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In this issue

Issue No. 2 Vol. 1 Second Quarter 2006

News

Technology in Focus

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Tateh Aqua Feeds unveils P. vannamei feeds

Unlike other shrimp feeds available in the market, Tateh shrimp feeds is an enhanced diet scientificllally formulated to satisfy the nutritional requirement of P. vannamei.

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Technology even for the poorest of the poor

A prawn farming technology through marine pen raising that even the low profile Filipinos can venture the said technology.

Our Cover:

Photo: D. S. Rito

The culture of whiteleg shrimp (Penaeus vannamei) in the country, has met with much controversy in the past, leading to the ban on exotic shrimp importation in the country. However, now that legalization of P.vannamei is in the air, there is much hope that the ‘miracle shrimp,’ which has been the saving grace of the shrimp industries in our neighboring countries, may bring back the old glory of our once wealthy shrimp industry. What challenges await us?

Technical Report

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The Philippine Native “Whites”

As contagious enthusiasm sweeps the Philippine shrimp farming community jumping into the Penaeus vannamei trend, while others remain hard-core, betting on Penaeus monodon, it is very encouraging to know how our biodiversity offers many other possibilities if all else fails or as long we are open to innovation.

SPF, SPR, and SPT: What are they about?

Health status and susceptibility of animals to infection or disease can be defined using terms specific-pathogen-free (SPF), specific-pathogen-resistant (SPR), and specific-pathogen-tolerant (SPT). The term “specific pathogens,” refers not to every known pathogen, but only for a specific one. These terms are explained further in the article.

NEWSFEED is a quarterly publication of Santeh Feeds Corporation. For inquiries, comment, and suggestion, please write to: NEWSFEED c/o Santeh Feeds Corporation Rm.601, 6F, West Trade Center 132 West Avenue, Quezon City, Philippines Telephone:+632.375.1563 Fax:+632.374.8031 Email: tateh.newsfeed@gmail.com URL: www.tateh.com

Phillip L. Ong HC Yean Advisory Board

Editorial

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It’s the right time for white

The time has come to face our fears. Our shrimp producers must face the reality that white shrimp is a good alternative to our ailing tiger shrimp industry. Let’s think more positively. Our neighboring countries faced similar problems, but their success in P.vannamei culture should challenge us and inspire us Filipinos, who in the past was one of the leaders, if not the leader, in shrimp culture in Asia.

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Feature

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Ulang a good alternative to sugpo

Joevar decided to try breeding ulang following the collapse of demand for monodon fry. He has also explored other high value species that might be worth breeding in his existing facilities, and has chosen ulang as best alternative because just like sugpo, ulang is also a crustacean, albeit a freshwater species.

Ma. Patricia I. Rico Riza San Juan Baby Chua Editorial Board

Daniel Cabrera Roy Ortega Helen Reyes Cristeta Cantos Dhonna Noriega Contributors

Dennis Rito Layout & Design


editorial

It’ or w hite It’ss the right time ffor white For about two and half decades now, the Pacific white shrimp P. vannamei has become the primary cultured species in the American continent. Also known as ‘miracle shrimp,’ it has been credited as the savior of many shrimp industries in Asia as well.

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n 2002, P.vannamei surpassed all other penaeid shrimp species in terms of production volume. In the American region alone, its production reached 213,800 metric tons (MT). That same year, Asia produced some 316,000 MT of the white shrimp. Asia’s leading producers are China and Thailand. This year, Thailand expects to produce some 300,000 MT of P.vannamei, 7.1% higher from its 2005 level.

Santeh Feeds Corporation has supported the government’s effort to implement its regulations and take full control in accrediting farms that want to grow the white shrimp. Through close coordination with the private sector, all stakeholders should work hand in hand to strictly enforce and follow codes of conduct and appropriate management practices in shrimp farming.

Back in 1995, the Philippines’ shrimp production peaked at 88,815 MT. Since then, production has steadily gone down, and in 2004 it only reached 35,916 MT purely, accounted for P. monodon species. For sure, we have been left behind by our neighboring countries’ soaring production volumes.

With the legalization of white shrimp in the country, those who have been culturing it secretly can now do it openly, thus paving the way for closer contact and coordination. We can learn from other countries like the USA (esp. Hawaii), Brazil, Venezuela and Thailand which were successful in implementing rules and regulations in P.vannamei culture. They succeeded despite early failures and disease outbreaks.

P.vannamei for commercial purposes made its way into Asia in 1996. Before that, P.monodon was the main species grown in the region. However, among the monodon’s many problems are slow growth rate, and disease vulnerability. When diseases White Spot Syndrome Virus (WSSV), Taura Syndrome Virus (TSV), Yellow Head Virus (YHV) and other viruses spread and plagued Asia’s giant tiger shrimp industry in early 1990s, the various shrimp industries in the region suffered major losses.

Market development, both for domestic consumption and exports, for P.vannamei is also an important consideration. Santeh believes that if the export market for white shrimp is already flooded by other Asian producing countries, and if we cannot compete through price, then why not develop our own domestic market? China has a very strong domestic market for shrimp.

The introduction of white shrimp however, provided Asian shrimp industries a way to recover and revitalize. China, Thailand, Indonesia, and Malaysia embraced the new species and their shrimp industries once again picked up. Our shrimp industry exerted efforts to keep monodon culture sustainable and profitable. Management systems were improved. Probiotics and bioaugmentators were made available. Despite these efforts, the industry has not succeeded in pushing itself back to the forefront. New technologies notwithstanding, P.monodon remained a poor performer. While the Philippines stuck to monodon, the shrimp industries in its neighboring countries not only have recovered, but are now soaring to their best performance. So why the reluctance on the part of the Philippines to culture P.vannamei? The biggest apprehension that holds us back is that an exotic species is a potential virus carrier, and its introduction may cause more harm than good. There are also fears that if P.vannamei will be commercialized, prices may soon fall. The time has come to face our fears. Our shrimp producers must face the reality that white shrimp is a good alternative to our ailing tiger shrimp industry. Let’s think more positively. Our neighboring countries faced similar problems, but their success in P.vannamei culture should challenge us and inspire us Filipinos, who in the past was one of the leaders, if not the leader, in shrimp culture in Asia. What has to be done to face the challenges of white shrimp introduction in the country?

It is a fact that Juan de la Cruz tasted seldom shrimp on his table as it is considered a luxury fare, something that is only eaten once in a while on special occasions. In 1993, a survey of the consumption of various fishery products of the BFAR showed that on a per capita consumption, shrimp consist less than 1 kg/ person/annum, which means we can potentially develop our domestic market. By culturing P.vannamei, shrimp will become more affordable for the average Juan de la Cruz. Since profitability depends on market price and production costs, P.vannamei’s high versatility in different culture system and its resilience makes it a perfect choice. Afraid of high production cost? We can actually play on the type of culture system—extensive, semi-intensive or intensive— depending on the type of market we are aiming for and thus ensure higher profitability. Certainly, all farming ventures must follow certain protocols and proper management systems to become sustainable. Our shrimp producers must bear in mind that environmentally sound shrimp farming is attainable through proper observation of carrying capacity as well as water treatment in most shrimp farms. Good aquaculture practices should be followed to the heart. Once and for all, P.vannamei culture is a promising venture, as the experiences of other countries proved it. It is unwise to continue relying solely on tiger shrimp when there is an alternative that would not only help revive the industry but make the business profitable and sustainable as well. Our shrimp industry deserves another chance. If the white shrimp (also called ‘miracle shrimp’) is the second chance for our shrimp industry, by all means, let’s take that chance.

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Second Quarter 2006

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news

Tateh Aqua Feeds unveils P. vannamei feeds The lifting of the ban on exotic shrimp species has paved the way for Penaeus vannamei culture to take off in the Philippines, and Santeh Feeds Corporation is on the forefront to meet the expected increase in demand for P.vannamei feeds. Bulacan-based Santeh, the maker of Tateh Aqua Feeds, has formulated and is launching a feed product line specifically designed for the whiteleg shrimp locally known as ‘hipong-puti.’ Unlike other prawn feeds available in the market, Tateh Vannamei feeds is an enhanced diet scientifically formulated to satisfy the nutritional requirement of P. vannamei. It is fortified with essential amino acids and precise levels of vitamins and minerals for optimum growth. Its highly selected raw materials promote nutritional natural immunity against stress. Tateh P. vannamei feeds is available from starter, grower, and finisher stage. For its specific product specification, please contact Santeh @ 023748031.Feeding guides for Vannamei using Tateh protocol is available upon request.

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news ‘Technology even for the poor of the poorest’

Sugpo can be raised in marine pens, BF AR says BFAR Calape, Bohol- Shrimp farming in the Philippines and other countries is an obvious expensive business venture due to its high cost of production including feeds, electricity, water management, and labor. Not now because the BFAR in region 7 (Cebu City) headed by Dionisio de la Pena discovered a prawn farming technology through marine pen raising that even the low profile Filipinos can venture in the said technology.

4.4 metric tons per hectare can be achieved. Prior to the stocking in pens, the post larvae were nursed in fishponds for 45 days.

In the said experiment, sugpo (Penaeus monodon) (PL 18-20) were stocked and reared using 3m x 3m x 3.5m fishpen at stocking density of 20/m 2. Although other trials were made at 10/m 2 and 30/m 2, 20/m 2 gave the best result in terms of harvest, survival rate and FCR using a commercial feed. Results showed that with this stocking density,

BFAR Director Malcolm Sarmiento, Jr. revealed that this project was part of the government initiative which aims to develop new low-cost technology for the Filipino people and in addition is part of the proposed 5-year development shrimp roadmap in collaboration with stakeholders to cover strategies in the industry including disease control, marketing and credit, postintroduction of new technologies and species among others.

The team revealed that compared with shrimps reared in fishponds, production seemed to be similar but with a much bolder cut in production cost due to big savings in production cost mentioned above.

TATEH KOMIKS

NEWSFEED

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technical report

The Philippine White Natives by Roy Ortega

As contagious enthusiasm sweeps the Philippine shrimp farming community jumping into the Penaeus vannamei trend, while others remain hard-core, betting on Penaeus monodon, it is very encouraging to know how our biodiversity offers many other possibilities if all else fails or as long we are open to innovation.

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he purpose of this article is to raise awareness concerning two of our promising indigenous white shrimp species, the Red tail shrimp Fenneropeneus penicillatus and Indicus shrimp Fenneropeneus indicus. Facts and anecdotal accounts about farming potentials of these species are presented and compared with the traditional crop P. monodon, and the trendy P. vannamei. These two native white shrimp varieties have been around with us since time in memoriam. They are interchangeably identified as “puti-an”, “pasayan”, “usbon”. “ligaw” or “lunhan”. Even taxonomists struggled naming them for example, Red tail shrimp was formerly classified as Penaeus indicus penicillatus, Alcock 1905 (in Holthius, 1980), something in between the old Latin name for Indicus shrimp, Penaeus indicus. In can be really confusing , please see pictures below:

Survival after harvest could spell success or failure in shrimp farming. Survival figures shows fairly equal for the four species, reflecting variety of culture problems are similarly encountered by these species in almost all farming regions (see Table 2). Knowing that P. monodon and P. vannamei are currently cultured at high intensities, much of the low survival can be deducible to viral and bacterial outbreaks. We can speculate that low values on the survival range registered by F. penicillatus and F. indicus are brought about by mundane farm troubles or inadequacy since viral infestations seem less common than other shrimp species (see Table 1). Still, viruses can easily infect other species, thus we should be vigilant from “no report” on specific viral infections on these alternative white species.

F. indicus Photo: www.fishesnpets.net

P. vannamei

Table 1. Disease cases among traditional & alternative shrimp/ prawn species * (see page 11 )

F. penicillatus

Photo: www.fish.org.tw

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Being native species means there are no biosecurity-related legal restrictions imposed by any local institution to any kind or level of culture operation of F. penicillatus and F. indicus. On the other hand, the primary technical objection to P. vannamei is concerning the potential translocation of dreaded foreign diseases such as the Taura (see Table 1) and other virions. Current knowledge shows the two native white species F. penicillatus and F. indicus carry lesser viral load than P. monodon and P. vannamei. If low-risk to disease would be our critical criteria for sustained production, F. penicillatus and F. indicus would be a logical alternative; while the so called SPF or SPR P. vannamei stocks is yet to prove its value and utility in our local farming conditions. The disease laden condition of P. monodon was concomitantly brought by abusive culture practices and possible genetic deterioration. Prophetically speaking, aquaculture of any shrimp species could end-up this way if we fail to correct our mal-practices in the past with P. monodon. Finally, biosecurity measures must always be followed in the transport of any shrimp brood-stock or stocking materials since viral cross-contamination is very unpredictable and costly to control.

Generally speaking, it appears that farming performance of F. penicillatus and F. indicus and P. vannamei in many ways are comparable, but still apart from P. monodon productivity (see Table 2). The average size at harvest is practically equal for F. penicillatus, F. indicus and P. vannamei, and they are barely half of attainable size for P. monodon. This size disparity translates


technical report to price difference, for crustaceans in general, bigger size fetches higher price over smaller ones of the same species and amongst other species. Thus, we do not expect F. penicillatus and F. indicus and P. vannamei encroaching P. monodon markets due to size preferences, unless the later species are intentionally grown close to their matured sizes (i.e. 50-70 g in 10 mos P. vannamei breeders (Wickins and Lee, 2002), but meat quality is not known if comparable with the former.

been seasonally (i.e. March to May) producing F. penicillatus or F. indicus post larvae, but by order basis only. In addition, Jose Vaga’s Aquarius Hatchery in San. Felipe Zambales claims to have produced and traded native white shrimps post larvae. Meanwhile, the Aquaculture Department of SEADEC in Tigbauan Ilo-ilo is mustering its resources to package hatchery technology of F. indicus available to shrimp farmers. SEAFDEC/ AQD pioneered the hatchery technology of P. monodon in Southeast Asia, circa 1980’s.

Table 2. Global data on the culture performance of alternative shrimp/prawn species available in the Philippines* (see page 11)

Table 3. Collated 1987-1990 production performance of Red tail shrimp F. penicillatus in Taiwan* (see page 11)

In most farmed aquatic animals, crowding has been proven to affect growth and final size distribution of animals. Obviously P. monodon is less tolerant to crowded conditions unlike the F. penicillatus, F. indicus and P. vannamei. Easiness in crammed conditions compensates for small average size at harvest, in effect increases total biomass at harvest. Although limited by crowding conditions P. monodon‘s bigger individual size pays off giving appreciable tonnage at harvest. From the figures above, it appears that average sizes at harvest of F. penicillatus, F. indicus and P. vannamei is not affected by stocking density, thus its smallmedium size is apparently genetically imposed, not until selective breeding paves way for “Giant white shrimp”. Since F. penicillatus and F. indicus are resident species, we can benefit from the vast gene pool for trait improvements in the future. Extensive and protracted culture of these white shrimps could produce larger than average animals, comparable to medium sized P. monodon.

Red tail shrimp Fenneropeneus penicillatus and Indicus shrimp Fenneropeneus indicus are not at all new or unfamiliar to Filipino shrimp farmers. They are in fact what we call “usbon” or “ligaw”, meaning incidental crops in our P. monodon grow-out ventures. Both Vargas and Boreli (pers com., June, 2006) said that F. indicus and or F. penicillatus are suitable during high summer when salinity is rather high. Their costumers complain that stocks start to “dissolve” when monsoon rains is persistent. The supposed high salinity tolerance of these native white shrimps could fit in many brackish water ponds of Pangasinan, Bataan and Zambales where high salinity limits the culture of P. monodon and P. vannamei. The F. indicus and or F. penicillatus are farmed (mono-crop) in Bicol area at extensive levels yielding around 500 kilos in three to four months (1- 5 Pl/m2 with 50 % survival of 25-30 g shrimps) (Boreli, pers com., June 2006). This apparent low productivity means there are still many things to unravel, thus offers huge space for technological improvement.

Ideally, shifting to alternative species should be technologically compatible with traditional crops and must cater for the market niche. Unconfirmed reports claimed it was the Red tail shrimp F. penicillatus that saved Taiwanese farms from total closure after the P. monodon boom and bust, mid 1990. Presumably, F. penicillatus culture is primarily based on intensive P. monodon technology (see Table 3), but polyculture and inter-cropping with other pond raised brackish water species have also been reported (Wickins and Lee, 2002). It is also said that the “white shrimp” production of Taiwan and southern provinces of China were chiefly Red tail shrimp F. penicillatus mixed with P vannamei which came in later than the former also native in the area . How could custom inspectors of importing countries tell which is which once they have been peeled and cooked, anyway they are same branded as “white shrimp”.

It is worth considering some of our promising indigenous white shrimp species for aquaculture. While they are here and the entry of P. vannamei is becoming unstoppable as the shrimp industry cries out for its final commercialization, why should not we pursue them in parallel? Our species selection should not be a case of either / or, but should make use of our aquatic biodiversity leverage. There has got to be reasons why they are swarming in our waters!

Strong hatchery technology proved to be one of the keys for viable aquaculture. Year-round farming of these native white shrimp species is hampered by weak hatchery technology backup. A certain Jimbo Hatchery, owned & operated by Mr. Jimmy Boreli in Mercedes, Daet Camarines Sur, is reported to have

References Bondad-Reantaso, M.G., McGladdery, S.E. East, I., and Subasinghe, R.P. (eds.) Asian Diagnostic Guide to Aquatic Animal Diseaseas. FAO Fisheries Technical Paper No. 402, Supplement 2. Rome, FAO. 2001. 240 p. Holtius, L.B., 1980. Shrimps and Prawns of the World: An Annotated Catalogue of Species of Interest to Fisheries. FAO Fisheries Symposium No. 125. vol. 1 xvii + 271. Rome Italy. Taiwan Agriculture Encyclopedia, Fishery Edition. P. 228-230. Wickins, J.F. and D.O’C, Lee. 2002. Crustacean Farming: Ranching and Culture 2nd edition Blackwell Science Ltd Osney Mead, Oxford OX2 OEL England. Personal Communications Mr. Jose Vargas, Hatchery operator (P. monodon and F. indicus/F. penicillatus), June 8, 2006 Mr. Jimmy Boleri, Hatchery operator (P. monodon and F. indicus/F. penicillatus), June 8, 2006

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feature

Ulang a good alternative to sugpo Text and photos by Daniel Cabrera

F

or years, the aquaculture industry was driven by the culture of the black tiger shrimp (Penaues monodon), attracting many to venture into shrimp farming and related businesses. However, when viral diseases struck, the industry suffered a huge setback from which it has never fully recovered. Many affected businesses either folded or faded away, however, there are some that continued. Among these are the prawn hatchery ventures of Avelino Lee and Jose Vargas.

Mr. Jose Vargas (L) & Mr. Avel Lee (R)

Both Lee and Vargas have been running prawn hatcheries for nearly 13 years in San Felipe,Zambales. Even as demand for P.monodon Pl has declined, they continue to operate their hatcheries, however both have been on the lookout for other opportunities. They found such an opportunity in the ulang (Macrobrachium rosenbergii), a high value crustacean that can be cultured in freshwater both in a monoculture system or a polyculture system with tilapia in ponds or in tanks. Lee and Vargas are now gradually converting some of their hatchery facilities into an ulang hatchery. Ulang

Gold Coast Hatchery and Aqua Gold Hatchery Of his eight prawn hatcheries, Mr. Lee has converted his Gold Gold Coast Hatchery and Aqua Gold Hatchery into ulang hatcheries. Each can produce an estimated 50 million PLs per cycle. Although Mr.Lee is a newcomer in ulang PL production, he and his team already has a head start, as their expertise in prawn hatchery protocol give them an edge to easily perfect the breeding of ulang. Siegfred Tuscano manages Gold Coast while Paul Casitas manages Aqua Gold hatchery. Their production process for ulang post-larvae (PL) follows. First, they acquired wild ulang breeders from Arayat, Pampanga and some parts of Bulacan. These breeders were

transported to San Felipe, where they are placed in a breeding tank measuring 1x 1 x1.5 meters at a stocking rate of 40pcs/ tank.They were fed with trash fish and some mollusks like oyster and squids. After a week, the female breeders developed eggs in their abdomen. Paul Casitas,Aqua Gold technician said that each breeders can produce 10,000 PL per spawning. Ulang eggs color in the abdomen indicates maturity. Gray eggs will hatch after one day, while a yellow or orange egg will hatch in 5-7 days. “Ideally, the number of breeders in the tank should have been 10 pieces but since the breeders were not spawning simultaneously, we decided for 40 pieces,” Casitas further reiterated. The mysis, or the newly hatched eggs, were then transferred to larval tanks where they stayed for five days. Diets for larvae include Japonicus zero, Brachionus plicatilis, artificial plankton and dry cell (solution type). The breeders were transferred in ponds and after a couple of weeks were again seined for another breeding cycle. Twenty days after, eggs will again be produced. Usually, mortality occurs during transport due to stress.

Indoor tanks

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For water management, Mr.Lee’s technicians simply changed the water daily for a certain water level percentage. Tank bottom siphoning as well as regular cleaning of the tank with soap and water is a must. The tank is also aerated using a 7.5-horsepower (HP) in 24 hours duration.


feature Mr. Lee’s new passion for ulang was actually inspired in Thailand, where he saw how progressive ulang culture is. By press time, both Gold Coast and Aqua Gold will already have PL ready for market. For inquiry of ulang post larvae, interested parties may contact Siegfred Tuscano of Gold Coast Hatchery, San Felipe, Zambales @ 09178965328 or Paul Casitas of Aqua Gold Hatchery, San Felipe, Zambales @ 09178965327.

Aquarius Prawn Hatchery

Currently, he is using small 300-liter tanks that can hold 80,000 PL per stocking. Such a volume is more manageable and allows easier monitoring of all critical water quality parameters. For his trial, the PL survival and recovery is 80%. in one time stocking. The said water volume is more manageable and easier to monitor all critical water quality parameters. In terms of survival, PL recovery in his farm is 80%. At PL1 stage, Joevar observed that the ulang is larger than sugpo, which he thought was the result of the ulang’s big head appearance. The mysis stage lasted 35 days, and 16 days later, these metamorphosed into post-larvae. At PL10, larvae growth accelerated rapidly at preferred salinity of 12ppt. Though the population contained uneven sizes, smaller sizes can still cope up with the bigger ones as days goes by. “We observed that input of freshwater is inducing special growth in the ulang, maybe because it is in the nature of catadromous species which grow in freshwater but moves to brackishwater to spawn. The newly-hatched larvae will again move to freshwater to grow to its maturity,” explained Joevar. For his trial, he selected ulang breeders that are 10-12 cm size (from rostrum to tail). One breeder can produce 10,00030,000 mysis. Fully grown or matured over-size, breeders can spawn up to 80,000-100,000 mysis.

Breeding tanks

Not too far away in San Felipe, Jose Vargas, more commonly referred to as Joevar by his friends, is also doing his share in breeding ulang. Joevar decided to try breeding ulang following the collapse of demand for monodon fry. He has also explored other high value species that might be worth breeding in his existing facilities, and has chosen ulang as best alternative because just like sugpo, ulang is also a crustacean, albeit a freshwater species.

Joevar added that ulang can be cultured alone in pond, or in polyculture with tilapia. In growing ulang with tilapia, his advice is to stock ulang one month ahead of tilapia to avoid cannibalism. He is currently selling his ulang PL at P1.25 per piece with 10% mortality allowance. Interested buyers may get in touch with Mr. Jose Vargas @ 0919.4268.912/0921.3641.267

Mr. Joe Vargas of Aquarius Hatchery Farm

He explained that ulang prefers temperature of 240C. Although its ideal temperature range from 28-31o C, lower temperature would mean slower growth. Joevar revealed that ulang is highly sensitive to temperature, so much so that one degree fluctuation will result to mortality. Another important water quality parameter is the pH level. The ulang, he said for him prefers pH levels of 7 to 7.2. Because of this, tanks are regularly siphoned to remove dirt and debris and to keep the water clean and clear. Joevar emphasized that it is better to use smaller facilities like tanks when breeding because these are easier to handle.

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technology in focus Health status and susceptibility of animals to infection or disease can be defined using terms specific-pathogenfree (SPF), specific-pathogen-resistant (SPR), and specific-pathogen-tolerant (SPT). The term “specific pathogens,” refers not to every known pathogen, but only for a specific one. These terms are explained further by the following article.

SPF, SPR,and SPT: What are they about? lost. They will no longer be considered SPF, even they tested negative by polymerase chain reaction (PCR) or other diagnostic tests, as they might be infected at a level below the limit of detection of the test.

Photo: www.rugierriphoto.com

Specific P athogen-F ree Pathogen-F athogen-Free

S

pecific pathogen-free status is gained by specific management conditions where pathogens are excluded from the culturing facilities. This is a common strategy for domestication programs. SPF animals are free of one or more specific pathogens, but this health status does not refer to their susceptibility to infection or disease. In addition to being SPF, animals may or may not be resistant or tolerant to the same or other pathogens. True SPF animals have not been exposed to pathogens, and their SPF status is a transient one. Once these animals are exposed to an environment where a range of pathogens-especially those for which their SPF status is designated-is present, their SPF status is

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SPF animals are safer than any other group of animals in avoiding the transboundary movement of pathogens. However, unknown pathogens or pathogens not included in the screening for SPF status can still be present and/or go undetected. Also, it is becoming clear that different strains of certain pathogens may not be detected by some of the commonly used tests. These undetected strains of pathogens pose a risk in pathogen movement through uncontrolled traffic in aquatic animal stocks.

Specific Pathogen-Resistant Animals gain “resistant” status because of their genetic background. They can be resistant to infection (SPR) or resistant to disease, as in tolerant to a pathogen (SPT).As with SPF, resistance is specific for a particular pathogen. SPR animals are not susceptible to infection and present no risk of transmission of the particular pathogen, provided there is no “mechanical” contamination through any viable pathogen adhering to the gills or other surfaces. If these animals have not been exposed to pathogens, they can also have SPF status. Pathogen resistance is a qualitative characteristic. An animal is either resistant or it is not, and the status is permanent.

SPR status for a particular pathogen is not lost due to management practices, although it can be lost in subsequent generations through poor animal-breeding and selection strategies.

Specific P athogenTolerant Pathogenathogen-T SPT animals either do not develop the disease, or if they do get infected with the specific pathogen for which tolerant status is conferred, the impact is not as severe as in regular animals. Tolerance is a quantitative characteristic. For example, there might be different degrees of tolerance to the pathogen or environmental factors may have less influence on the development of the disease. If SPT animals have not been exposed to pathogens, they can also have SPF status, but being susceptible for infection, they cannot be SPR for that same pathogen. Unless these animals are also SPF, they are potential carriers of pathogens and therefore present a risk to spread diseases.

Shrimp Industry Implication It is important that a grower or hatchery operator should secure an SPF, SPR and SPT type of breeders or stock to avoid possible disease outbreak in farm. Source: (Global Aquaculture Advocate) February 2003 Volume 6 Issue 1. Health section. Victoria Alday de Graindorge, PhD. p.42


technical report Table 1: Disease cases among traditional & alternative shrimp/ prawn species*

*Collated from Bondad-Reantaso et. al., 2002

Table 2: Global data on the culture of performance of alternative shrimp/ prawn species available in the Philippines*

*Modified from Wickins and Lee, 2002

Table 3: Collated 1987-1990 production performance of Red tail shrimp F. penicillatus in Taiwan*

*Taiwan Agriculture Encyclopedia, Fishery Edition

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*collated from Bondad-Reantaso et. al., 2002

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