühler and Netherlands-based Protix, will develop scalable, industrial solutions for the rearing and processing of insects for feed. “Protix is the most advanced insect company that has demonstrated industrialscale production in a way that is scalable and multipliable. They have proven how to create a market in insect protein,” ex-

plained Ian Roberts, CTO of Bühler. Now they are ready to take the company to the next level and need a partner who understands the requirements of large, industrial processors. This is where Bühler comes in: The Switzerland-based technology and solution provider can look back on more than 150 years of experience in developing scalable, cost effective, hygienic plants and processes for food and feed products. Bühler is also the recognized technology leader in milling, which is one of

Coppens International feed innovations for 2017 Since we reported the acquisition of feed company Coppens International by biotech firm, Alltech, last year, the company has been busy. Collaboration between the companies’ research teams has resulted in a wide range of projects. These projects include the introduction of several new algae products containing innovative Alltech technologies, such as a sustainable algae-derived fish oil replacer containing very high levels of DHA omega-3 fatty acids, to the Coppens International aquatic product range. Gijs Rutjes, technical sales support manager at Coppens International said that test results show that by completely replacing fish oil with the algal oil, they have been able to transfer a high amount of DHA omega-3 into the fish. A new trout feed will be the first product to be introduced that contains the algal oil. Other Alltech aquaculture technologies that are now incorporated into the Coppens aquafeed range inExploring marine by-catch clude products that increase growth Aquafeed company BioMar has and weight gain as well as improves joined forces with Aker BioMarine, gut health and immune function; a Pelagia and Norsildmel and research product based on yeast cell walls, organizations Nofima, the Univer- which supports the immune syssity of Bergen and the University of tem and the overall health of the California Los Angeles in a project fish, and also functions as a growth to unlock the nutritional and techni- promoter; and a health, growth and cal quality potential of marine by- performance enhancer for fish, usproducts in sustainable salmonid ing organically bound trace elements feeds. The QMAR project started such as zinc, copper, manganese and up in January 2017 and is supported iron. by the Research Council of Norway. According to Hanne Jorun Sixten, Hatchery feed magazine is Senior Researcher at BioMar’s glob- growing al R&D Nutrition Requirements Information about early lifestage Group and QMAR project manager, feeds is sorely needed, as interest in the project will enable BioMar and our website and its partners not only to develop in- publications has shown. So from gredients and feed products based 2017 we will increase the frequency on these waste-stream products, but of the magazine to four times a year. to study the mechanisms underlying We will also split the annual feed the beneficial effects of their com- guide into dedicated product direcponents. tories. Do you have information to the key process steps for extracting protein from insects. Additionally, Bühler supports customers through its global service network. Bühler Insect Technologies is located in Liyang, China, and has already begun operation. The goal of the joint venture is to develop industrial scale solutions for feedstock processing, larvae rearing and larvae processing, and to produce highquality insect ingredients – covering the whole value chain from rearing to separation and extraction of proteins and lipids. Initially, the focus will be on larvae of the Black Soldier Fly, nicknamed the “Queen of waste transformation” for its impressive ability to transform organic waste products into high-quality protein. Subsequently there will be a diversification to other insects, such as mealworms. The insect proteins will be used primarily for the production of sustainable feed. The company projects that by 2050 insects could account for 15 % of global protein production.

Coppens International production facility, Nettetal, Germany. (Source: Alltech)

share on manufactured hatchery feeds, feed production, feed management, early lifestage and broodstock nutrition or other feed related topics of interest to hatchery managers? The Feb/March issue will focus on live feeds and conditioners: such as zooplankton, phytoplankton, enrichments for rotifers and Artemia, water conditioners and microbial products. It will also cover the important areas of feed management, nutrition, and live feed production systems. The Directory of Live Feeds and Enrichment Products will be included in this issue. Contact me at for details if you would like to contribute editorial or to advertise in any of our issues. Subscription is free - sign up from or

Suzi Dominy is the founding editor and publisher of She brings 25 years of experience in professional feed industry journalism and publishing. Before starting this company, she was co-publisher of the agri-food division of a major UK-based company, and editor of their major international feed magazine for 13 years.

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Nutrition “So I got into growing grapes, not realizing that there was a heck of a lot By: Paul B. Brown*


at Paulsen’s description of growing grapes also applies to aquaculture. How many times have we had conversations with people interested in aquaculture, but those folks have not explored the details? Nutrition can also be described this way. In this forum, we have considered some of the complexities of nutrition internally, but what about externally? Does fish feed have impacts beyond the target animal? One of the more obvious areas where the initial feed going into an aquaculture system exerts impacts externally (beyond the target organism) is in nutritional content of the finished product. A broad sweeping generalization in all animals, and in aquatic animals in particular, is that the feed influences the final fatty acid concentrations. N-3 fatty acids (also referred to as omega-3 fatty acids) are beneficial for human health. If feeds contain n-3 fatty acids, then the resulting product will also contain n-3 fatty acids. However, there are other areas where fish/ shrimp feed also exerts impacts. In pond environments, nutrients from uneaten feed and feces are taken up by plants (macrophytes and algae)

Figure 1. Depiction of plant nutrient needs.

56 »

more to it than meets the eye.” Pat Paulsen, comedian, 1927-1997 and used for growth, which generates oxygen in the system while removing carbon dioxide. Fish/shrimp feeds are not specifically formulated to meet the nutrient demands of plants in culture ponds, as there are very few examples of nutritional limitations on algae growth in aquaculture ponds. However, as we further intensify aquacultural production by moving into controlled production scenarios indoors and linking aquacultural production to hydroponic plant production, nutrients for plant growth become limiting; fish/ shrimp feeds are not formulated to meet the nutritional needs of intensively reared plants crops. Figure 1 is a depiction of the nutrient needs of plants. There is a good deal of similarity in the mineral needs of plants and those of animals. Despite the similarities in nutritional needs, nutritional deficiencies in plant crops grown in aquaponics systems are common. The more common nutrient deficiencies are K, Fe and Ca. These minerals are in fish/shrimp diets, but the concentrations in water are inadequate to meet the needs of a rapidly growing plant. To be available for plant growth, minerals in the fish/shrimp diet must go into solution (if the feed is not consumed). However, most feed is consumed. Digestive secretions (acid and enzymes) act on the food, some of the minerals are absorbed, and finally the minerals in excreted feces must go into solution. K, Fe and Ca are in these diets, but an inadequate amount enters solution and becomes available to the plant. Water chemistry also has an impact on this nutrient exchange. Figure 2 shows the effect of environmental pH on nutrient availability to plants. Availability of Fe clearly de-

Figure 2. Effect of environmental pH on nutrient uptake by plants.

creases as environmental pH increases to 7 and above. Environmental pH in an intensive recirculating aquaculture or integrated aquaponics system can change significantly over time, impacting nutrient availability. Diets are not currently formulated to meet the needs of plant crops in aquaponics systems and the effects of water chemistry are rarely considered as we teach farmers how to operate these systems for maximum production. However, there are several groups around the world with an interest in improving this situation. In the next contribution, we will consider an additional taxa that must be “fed” via the fish food.

Dr. Paul Brown is Professor of Fisheries and Aquatic Sciences in the Department of Forestry and Natural Resources of Purdue University. Brown has served as Associate Editor for the Progressive Fish-Culturist and the Journal of the World Aquaculture Society, among many others.

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Aquaculture Engineering

Increasing Global CO2 and Ocean Acidification: Part 2

The unpopular but scientifically undeniable truth is that the CO2

concentration in the atmosphere is increasing, as we continue to burn fossil fuels for energy. This will decrease the ocean pH, as we previously discussed. The amount of ocean acidification (OA) is small relative to what we normally deal with in high intensity aquaculture, so who cares about 0.15 drops in pH? Most fish culture doesn’t get into real CO2 trouble until the CO2 partial pressure rises in the percent range. For climate change going from 0.04 % CO2 to 0.08 % CO2 is By Dallas Weaver, Ph.D.*


owever, pH is a log scale and that has apparently dropped the Ωar about 0.5 (Harris, DeGrandpre et al. 2013) since humanity started burning fossil fuels. From an available energy view point, going from a supersaturation of Ω = 2.0 to 1.5 is significant. Recall from the last column that animals such as corals and larval oysters can use chemical energy supersaturation (Ω > 1) to build their shells or skeletons without spending energy pumping ions. Under these conditions, all the animal has to do is produce a small amount of organic material which matches the desired crystal structure well enough for the crystal growth to start. In essence, the animal creates an artificial organic “seed” crystal and gets its shell for a very small energy investment. Normally, pacific oysters go from no shell to having a shell in 6 hours. The shell is 80 % of their total body weight at this stage. Increasing the shell formation time, with conditions resulting in a slower rate, can be lethal. The oyster uses up all its energy 58 »

very relevant but of no significance for fish aquaculture.

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Aquaculture Engineering

before it creates the shell it requires to continue to develop. We can view the crystal surface as constantly laying down molecules and removing molecules. The flux rates are equal at equilibrium (Ω = 1). When Ω >1 there is a net growth, and the actual flow of molecules to the crystal surface is faster than that of the molecules leaving. If we assume the relationship between Ω and the crystal growth rate is R = k(Ω -1), going from Ω = 2.0 to 1.5 could be cutting the growth rate in half. From a nucleation viewpoint, the more soluble amorphous form of CaCO3 is easier to form at very small sizes (a common observation (Stumm and Morgan 2012)) , but the Kam for the amorphous form is larger than Kar for the aragonite form. If this amorphous form is the initial form of CaCO3 used by this oyster species, this small change in supersaturation can be even more critical with Ωam ≅ 1 where no growth oc60 »

curs at an aroganite Ωare ≅ 1.5 or so. To get growth, the animal has to spend energy pumping ions to get a local volume with a high Ω.

Mystery solution The oyster industry got together with seawater chemists and other researchers at universities (Barton, Waldbusser et al. 2015) and conducted measurements that showed that low supersaturation (low Ωar) was the primary cause of the culture failures, due to high CO2 water that came into the bays and hatchery intake water. They used salinity, pH and partial pressure of CO2 (pCO2) to calculate the carbonate concentration [CO3] and the aroganite saturation Ωar. However, the research didn’t answer the question why a simple pH change increasing the carbonate concentration didn’t consistently work, but letting the eel grass increase the pH, by removing CO2, did produce quality water.

The solution to this secondary mystery is related to nucleation at extremely high Ω but very local values where you get rapid homogenous nucleation of billions of seed crystals that rapidly grow and remove the supersaturation. They probably did what I did in the experiment previously described and mixed a strongly basic solution with the input water getting the correct average, but creating massive numbers of very fine CaCO3 precipitates that de-supersaturated their solution. Mixing two solutions always results in large initial concentration gradients and local areas with compositions much different than the average. Passing the input water over the eel grass, when the grass was producing oxygen and consuming CO2 via photosynthesis, slowly removed the excess CO2 and didn’t have any very small local high Ω volumes creating seed. It is difficult to convince people that supersaturation and calcium

concentration can be decreased by increasing the pH and [CO3]. It seems as unlikely as the observable reality that calcium can be removed from water by adding calcium to water through the addition of lime/ soda in common water softening applications. In a nutshell, non-equilibrium thermodynamics is neither intuitively obvious nor self-evident… It just is! This explains why hobbyists growing hard corals, who have the same supersaturation problem, don’t use strong bases like Na2CO3 or NaOH to increase their pH. Instead they use NaHCO3 (baking soda). This doesn’t directly increase the pH significantly, but it does increase the alkalinity. After mixing in baking soda, the mix is aerated to remove excess CO2 and slowly increase the pH to the desired level without creating a nucleation event, which would defeat your pH adjustment trying to get higher supersaturation.

Apparently the mystery story of the oyster hatcheries has a happy ending now that they learned a lot about carbonate chemistry the hard way. Nonetheless, they still have some issues with this low DO, high CO2 water. In areas where this water is created, the bottom is fully anaerobic, and some of the chemical byproducts created by these anaerobic conditions may still be present. This is what aquaculture deals with when we do anaerobic denitrification. Oyster hatcheries may have to add an aerobic biological treatment step to their input water supply, along with increasing Ω by increasing the pH and shifting bicarbonate to carbonate. This whole story probably explains a lot of why we don’t have near zero discharge, bio-secure, recycle oyster hatcheries. Almost all of the attempts to culture shellfish in high intensity recycle systems don’t even mention Ω. In an RAS shellfish

system, calculating Ω will not be as easy and will require actual calcium measurements, while the organic acids that build up will impact carbonate concentration and activity coefficient calculations and total alkalinity vs. carbonate alkalinity relationships.

Dallas Weaver, PhD, started designing and building closed aquaculture systems in 1973 and worked for several engineering/consulting companies in the fields of air pollution, liquid wastes, and solid wastes until 1980. Today, he’s the Owner/President of Scientific Hatcheries. e-mail:

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Canadian salmon and trout culture: status and opportunities

Canada has both the longest marine coastline and the largest number of

freshwater lakes of any country in the world. The country’s aquaculture By Asbjørn Bergheim*


recent report from The Senate Committee on Fisheries and Oceans (June 2016) indicates that the country has a diversified aquaculture industry, a rigorous regulatory regime and high-class aquaculture related research. In a global context, the annually produced volume is modest, ranked 21st.. Unlike leading salmon producers in Europe, Norway and Scotland, the growth of the annual production in Canada was only 0.4 % during 2003-2013. Nev-

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is primarily based on production of salmonids and shellfish.

ertheless, Canada could more than double its production within ten years (2014-2024) from 173,000 to over 378,000 tons including finfish and shellfish according to updated estimates. Atlantic salmon is the predominant species produced accounting for some 85 % of the total finfish production (Figure 1), while trout and steelhead represent a total of c. 8,000 MT/year. Coho salmon is reported to be produced in a few closed containment farms in Brit-

ish Columbia (BC), but the species constitutes a small part of the total volume. An overwhelming part of the salmon production takes place in open cages. Along parts of the western coast and in the eastern straits of Vancouver Island, BC there is a high density of cage farms and several hatcheries. In the Atlantic Region, New Brunswick and Nova Scotia are the biggest salmon culture provinces (Figure 2). Rainbow trout and brook trout are the most common species produced in freshwater. Ontario provides more than half of the amount, growing fingerlings in hatcheries situated in the south-west, while the grow-out sites are mainly located in the northern part of the province in the waters of Georgian Bay – North Channel of Lake Huron (Fisheries and Oceans Canada). Other main trout farming provinces are Quebec and Saskatchewan. British Columbia is the only province producing steelhead trout in seawater according to statistics (approx. 10 % of total trout volume). Canada is well reputed for its comprehensive research and development activity within aquaculture.

LEGEND Scallops Oysters Mussels Education Research Facilities Atlantic Salmon Marine Plants Provincial Capital

Figure 2. Salmon and shellfish farm sites on the coast of four provinces in the Atlantic region (Source: Atlantic Canada Opportunities Agency)

In a recent review (Canadian Aquaculture R&D Review 2015), a great number of current projects describe vital topics such as a development program for broodstock selection of Atlantic salmon, introduction of plant-protein based diets, occurrence and reasons for deformities in salmon production, etc. Ecological consequences of aquaculture including escapes of salmon from cage farms, interaction and hybridization between farmed and wild salmon (Figure 3), and nitrogenous waste from Chinook salmon are focused issues.

Sampling Location Fish Farm

The Broughton Archipelago area showing the locations of fish farms and the sites sampled during the 2012 monitoring program.

Figure 4. Sampling program studying distribution of sea lice from salmon cage farms in British Columbia (Courtesy: Peter Chandler)

Except for rainbow trout, the production of freshwater salmonid species is modest. Potential aquaculture species are Arctic charr and brook trout, and the project review also includes performed studies on feed optimization (e.g. inclusion of dietary plant protein) and genetic selection. Rainbow trout has been subject to numerous studies for more than 50 years in order to improve the performance under culture conditions – not least, Canadian research institutes have contributed a lot to the progress. As an example, the nutrition research at the University of Guelph has provided the industry with many important findings. How to cope with the sea lice problem is obviously a focus of concern in waters along both the Pacific and Atlantic coasts. An interesting project performed in the Broughton Archipelago (BC, 20122014) developed a predictive model of distribution of sea lice from the fish farms and estimated the number of encounters of migrating salmon with sea lice (Peter Chandler, pers. comm., see Figure 4.) In this region, lice infestations of migrating juvenile pink and chum salmon from freshwater to sea have been annually recorded since 2001. The spread of sea lice from farmed salmon probably contributes to the decline of some native Pacific salmon populations (The Ecological Society of America). So-called Bay Management Areas (BMAs) have been established in several Canadian jurisdictions with the precise aim of preventing impacts of disease and parasites (Senate Committee, op. cit.). BMAs designate minimum distances between aquaculture sites and identify zones where the producers must synchronize their operations (stocking, harvesting, fallowing). The production of salmon in Canada is said to be very healthy

At present, the production of

salmon in Canada is said to be very healthy. Over the last years, no harmful disease outbreaks of ISA and IHN have occurred.

Figure 3. Escaped farmed Atlantic salmon caught in Garnish River, Newfoundland (Photo: Chris Hendry)

and the average loss in the growout stage is about 10 %. Over the last years, no harmful disease outbreaks of ISA and IHN have occurred. The present vaccination of all Atlantic salmon obviously prevents outbreaks of diseases that caused losses at some farm sites 1015 years ago.

Dr. AsbjØrn Bergheim is a senior researcher in the Dept. of Marine Environment at the International Research Institute of Stavanger. His fields of interest within aquaculture are primarily water quality vs. technology and management in tanks, cages and ponds, among others.

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THE Shellfish CORNER

Oyster Shells, Cultching, and Oyster Farming By Michael A. Rice*

I recently read with interest an article in the Connecticut Sea Grant publication Wrack Lines (Spring-Summer 2016) by Tim Macklin about their effort in Fairfield, Connecticut to collect oyster shells from local restaurants. The goal is to place the shells onto local recreational shellfishing beds in an effort to enhance the oyster set. Tim and his colleagues on the Fairfield Shellfish Commission are acting locally, but they have been following in the footsteps of a fellow Connecticut Yankee, John Volk, who was the chief of the Connecticut Bureau of Aquaculture in the state’s Department of Agriculture.


olk, like many professionals familiar with the oyster farming business, recognized that healthy setting substrate or cultch on seed beds is critical for healthy oyster settlement and seed production. And this has been known by practitioners for a very long time. For example, one of the first treatises on oyster culture available in America was the 1883 translation of University of Kiel Professor Karl Möbius’s 1877 Die Auster und de Austernwirschaft (The Oyster and Oyster Culture), translated and published as a 65-page appendix in the 1880 United States Commission of Fish and Fisheries — Report of the Commissioner. This treatise is remarkable in that it was the first description of what Möbius termed as ‘biocenose’ for the interaction of organisms on the oyster beds, or what we now more commonly know as community ecology today. Möbius clearly outlined the importance of having oyster shells as a proper setting substrate for the continued artificial propagation of oysters. But even before this scientific literature reached American shores, there 64 »

had been an appreciation for the value of oyster shells as being important for continued healthy shellfish beds. For example in my home state of Rhode Island, there was a public law passed during the January 1852 legislative session Amendment to the Act entitled ‘An Act for the Preservation of Oysters and other Shell Fish within this State’ that reads as follows: SECTION 6. All persons taking oysters from any bed in the free and common oyster fisheries within the waters of this State, shall at the time of such taking, cull and restore to said bed all small oysters, shells, stones, and other substances valuable to said bed, retaining only such oysters that are fit for market and present use. It is clear that with this legislative language that there was a good degree of understanding about the value of shell as somehow valuable for the continued well-being of the oyster grounds. Of course, as time has gone forward our understanding of the value of oyster shells as cultch material has become better refined. For example, this concept has been refined by Dr. Thomas M. Soniat of

the University of New Orleans and several of his co-workers to the point that oyster shell budget modeling can be used as a means for predicting sustainable oyster harvests from public beds and predicting the best areas for oyster habitat restoration projects [see Journal of Shellfish Research (2014) 33:381-394]. In the spring of 1986, Volk managed to find $20,000 USD left over in the Agriculture Department’s budget, and he used those funds to purchase 20,000 bushels (28.378 bu/m3) of clean oyster shells to be used as cultch or setting substrate for oysters on seed beds. Working with private aquaculture firms, they then spread the shell onto 20 acres (0.404686 ha/acre) of cleaned bottom on Long Island Sound that had a known history of good oyster sets. That experiment went well, and later that fall Volk went to the state legislature to ask for enough money to revitalize all of their 3,000 acres of state oyster seed beds in the Sound. Despite considerable skepticism by notoriously frugal legislators, Volk appealed for funds by using an argument for jobs and economic development,

Advertisement of the H.C. Rowe Oyster Company of Fair Haven, CT from the 1880s (Original in Connecticut Historical Society collections)

Starfish mop on Connecticut oyster boat 1940s (Photo Courtesy of NOAA Fisheries)

and as a result his bureau was appropriated $1.3 million USD. And later the next year, another $4 million USD state bond initiative was used to buy about 5 million bushels of clean oyster shell for the project. Starting in the spring of 1987, the state and the private oyster companies cleaned the seed beds in the Sound and laid down the cultch at about 1,700 bushels per acre using fire hoses

to hydraulically push out shells heaped onto barges. Luckily during that summer of 1987 the temperatures were right, and that fall a bumper crop of seed oysters were sold for transplant out to growout beds in deeper waters using Connecticut’s traditional onbottom culture methods. The results of Volk’s cultching efforts were very successful from the standpoint of economic return. The wholesale value of Connecticut’s oyster harvest nearly doubled to $9 million in 1988, and by 1991the wholesale value of the oyster harvest reached $33.3 million USD and subsequently $50 million USD in 1993. The plan to make the cultch program economically sustainable was through a 10 % tax on oyster seed sales that would be directed back to the Aquaculture Bureau for continuation of this cultching program. Unfortunately beginning in 1998 and extending into the early 2000s there were two oyster disease (‘Dermo’ Perkisus marinus and “MSX’ Haplosporidium nelsoni) outbreaks that severely impacted oyster harvests in Connecti-

Leased oyster grounds in Bridgeport and Stratford Connecticut in 1889 (Originals in Connecticut State Archives, courtesy of G.W. Blunt White Library, Mystic Seaport)

cut and dampened the enthusiasm for the formal mechanism set in place to institutionalize the funding of cultching program on Connecticut’s publicly-held seed beds. Declining oyster production was noticed by the legislature, so the 10 % tax on seed sales was eliminated in 2004 in a general effort to reduce state taxes. This is a sad example of how the long-term thinking required for investing in the growth of agricultural systems is frequently a foreign concept when the cycles of realpolitik and state budget priorities run for just two years. The farmgate value of Connecticut’s commercial oyster harvest has settled in to around $15 million USD in recent years and the Aquaculture Bureau remains determined to educate their political leaders about longterm investments. Connecticut has a long history of success in the publicprivate partnership in the Long Island Sound oyster farming enterprise and there is no reason why it should not be a continued success [for more information see: Zachary, C. & M. Arnold 2015. Against the tide Connecticut oystering, hybrid property, and survival of the commons. Yale Law Journal 124:8821345]. Aquaculture industry growth in coastal waters that are held in the public trust involves constant renewal, cooperation and education of the decision makers about long-term priorities, and the industry itself must be an important player in this process.

Michael A. Rice, PhD, is a Professor of Fisheries, Animal and Veterinary Science at the University of Rhode Island. He has published extensively in the areas of physiological ecology of mollusks, shellfishery management, molluscan aquaculture, and aquaculture in international development. He has served as Chairperson of his department at the University of Rhode Island, and as an elected member of the Rhode Island House of Representatives.

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Fish Centric Aquaponics.

The Right Tool for the Right Job. By: George B. Brooks, Jr. Ph.D.

In my opinion, aquaponics has gotten a bad rap.


t sounds like this: “I like aquaponics and many of my best friends are aquapons. I would never say anything bad about their hobby, or impede their enjoyment, and I love the tomatoes they produce. But aquaponics will not provide much help for the seafood crisis nor with the growing animal protein need the world faces.” Such remarks appear to relegate this comparatively new technology to forever be a “pastime,” a toy that some play with in their backyards, never to take part in addressing the real food needs of the world. The problem is that to some degree those who hold this opinion are correct. This fledgling ag-technology based industry has focused far more on plant production than on the fish. This is a good course of action for many. Fish can be challenging from management, sales and regulatory standpoints. To fully clean the water for the fish requires the production of far more plant biomass than fish, so plants make up the majority of aquaponic product. Messing with the fish populations can dramatically affect nutrient levels, in turn negatively affecting plant growth, so why do that? Also from a sheer vegan/moral perspective, many people do not 66 »

eat meat or wish to kill animals and there is nothing wrong with that. I suggest though, that by not focusing on fish/seafood production as much as on vegetables and fruit, aquaponics is missing a major opportunity to benefit the world. Nine billion people will need to eat. For some products we may forever be dependent upon large-scale agriculture technologies. If the rains do not shift from the Great Plains of the U.S. thanks to climate change, the world will continue to need them to

produce corn and wheat. In a similar manner the world will continue to need the millions of tons of fish produced by deep sea sustainable fisheries, by the great catfish farms of the southern U.S., the ocean based cage farms and the land based farms for tilapia, shrimp and other species that are found across the globe. However, there is also the growing need and desire for urban agriculture and its solutions to so many problems including reducing foodmiles, enhancing food security, cre-

ating local jobs and mitigating food deserts. This is where aquaponics fits in where thousands of acres of ponds don’t. My own story fits in here as well. I came to aquaponics as a fish producer. I had always wanted to grow fish in the city but could not because the cost of building and operating traditional recirculating aquaculture systems was too much and they wasted too much water. Aquaponics provided the solution that I needed. The addition of grow beds for plants to a traditional RAS (recirculating aquaculture system) created a second profit center and polished the water removing the nitrate that would eventually build up in traditional RAS. Though some believe otherwise, designing new aquaponic systems that emphasize improved fish culture at both the commercial and artisanal (back yard) scales is possible. Although traditional aquaponics is focused on plants, in other parts of the world with more fish based societies, aquaponics is logically more fish centered. One of the techniques that have caught the attention of the UN for ease of use and lower costs is called Bumina and Yumina. Translated as “fruit–fish” and “vegetable– fish,” it consists of a simple fish pond from where water is pumped through a clarifier and then gravity fed through small containers, providing aeration as it cascades back into the pond. A simple and effective technique to say the least. More traditional aquaponics practitioners may feel that “Bumina and Yumina” wastes good plant grow space. But for those who practice this method the fish are more important for the high quality protein they provide. Fish centric methods that better fit traditional sensibilities and that are socially, economically, and environmentally viable in a wide variety of circumstances can also be developed with a little innovation. There are two last issues I’d like to briefly discuss. First, as part of a

fish centric aquaponics philosophy, just as has been done with plants, much more work needs to be done to develop a wider variety of acceptable and potentially profitable species. Tilapia is the fish of choice at the moment because it is easy to handle and can be of very good quality. It is also invasive and many states and some nations have restrictions on it. Channel and blue catfish are also well domesticated and cold tolerant but fingerlings can be difficult to get depending on where you are. Macrobrachium (freshwater prawns) and Redclaw crayfish can do well in a DWC (Deep Water Culture) grow bed but the prawns are territorial and cannibalistic and some consider the Redclaws invasive. Bluegills and other centrarchids can work and taste great but are slow growing. Intuitively Barramundi cannot reproduce in the wild in most of the United States. But after the invasion of the Asian bighead carp, many Game and Fish departments may not be willing to take the chance. Asian catfish species including patin and Pangasius (Basa) show international potential. The list goes on but clearly with focused research to address issues like these, the opportunity for a wider species pallet is there. Finally at least for this commentary, there is the concern that beyond personal use, fish from aquaponics can be difficult to sell. At least for the moment, it seems that this issue may be a bit overrated. Where lack of market is in question, anecdotal evidence suggests that it is a perceived regulatory challenge. In preparation for this article a quick check of the ability to sell fish at U.S. farmers markets revealed a hodgepodge of different rules and laws across the country. But more often than not a backyard farmer could actually sell their fish without too much difficulty. Interestingly none of the rules I found mentioned personal aquaculture as a source of product but they did mention artisanal fishermen. For

instance the following is a statement that governs fish sales at New York farmers markets, “No permit, license or certificate is required if a freshwater fisherman is selling only whole, non-protected species.” It therefore would only be a very small leap to move from freshwater fisherman to freshwater fish farmer. Naturally nothing is ever that easy but the issue deserves attention. There is an old saying. “The right tool for the right job.” A tool is an appliance designed to accomplish a task or solve a problem. A hammer is a tool. Applied to the wrong task it can cause destruction. Conversely, pressed to the right job it can help to create masterworks of art. Aquaponics is no different. If applied to the wrong purpose or with inappropriate expectations, it may never reach its potential. But applied to the right cause, there is no telling what may be achieved. Everybody is a Genius. But If You Judge a Fish by Its Ability to Climb a Tree, It Will Live Its Whole Life Believing that It is Stupid - Albert Einstein

*Dr. George Brooks, Jr. holds a Ph.D. in Wildlife and Fisheries Sciences from the University of Arizona in Tucson and served as that institution’s first Aquaculture Extension Specialist. He is currently Principle at the NxT Horizon Consulting group and also teaches Aquaponics at Mesa Community College. Dr. Brooks is co-chairing the upcoming Aquaponics Association conference in Austin Texas. He may be reached at

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The Fishmonger

Taking Control

of the Agenda Industry apathy has led to outside organisations setting the seafood industry agenda for some time


ur industry has a passionate and resilient core but generally speaking the impression we give is that we would rather be somewhere else rather than confronting issues. It is regularly stated that when successful companies face big changes in their environment, they often fail to 68 »

respond effectively. Many feel unable to defend themselves against NGO groups with new technologies and/ or strategies, and they watch their sales and profits erode, their best people leave, and their stock valuations fall. Some ultimately manage to recover— usually after painful acts of restructuring—but many don’t.

One report recently said: “It’s often assumed that the problem is paralysis. Confronted with a disruption in business conditions, companies freeze; they’re caught like the proverbial deer in the headlights.” That explanation doesn’t always apply though as on many occasions the issue is not an inability to take action but an inability to take appropriate action. Of course, there can be many reasons for the problem—ranging from managerial stubbornness to sheer incompetence/ignorance —but one of the most common is inertia. Inertia (or apathy) is an organization’s tendency to follow established patterns of behavior—even in response to dramatic environmental shifts. Stuck in the thinking and working of the past that brought success, they simply accelerate all their tried-andtrue activities and all they end up doing is digging a bigger hole to get out of. The seafood industry, despite the incredible innovation that we see on a regular basis from individual people and organisations, collectively tends to be confronted about a problem – retreats and digs that hole. It will often retreat to that hole and protect itself from the trench. Seafood fraud and illegal, unregulated and unreported (IUU) seafood are two such issues. We, the seafood industry, could have a serious impact on these if we chose to take some leadership. The first requirement is to recognize the issues that will impact on our most important asset – our customers. Unfortunately outsiders put the problems in the public space and they have been setting the agendas so we constantly have to put out ‘fires’ rather than us being recognized as the major catalyst for stamping out these bad practices. There are no gray areas when it comes to business today – transparency is a must and anything less will be seen more and more as covering up shady deals. That being the case we need to try and take the agenda back.

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The Fishmonger

The Fishmonger recently saw a University of Washington study which broadly examined the ecological and financial impacts of seafood mislabeling. The headline from this was ‘Mislabeled seafood may be more sustainable.’ Warning bells were ringing. One of the comments in the report states that ‘in most cases, mislabeling actually leads to people eating more sustainably, because the substituted fish is often more plentiful and of a better conservation status than the fish on the label.’

Quoting from the report: • The study didn’t examine the potential reasons behind this, but the researchers speculate that while it could be intentional mislabeling to rip off consumers, it is just as likely restaurants and markets are serving and stocking fish they think match the label, but are cheaper, more plentiful options. A white-fish filet can look like any number of species, they explained, and substitutions could happen anywhere in the supply chain. • The new study also summarizes which fish are most likely to be mislabeled and, of those, which varied the most in conservation status between true fish and mislabeled fish. For example, snapper is one of the most frequently mislabeled fish. Its conservation status is vulnerable to endangered — meaning its population isn’t doing well — but the fishes most often sub70 »

stituted for snapper aren’t considered critically endangered. • Results from this study could be useful in helping consumers make sustainable purchasing decisions by avoiding fish that are most likely to be mislabeled. That list is led by croakers, shark catfish (or “basa”), sturgeon and perch. Consumers can also look out for fish commonly replaced with species that are not from sustainable stocks. Examples include eel, hake and snapper. • These results could also help seafood certification groups focus efforts on fisheries that are most likely to be mislabeled, the researchers say. A fish often travels from the port to processors and several distributors before reaching the end market, and this change of hands is likely where mislabeling happens, the new study found. Can you see where this is heading if we allow this to continue? It is definitely time to grab this agenda and get the industry focused on one name – one fish as successfully achieved in the Australia Fish Name Standard AS 5300 SSA ( Pages/default.aspx ). This could become the keystone to a global standard. Additionally the EU’s new fish and aquaculture consumer labels came into force a few years back (https:// consumer-information_en ) where

they established that specific information must accompany fishery and aquaculture products sold to consumers and mass caterers. These requirements complement the general EU rules on the provision of food information to consumers, and contribute to more transparency on the market as they enable consumers to make informed choices on the products they buy.

Under these rules, applicable to fish, molluscs, crustaceans and algae, products sold to consumers or mass caterers must bear the following information: • the commercial and scientific name of the species • whether the product was caught at sea or in freshwater, or farmed • the catch or production area and the type of fishing gear used to catch the product • whether the product has been defrosted and the date of minimum durability (also known as the ‘best before’ or ‘use by’ date), in line with general food labeling rules To allow consumers to have a better understanding of where the product comes from, the information on the catch or production area must be provided in detail: • For fish caught at sea: - In the Northeast Atlantic, Mediterranean and Black Sea: the name of

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The Fishmonger

the FAO sub-area or division as well as a simplification for the consumer (a clearer name, a map or a pictogram) - In other waters: the name of the FAO area • For freshwater fish: the body of water and the EU country of origin or the non-EU country of provenance • For farmed fish: EU or non-EU country of final rearing period EU regulations also state that products may also be accompanied by additional voluntary information, such as the date of catch or landing, information on environmental, social or ethical matters, production techniques and nutritional content. Towards the end of last year FAO published the ‘HANDBOOK ON FOOD LABELLING TO PROTECT CONSUMERS.’ This highlights that at the Second International Conference on Nutrition (ICN2), held in Rome 19-21 November 2014, governments (including USA) affirmed that “empowerment of consumers is necessary through improved and evidence-based health and nutrition information and education to make informed choices regarding consumption of food products for healthy dietary practices” (FAO/WHO, 2014a). Food labeling was included among the recommendations in the ICN2 Framework for Action (FAO/WHO, 2014b). The booklet states that food labeling has been recognized as an effec-

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tive tool to protect consumer health in terms of food safety and to promote nutritional well-being. Labeling laws prevent fraud and misleading information which protects consumers as well. Food labels have traditionally been used to convey information about the product identity and contents, as well as providing information about how to handle and prepare the food product safely. In recent decades, food labels have become vehicles to inform consumers about the relationships between specific food products and health. The Handbook offers a brief introduction to labeling as part of an ongoing effort to assist regulators and others working in the food system that are responsible for formulating and implementing food labeling policies. This includes the reasons for food labeling and general principles and best practices that apply to all labels. Brief explanations about specific types of label information are provided, such as ingredient lists (including allergen and food additive information), date marking, nutrition labels (back of pack panels and front of pack systems) as well as nutrient and health claims. Legal and trade considerations are highlighted as well. Many sections of the book are based on the guidance given by the Codex Alimentarius Commission on food labeling in particular the Codex General Standard for the Labeling of

Prepackaged Foods (CODEX STAN 1-1985). This book provides a framework for understanding the reasons for food labels and practical advice for developing food labeling policies. Once the reader is aware of the technical, legal and economic aspects of developing specific label information, they will undoubtedly need additional information before formulating their policy. This book provides readers with sources of information about real world examples of the processes for implementing labeling policies. With these tools/resources The Fishmonger believes that the industry has everything it needs to drive this transparency throughout the industry and show the leadership that not only good honest operators expect but also what consumers deserve. It is a fact that if you drive confusion from the process you will definitely increase consumer confidence and that will result in improved seafood consumption. Industry often speaks about a ‘level playing field’ between imports and domestic production and clearly a tighter control on fish names and traceability will not only do that but will also assist authorities to tidy up IUU matters. Let us work together to get this agenda moving! The Fishmonger

» 73

The Long View

The Third Rail We live on a finite planet. Food production has the greatest negative By Aaron A. McNevin*


here are natural resources that can be used for the benefit of humans, and the production of food, but if we use those resources beyond their ability to replenish, we begin to deplete our natural resource base. In essence, we would be spending down our principal – the result being that our output of natural resources that could be used for human benefit would decrease. Thus, it is imperative that we maintain our resource base within sustaining limits (Fig. 1). At a fundamental level, the number of people and the rate at which we use resources should equal some renewable limit of resources on the planet. Unfortunately, humans are using resources beyond what the Earth can sustain. If there is any question, recall how many times you

impact on the environment. However, humans require food.

have said or heard that aquaculture is essential because we are overfishing the oceans. Humans can improve the efficiency of food production, we can improve the efficiency of how we use food or humans can reduce their numbers on the planet. There is a succession in how these changes occur. When resources are finite, the first tendency is to use these resources to produce food as efficiently as possible. This intervention is outward and doesn’t involve a behavioral change for humans, rather modifications to food production practices. When we have optimized production practices to maximize food output but continue to require more food, the rate of food use changes. This intervention requires humans to behave differently, i.e. waste less food and con-

Figure 1. Depiction of renewable natural resources being extracted at different rates over time.

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sume less food. When production output has been maximized, human use of food is optimized and there is still a need for greater food output, humans will seek means to reduce their numbers. The most common means for population reduction is war as food and water scarcity influence political stability and often result in conflict. While there have been some attempts to proactively reduce human numbers such as mass sterilization in India or China’s one child policy, much of the world has abandoned any effort to maintain a certain population number because of the unintended consequences and human rights violations that result from these interventions. Production methodologies will change, more efficient crops will be produced and food production will generally move towards greater efficiency. The rate at which these changes are made to improve efficiency is variable. However, and there will be an extent to which production efficiencies can improve resource use for food production. Reducing food consumption has not been a large platform for many of the NGOs engaged in the aquaculture sector. This is likely because the private sector, including seafood buyers, are seen as leverage to change poor food production practices and environmentalists have made corporate engagement one of their biggest bets. A decrease in food consump-

Figure 2. Simplified schematic of how food items may be evaluated to determine environmental impact.

tion would result in decreased food sales throughout the supply chain. The communistic lens that decreased consumption is seen through, coupled with the likely slowdown in per capita food sales, makes food consumption a third rail discussion topic. But should it be? An environmental advocacy group tells you not to eat as much shrimp because the environmental burdens are great. Your doctor tells you to reduce shrimp consumption because your cholesterol is too high. The doctor is seen as looking out for your best interest but how is the NGO viewed? Perhaps one approach to having a more candid discussion on food consumption is to first address food waste? The environmental issues associated with food waste are the same as the environmental issues related to over-consumption. Consider the following two scenarios â&#x20AC;&#x201C; (1) a tilapia fillet is left too long in the refrigerator and is discarded; (2) a person that has already consumed the daily protein requirements consumes an additional tilapia fillet. The natural resources used to produce the tilapia fillet in the first instance were wasted, but can the tilapia fillet

consumption in excess of the daily protein requirement be viewed in the same manner? A tilapia fillet, though, is not the same as a salmon fillet. Moreover, a tilapia fillet is not the same as a ribeye steak. In many cases aquaculture is more efficient at producing protein than other types of animal husbandry. Thus, there are likely less impactful types of foods than others and consumption probably should increase in those areas and decrease in the high-impact products. The analysis of which foods are better than others from an environmental perspective requires a systematic approach for evaluation (Fig. 3). This evaluation has to not only take into account the efficient use of resources, but also the localized impacts on biodiversity. Further, the analysis must weigh these factors among aquaculture species and also within different production system types (cage, pond, RAS, etc.). These analyses for aquaculture species and systems then need to be compared with those systems and species associated with other types of protein. Food consumption is simply part of an equation that impacts our

health and our environment. It is a rate and this rate can be manipulated, not only numerically, but also in the type of food consumed. Adjusting this rate and the type of food consumed can impact the environment, human health, economics and development. An issue that can touch all of these important global topics seems to be one that should be discussed in a more open context.

Dr. Aaron McNevin directs the aquaculture program at the World Wildlife Fund (WWF). He received his MS and PhD from Auburn University in Water and Aquatic Soil Chemistry. Aaron has lived and worked in Indonesia, Thailand and Madagascar and currently manages various projects throughout the developing world. He previously worked as a professor of fisheries science, and is the co-author of the book Aquaculture, Resource Use, and the Environment.

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Perspective and Opinion


with Dr. Claude E. Boyd AQM: Could you give us a brief history of how you got involved in the aquaculture industry? CB: As a college student, I initially wanted to study geology – specifically geochemistry. But, that was in the 1950s, and oil was plentiful and cheap. The Geology Department at Mississippi State University advised me not to study geology, because there was no demand for their graduates. Times have certainly changed. Anyway, I studied biology and chemistry as a double major and then got a master’s degree in insect toxicology. Afterwards, I went to Auburn University to pursue a doctorate under Dr. J. M. Lawrence who was working with aquatic herbicides. He had a project requiring chemical analyses of water and aquatic plants. Because of my chemistry background, these analyses became my responsibility and some of the work became the topic of my dissertation. Following graduation, I accepted a postdoc in ecology under Dr. E. P. Odum of the University of Georgia. I learned a lot about the relationship between chemistry and ecology, but I was not satisfied with conducting basic studies for which I saw no practical application. Dr. H. S. Swingle at Auburn University told me that water quality would be a limiting factor in the future of aquaculture and that aquaculture had the potential to become a huge industry. He allowed me to return to Auburn University as a researcher on pond water quality. This turned out to be “a good fit” for 76 »

Claude E. Boyd.

me, and I have continued the effort until today.

AQM: What are some of the ups and downs of the industry itself over the years that stand out in your mind? CB: Aquaculture has its ups and downs, but the ups have far exceeded the downs. Global aquaculture production has increased from less than 1 million metric tons in 1960 to 73.8 million metric tons in 2014. There also has been an increase in production intensity. To illustrate, in

the 1970s, shrimp production seldom exceeded 2,000 kg/ha/crop. Today, 6,000 to 8,000 kg/ha/crop is relatively common, and with biofloc technology, over 15,000 kg/ha/crop is not uncommon. Intensification was possible mainly because of better feeds and mechanical aeration. There are nonetheless several continuing problems facing aquaculture producers. As in all types of agriculture, there is a need to increase production for the future demand. However, at any given time, producers have tended to overproduce. This

is good for consumers, because it has tended to assure a relatively low price. But, it limits profits for the producer. Greater intensification also has resulted in greater feed input and water quality deterioration. A higher density of animals and impaired water quality result in stress and more problems with disease. The interaction of feed input, water quality, aeration rate, and disease deserves more attention. The expansion and intensification of aquaculture also has led to concerns over the long-term, ecological sustainability of aquaculture.

AQM: What are your views in general about aquaculture throughout the world: what works, what doesn’t? CB: Aquaculture must become more efficient – especially at the farm level. This will require application of the methods of production that have been proven efficient. Unfortunately, producers seem to trust their judgement or the advice of their friends and neighbors more than aquaculture science. Some examples will be provided: • Fish farmers often do not apply enough mechanical aeration for maintaining adequate water quality in ponds in spite of much effort to convince them to use more aeration. • Overfeeding results in wasted resources, water quality deterioration, and higher production costs. Nevertheless, overfeeding and higher than necessary feed conversion ratios are common in commercial aquaculture. • Many studies have shown that fish meal in diets for most aquaculture species can be replaced with plant meals and animal by-product meals. Nevertheless, this information has not been adopted widely by feed manufacturers and farmers. • In Asia, farmers continue to use highly inefficient aerators. Efficient aerator designs used in US aquaculture have not been adopted in Asia despite numerous effort to introduce this technology.

• I believe that the understanding of water quality principles is almost non-existent among commercial producers. Among professional aquaculturists, few have more than a superficial understanding of water quality. Considering the importance of water quality – especially in intensive aquaculture – more effort should be made to disseminate water quality information.

AQM: What are some things industry, academicians, policy makers, and support industries should be preparing for in the coming decades? CB: One of the major constraints to future expansion of aquaculture is the availability of fish meal and oil. Aquaculture presently uses about 60 % of the global fish meal supply and around 80 % of the global fish oil supply. These statistics suggest that global aquaculture production could be restricted by a shortage of fish meal and oil in the future. Effects of aquaculture on the environment tend to be localized, but in some areas, aquaculture is the major activity. In such places, aquaculture may be the main source of water pollution and of negative impacts to both terrestrial and aquatic biodiversity. Aquaculture, like other industries, should be required to improve its environmental stewardship. Many countries do not have effective environmental protection programs, and this has led to the formation of several aquaculture eco-label certification programs. Such programs can result in improved environmental stewardship at participating farms, nearly all of which produce for export to the United States, European countries, and other developed countries. The majority of aquaculture is for domestic markets in Asian countries where certification provides no market advantage. An effort must be made to improve environmental stewardship by producers not seeking eco-label certification status.

Dr Boyd with Auburn Dean Dennis Rouse.

The public knows little about aquaculture, and this includes the wider scientific community. My colleagues in other disciplines at Auburn University think that I spent my career studying the best way to catch sportfish. Why, I do not even like to sportfish, I had much rather play golf or smoke a cigar. The point is, the industry has done a very poor job of explaining to the public its methods, its products, and its importance to society. If aquaculture was understood better by the public, politicians, and policy makers, it could greatly improve its image and afford a better opportunity of receiving support from the public, governments, and international agencies. The training of aquaculturists at the undergraduate level, at least in the United States, in my opinion, is quite deficient. Aquaculture is a complex endeavor that requires knowledge from a variety of fields. Nevertheless, most undergraduate aquaculture students focus on aquatic biology and receive little training in the physical sciences, agriculture, management, etc. Of course, there is a limit on how much coursework students can take, but more quantitative-type classes could be greatly beneficial. Graduate training has become far too specialized. Many of the doctoral students in aquaculture focus on a single aspect of aquaculture and learn very » 77

Perspective and Opinion

little about production aquaculture. There also seems to be a danger of an almost complete departure from practical research in aquaculture. This seems to be driven by the increasingly prevalent notion that the only research worth publishing is from the investigation of novel topics. This notion is silly – might as well say it – plain stupid. Often, a finding that is novel must be examined in subsequent research before it can be verified. Also, research can be novel yet completely frivolous and of no benefit to the advancement of useful knowledge or practice. In aquaculture, findings should have practical use or provide knowledge that has the possibility of leading to something practical. Aquaculture is not a basic science; it is a method of food production and a business. Some of my comments are quite negative, but I am neither bitter nor a curmudgeon. I really feel that humans have a remarkable ability to succeed in the face of all obstacles. Nature presents many problems, we create even more problems, and we tend to be selfish and uncooperative, but in the long run humans have an uncanny capacity to work together enough to survive and progress. Aquaculture is essential to the global food supply, and I truly believe that it will satisfy that role in the future.

AQM: What advice would you give to recent graduates considering a career in aquaculture? CB: Recent graduates in aquaculture must work in a more competitive en-

vironment than I did. When I began my efforts in water quality, there were few other researchers doing similar work. Today, there is greater interest in aquaculture water quality and more researchers. This is even truer in other more popular areas such as nutrition, genetics, and aquatic animal health. But, there is still much to discover that could improve the efficiency of aquaculture. However, the design of meaningful experiments is more difficult than in the early days, because many of the obvious experiments have been conducted. I believe that the researcher should obtain a good understanding of the real problems encountered in commercial aquaculture and isolate an important problem for study. The nature and cause of the problem is important, and it needs to be described and its cause elucidated. But, this may take longer than it does to find a practical solution. Thus, while studying the problem, one should also be seeking a workable solution even though all of the details about the nature and cause of the problem have yet not been elucidated – and possibly never will be. Many aquaculture graduates will work directly in the industry rather than being researchers. For these, all I can offer is that the better you understand the principles of aquaculture production or of the particular aspect of aquaculture with which you are involved, the better you will do your job. You should continue to study and learn for the rest of your life. Work can be very interesting and fulfilling – more fun than recreation.

AQM: And, finally, what advice would you give to someone starting an aquaculture business? CB: I am not a business person, because I do not like to take more risks than I incur just by living. There is no way I would borrow a lot of money and gamble that I could pay it back and make a profit through commercial aquaculture. For this reason, I 78 »

Aquaculture is essential to the global food supply, and I truly believe that it will satisfy that role in the future.

chose to work for a salary – maybe I am just a financial coward! Anyone going into aquaculture as a business should be aware that it is agriculture and equally risky. Aquaculture can be profitable, but it will not be profitable every year. It will have its ups and downs, but for those willing to learn and apply proven management practices and make changes as better techniques evolve, it can be a good business. For those not willing to do this, aquaculture is a casino and there is an almost complete certainty that you will lose in the long run. You also need to understand your limitations. Some of us, like myself, are just not capable of being an effective manager. It takes a good manager to be successful in aquaculture, and the managing involves all aspects of the business not just the production of fish, shrimp, or other aquatic animals.

Dr. Claude E. Boyd earned a B.S. in Entomology and an M.S. in Insect Toxicology, both from Mississippi State University, and a Ph.D. in Water Quality at Auburn University. Recognized around the globe as an authoritative expert on water quality in aquaculture, Dr. Boyd has been an industry pioneer and leader for over 50 years. We hope his contributions and guidance will continue for many more years to come.

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aquaculture events

FEBRUARY Aquaculture America 2017 Feb. 19 – Feb. 22 San Antonio Marriott River Center. San Antonio, Texas, US T: +1 760 751 5005 E: W: WORLD OCEAN SUMMIT 2017 Feb. 22 – Feb. 24 Sofitel Bali Nusa Dua Beach Resort. Bali, Indonesia T: +852 2585 3312 E: W: MARCH OFFSHORE MARICULTURE 2017 Mar. 6 – Mar. 10 Hotel Coral & Marina Ensenada, Baja California, Mexico E: W:

International Conference on Marine Science and Aquaculture 2017 Mar. 14 - Mar. 15 The Magellan Sutera. Kota Kinabalu, Malaysia T: +60 883 20 000 E:

antibiotics, probiotics and FEED additives EVONIK Industries AG................................................................9 Contact: Cristian Fischl T: + 52 (55) 5483 1030 Fax: + 52 (55) 5483 1012 E-mail:, heliae.........................................................................................19 578 E Germann Road Gilbert, AZ 85297 T: (800) 998-6536 E-mail: Lallemand Animal Nutrition................................................49 Contact: Bernardo Ramírez DVM Basurto. Tel: (+52) 833 155 8096 E-mail: Reed Mariculture, Inc............................................................47 900 E Hamilton Ave, Suite 100. Campbell, CA 95008 USA. Contact: Lin T: 408 377 1065 F: 408 884 2322 E-mail: SKRETTING....................................................................................5 Skretting Ecuador - Km 4.5 & 6.5 Durán - Tambo. Durán - Ecuador. T: +593 4 2598100 + 593 4 2815737 E-mail: SYNDEL.......................................................................................45 CANADA T: 1 800 663 2282 USA T: 1 800 283 5292 Zeigler Bros, Inc..................................................Inside cover 400 Gardners, Station RD, Gardners, pa. 17324, USA. Contact: Susan Thompson T: 717 677 6181 E-mail: aeration equipment, PUMPS, FILTERS and measuring instruments ADVANCED AQUACULTURE SYSTEMS, INC..................................37 4509 Hickory Creek Lane, Brandon, FL 33511 Contact: Dana Kent T: (800) 994-7599 / (813) 653-2823v E-mail: Aqua Logic Inc..........................................................................27 9558 Camino Ruiz San Diego, CA 92126, USA. T: 858 292 4773 Aquatic Equipment and Design, Inc.....................................25 522 S. HUNT CLUB BLVD, #416, APOPKA, FL 32703 Contact: Amy Stone T: (407) 717-6174  E-mail:

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VIV ASIA 2017 Mar. 15 – Mar. 17 Bangkok International Trade & Exhibition Centre (BITEC). Bangkok, Thailand T: +66 2 670 0900 W: SEAFOOD EXPO NORTH AMERICA 2017 Mar. 19 – Mar. 21 Boston Convention and Exhibition Center. Boston, USA T: +1 207 842 5504 E:

SEAFOOD EXPO GLOBAL + SEAFOOD PROCESSING GLOBAL Abr. 25 – Abr. 27 Brussels Expo. Brussels, Belgium T: +1 207 842 5504 E: MAY AQUACULTURE SUMMIT 2017 May 25 – May 27 Osaka, Japan E: W:

GIANT PRAWN 2017 Mar. 20 – Mar. 24 Asian Institute of Technology Conference Centre. Bangkok, Thailand E:

JUNE SEAFOOD SUMMIT Jun. 5 – Jun. 7 The Westin. Seattle, EE.UU. E: W:

APRIL AquaME Abr. 10 – Abr. 12 Dubai International Exhibition and Conference Centre Dubai, United Arab Emirates T: +971 4 407 2606 E: W:

WORLD AQUACULTURE 2017 Jun. 26 – Jun. 30 Cape Town International Convention Centre. Cape Town, South Africa T: +1 760 751 5005 E: W:

advertisers Index

Fresh Flo..................................................................................13 3037 Weeden Creek Rd. Sheboygan, WI 53081 Contact: Barb Ziegelbauer T: 920-208-1500 E-mail: Integrated Aqua Systems, Inc..............................................61 2867 Progress Place, Suite E. Escondido, CA 92029. Contac: Christine McKay General Manager T: (800) 640.2148 Office: (760) 745.2201 Fax: (858) 408.2922 E-mail: OxyGuard International A/S.................................................31 Farum Gydevej 64, DK-3520 Farum, Denmark Contact: Jelena Kvetkovskaja T: +45 4582 2094 E-mail: Pentair Aquatic Eco-Systems, Inc......................back cover 2395 Apopka Blvd. Apopka, Florida, Zip Code 32703, USA. Contact: Ricardo Arias T: (407) 8863939, (407) 8864884 E-mail: / RK2 Systems...............................................................................7 421 A south Andreassen Drive Escondido California. Contact: Chris Krechter. T: 760 746 74 00 E-mail: Sun Asia Aeration Int´l Co., Ltd........................................29 15f, 7, Ssu-wei 4 road, Ling-ya District, Kaohsiung, 82047 Táiwan R.O.C. Contact: Ema Ma. T: 886 7537 0017, 886 7537 0016 E-mail: Valterra Products LLC.....................................................41 Mission Hills, CA Contact: Tera Grengs, Marketing Manager. T: 818-898-1671 x11 E-mail: YSI.........................................................................................69 1700/1725 Brannum Lane-P.O. Box 279, Yellow Springs, OH. 45387,USA. Contact: Tim Groms. T: 937 767 7241, 1800 897 4151 E-mail: applications such as oxygen, ozone, nitrogen, compressed dry air Adsorptech, Inc.................................................................17 22 Stonebridge Rd. Hampton, NJ 08827 USA. T: +1 908 735 9528 E-mail: events and exhibitions 4th Science and Technology CONFERENCE on Shrimp Farming...............................................................................73 November 30th - 1St, 2017. Cd. Ogregon, Sonora, Mexico. Contact: Christian Criollos, E-mail:

12th FIACUI.........................................................................59 September 27th - 29th, 2017. Guadalajara, Jalisco, Mexico. Information on Booths Contact in Mexico: Christian Criollos, | AQUACULTURE AMERICA 2017..............................................71 February 19th to 22nd, 2017. San Antonio, Texas. USA. E-mail: Information Services

Aquaculture Magazine.................................................1, 79 Design Publications International Inc. 203 S. St. Mary’s St. Ste. 160 San Antonio, TX 78205, USA Office: +210 504 3642 Office in Mexico: (+52) (33) 3632 2355 Subscriptions: Web portal · Newsletters · Magazine · Conferences · Technical Consulting. Machinery and equipment for manufacturing food E.S.E. & INTEC.......................................................................23 Hwy 166 E., Industrial Park, Caney, KS, 67333, USA. Contact: Mr. Josef Barbi Tel: 620 879 5841, 620 879 5844 E-mail: RAS SYSTEMS, DESIGN, EQUIPMENT SUPPORT AQUACARE..................................................................................53 T: 1 360 734 7964 Veolia Water Technologies.....................Inside BACK cover 250 Airside Drive - Airside Business Park - Moon Township, PA 15108 - USA T: +1-412-809-6641 Fax: +1-412-809-6512 SHRIMP FARM CORP. CAMARONERA LA PARRITA SA.......................................15 CostaRican Shrimp Farm for sale. tanks AND NETWORKING FOR AQUACULTURE Duro-Last, Inc.........................................................................39 525 Morley Drive, Saginaw, MI 48601 Contact: Jennifer Bruzewski T: 800-248-0280 E-mail:

Aquaculture Magazine February / March 2017 Volume 43 Number 1  

Global Blue Technologies A visionary intensive shrimp farm

Aquaculture Magazine February / March 2017 Volume 43 Number 1  

Global Blue Technologies A visionary intensive shrimp farm