Equinevet December 2014

The Modern

Equine Vet www.modernequinevet.com

hints for the foal eye exam Horse racing position cuts drag, saves energy Horse Cents: Is that degree worth it?

Technician Update: Colic due to Salmonella

Vol 4 Issue 12 2014

Table of Contents

Cover story:

4 Manifestations of ocular disease in the neonate Cover photo Shutterstock/Alexia Khruscheva

Racing

Horse racing position cuts drag up to 66%..................................................................... 7 Emerging Diseases

Horse virus sheds light on ebola replication...................................................................8 Horse Cents

Veterinary market improving, but value of veterinary degree unclear ...........11 Technician Update

Colic, enteritis and nasogastric reflex associated with Salmonella hadar.......14 News

APLU, AAVMC create antibiotic resistance task force.............3 Merial acquires two equine products from Bayer...............12 Grant helps to build new reference genome.........................12 UC Davis gets new ophthalmic laser.........................................13 G. Kent Carter new president of AAEP.....................................13 advertisers Avalon Medical.............................................................................................................................................. 3

The Modern

Equine Vet Sales: Robin Geller • newbucks99@yahoo.com Editor: Marie Rosenthal • mrosenthal@percybo.com Art Director: Jennifer Barlow • jbarlow@percybo.com contributing writer: Paul Basillo COPY EDITOR: Patty Wall Published by PO Box 935 • Morrisville, PA 19067 Marie Rosenthal and Jennifer Barlow, Publishers percybo media  publishing

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Issue 12/2014 | ModernEquineVet.com

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NewsNotes

APLU and AAVMC Create Task Force on Antibiotic Resistance in Production Agriculture WASHINGTON, DC — The Association of Public and Land-grant Universities (APLU) and the Association of American Veterinary Medical Colleges (AAVMC) created the Task Force on Antibiotic Resistance in Production Agriculture.

Composed of representatives from U.S. agriculture colleges/land grant universities and veterinary colleges, the production animal agriculture community and the pharmaceutical industry, the task force will advise the federal government on a research agenda and also help publicly disseminate information about the use of antibiotics in production agriculture. Officials from key federal agencies are expected to serve as observers to the task force and leaders from public universities in Mexico and Canada will serve as ex officio members.

“The task force will draw on the expertise of its members to serve as a knowledgeable and important source of advice for the federal government as it develops its plans. It can also make recommendations on further research that should be undertaken to develop alternative solutions for some antibiotic

use in production agriculture,” said Lonnie J. King, DVM, MS, MPA, DACVPM, chair of the task force and dean of The Ohio State University College of Veterinary Medicine.

In September 2014, the President’s Council of Advisors on Science and Technology (PCAST) released a report, Combating Antibiotic-Resistance, which laid out several recommendations to address the problem. President Obama has also issued an executive order that describes the antibiotic resistant bacteria problem as a national security priority and directs various executive branch departments and agencies to develop a plan of action by mid-February 2015 to address antibiotic resistance and protect public health. APLU and AAVMC support the goals articulated in the president's executive order and the framework provided in the PCAST report.

Once policies are established, APLU member institutions will help educate producers and the general public about the appropriate use of antibiotics in agriculture and veterinary medicine and the design of effective stewardship programs.

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ModernEquineVet.com | Issue 10/2014

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cover story

The initial ophthalmic examination of the neontate can have a significant impact on the foal's career, quality of life and value.

Photo courtesy of Dr. Sarah L. Czerwinski.

What to look for

during the neonate's

ophthalmic exam B y

The initial ophthalmic ex-

amination of the neonate can have a significant impact on a foal’s career, quality of life and value. While there are many anatomic and physiologic similarities between foals and adult horses, the two may manifest ocular disease in different ways, accord-

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P a ul

B a s ili o

ing to Sarah L. Czerwinski, DVM, BSc, resident in ophthalmology at the University of Florida Veterinary Hospital.

“A thorough ophthalmic examination is incredibly important for the identification and treatment of abnormalities,” she said here at the

61st annual American Association of Equine Practitioner’s convention in Salt Lake City. “These abnormalities can have a significant impact on the foal’s life and career.”

Cataracts can either be congenital or inherited. Common affected breeds include Thoroughbred,

Morgans, Belgians and Rocky Mountain horses.

“The lens focuses images onto the retina,” Dr. Czerwinski noted.

“The cataract blocks images, but it does not block light. A foal with a cataract will still have a dazzle reflex and an intact pupillary light response.”

Dr. Czerwinski explained it is important to note where the cataract is within the lens. Cataracts in the posterior pole of the lens are going to have the greatest impact on vision, and cataracts within the anterior part of the lens are going to be more likely to progress due to the addition of new fibers over time.

“To localize a cataract within a lens, use the slit beam on a direct ophthalmoscope,” she said. “Don’t look through the eyepiece. Instead, focus the beam on the cornea and sweep the light from side to side.

If the lesion is on the anterior part of the lens, it will move in the same direction as the cornea. If it is on the posterior part of the lens, it will move in the opposite direction.”

Cataract surgery has an initial high success rate in foals, but the long-term results are poor.

Microphthalmia

Microphthalmia, or an abnormally small globe, must be differentiated from phthisis bulbi. It is often idiopathic or secondary to uterine or other systemic disease. Common presentations for microphthalmia include a small palpebral fissure, prominent nictitans and a flat, small, orbit.

“The globe dictates the size of the orbit in the skull,” Dr. Czerwinski noted. “The difference will become more pronounced with time.”

Affected horses usually are blind and may also have entropion, chronic irritation and ocular dis-

charge. Enucleation may be indicated to restore comfort.

Persistent Pupillary Membranes

Embryologically, the iris forms as a sheet. The center part will regress to become the pupil. Any failure of that regression is called the persistent pupillary membrane. Focal opacities may be present in the lens or cornea, but vision is often unaffected. Surgical intervention is not typically required.

Dermoids

Dermoids are plaques of epidermal tissue in an abnormal location.

They are typically pigmented and may contain hair follicles, which can be irritating to the foal.

“We have a high rate of success with keratectomy or blepharoplasty, depending on the location,” Dr. Czerwinski said.

Aniridia

The iris forms the pupil, which modifies the amount of light that enters the eye. “With aniridia,” she said, “a horse or a foal is going to be very photophobic. This can manifest as blepharospasm or epiphora in bright light.”

The disease is rare, but Belgians, Quarter Horses and Thoroughbreds are overrepresented.

On examination of a normal horse, the leaflets of the iris block the veterinarian’s view of the ciliary body and the zonules that attach to the equator of the lens. Without the iris, the ciliary processes are visible as pigmented ridges. Small white lines also may be visible extending from the equator of the lens to the ciliary processes; these are the lens zonules.

Entropion

Entropion is one of the most

common acquired causes of ocular disease in foals. Lower eyelids are affected most often.

When the globe is displaced caudally in the orbit, the eyelids tend to roll inward. The inversion of the eyelid causes hairs from the lids to contact the cornea, which can cause ulceration and further retraction of the globe. “We need to break the vicious cycle of enophthalmos and entropion,” Dr. Czerwinski explained. “Temporary eversion of the eyelids is indicated. Avoid permanent corrections until the foal is fully grown.”

Several different methods of eversion will work, but the preferred method is to use an everting mattress suture with 2 to 3 sutures per lid. “Each bite of tissue is going to be about 5 mm, and the first bite should be 1 to 2 mm away

The Normal Foal

There are some key differences between the healthy eyes of a foal and those of an adult horse, according to Sarah L. Czerwinski, DVM, BSc, resident in ophthalmology at the University of Florida Veterinary Hospital. In foals, the iris is typically gray, and pupils are oval. “During the first month of life, the pupils are going to change into more of a horizontal shape.”

The optic disk is typically round and can range from pale pink to bright salmon-pink; the appearance of congestion may even be present. “You may see gray streaks radiating from the optic disks,” Dr. Czerwinski said. “That comes from myelin on the axons that comes from the retina and goes toward the optic disk to leave the eye. These streaks should be differentiated from retinal detachments or retinal folds.”

Lagophthalmos with an otherwise normal palpebral reflex is also a normal finding in very young foals. The appearance of a physiologic rotational strabismus will resolve after the first few days of life.

The menace response is absent in healthy foals; the reflex does not develop until about 2 weeks of age. “In the meantime, we need to rely on the dazzle reflex and observation of ambulation to assess vision in the foal,” Dr. Czerwinski noted.

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cover story

from the lid margin.” The distance of the second bite from the eyelid margin depends on how much eversion is required.

Dr. Czerwinski stressed the importance of using small, nonabsorbable sutures that can be left in place while the foal recovers.

Surgery tends to be indicated if there is greater than 50% stromal loss.

Courtesy of Dr. Dennis E. Brooks

Corneal Ulceration

The top picture shows aniridia in a foal. The bottom a melting ulcer.

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Ulceration of the cornea is common in neonatal foals because of the lack of a menace response.

Simple corneal ulcers are superficial, not infected, and involve minimal uveitis, while complicated ulcers are going to be deep and possibly melting. Surgery tends to be indicated if there is greater than 50% stromal loss.

“In foals, these melting ulcers will often be sterile, but culture them anyway,” Dr. Czerwinski said.

“The ulcers may not always be painful, so a Seidel test is important to detect full-thickness lesions.”

Treatment varies depending on the severity of disease, and includes administration of serum and selected antimicrobials every 1 to 4 hours.

Regardless of the disease, Dr. Czerwinski stressed the importance of fluorescein stain in all foals. “Foals may not manifest signs of ocular pain the same way that an adult horse would,” she said, “so staining is going to help to diagnose signs of pain from an ulcer, glaucoma or uveitis.” MeV

Racing

Horse racing position cuts drag up to

Jockeys who take advantage of

last horse reduced by 54% • Two horses running closely behind each other: drag of leading horse reduced by 6.5%, drag of trailing horse reduced by 38.5% • Five horses side by side: drag of center horse increases by 25% From these principles and further results, the energy expenditure can be calculated throughout the race of each individual horse, as well as the overall energy sav-

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ings when slipstreaming.

The research was conducted in the SportzEdge program of RMIT’s Platform Technologies Research Institute, with co-Chief Investigator Professor Simon Watkins and aerospace engineering student Kevin Stark.

MeV

Courtesy of xxxxxxxx

slipstreaming, or drafting, by running their horse behind or alongside others can reduce aerodynamic drag force by up to 66%, saving their horse critical energy, according to wind tunnel simulations done at RMIT University in Australia.

The simulations conducted in RMIT’s Bundoora wind tunnel, using toy models that are exact miniature replicas of a racing horse and jockey, are the first in the world to measure the effect of slipstreaming on horses through wind tunnel tests.

Prof. Franz “Tino” Fuss, said slipstreaming was a standard strategy in sports, such as cycling and speed skating, to save athletes’ power and energy.

“In a horse race, jockeys can use this same principle to give their horses an edge and help them reserve energy for that crucial final burst,” Prof. Fuss said, “Our research for the first time quantifies how much drag is reduced through different slipstreaming tactics in a horse race.”

The research showed the impact of different horse packs on drag (on average): •T wo horses in front of one horse: drag of trailing horse reduced by 66% •F our horses in a row: drag of

%

For more information: Published in the Australasian Science Magazine. January/February 2015. http://www.australasianscience.com.au/category/magazine-issue/januaryfebruary-2015 ModernEquineVet.com | Issue 12/2014

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emerging diseases

University of Utah research-

ers ran biochemical analysis and computer simulations of a livestock virus to discover an exotic mechanism to explain the replication of related viruses, such as Ebola, measles and rabies. The mechanism may be a possible target for new treatments within a decade.

“This is fundamental science.

It creates new targets for potential antiviral drugs in the next five to 10 years, but unfortunately would not have an impact on the current Ebola epidemic” in West Africa, said Saveez Saffarian, PhD, senior author of the study published in the journal PLOS Computational Biology.

Dr. Saffarian, a virologist and assistant professor of physics and astronomy, and his colleagues studied vesicular stomatitis virus (VSV), which is a member of the nonsegmented negative sense (NNS) RNA viruses. That family also includes closely related viruses responsible for Ebola, measles, rabies and the common, childhood respiratory syncytial virus (RSV).

The genetic blueprint in these viruses is an RNA strand that is covered by protein like beads on a necklace.

By conducting 20,000 computer simulations of the VSV starting to replicate in different ways, the study found a “fundamental mech-

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Using the horse virus, vesicular stomatitis virus, scientists think they may have found a way to target new treatments against Ebola virus. anism” used by VSV and related viruses like Ebola to make copies of themselves, Saffarian said.

Once the virus infects a cell, enzymes called polymerases literally slide along the protein bead-covered viral RNA strand until they reach the correct end of the strand.

Then the polymerases can read and transcribe the RNA code to synthesize messenger RNA, or mRNA. Once one polymerase starts doing that, it collides with other sliding polymerases, kicking them loose within the cell until they, too, attach to the correct end of the RNA and replicate to take over the infected host cell.

“The proposed sliding mechanism is a fundamental new mechanism specific to the NNS RNA viruses that can be a target for antiviral drugs in the future,” Dr. Saffarian said.

The sliding contrasts with replication in many other viruses,

in which the polymerases easily detach from the virus inside an infected cell and then find the right end of the RNA so replication begins.

He believes the discovery is “as fundamental as understanding the workings of HIV protease” – an enzyme essential for replication of the AIDS virus and became a target of protease inhibitors, which first made it possible for AIDS patients to live with AIDS as a chronic rather than deadly disease.

Many viruses have their genome or genetic blueprint hidden within an envelope of fat or lipid. The only parts of the virus that are exposed are some envelope proteins, and about 10% of those proteins are used by the virus to play a direct role in entering and infecting a target cell. Antibodies in vaccines target the proteins to attack and block viral infection.

But viruses quickly mutate different exposed proteins, making vaccines less than ideal – as demonstrated by the discovery that this year’s influenza vaccine doesn’t closely match the viruses circulating this flu season.

Some viruses, known as RNA viruses, have genetic blueprints made of RNA instead of DNA. Creating vaccines is particularly difficult for many RNA viruses – which include HIV, influenza and the group with

Courtesy of Dr. Saffarian

horse Virus sheds light on Ebola replication

This illustration depicts an exotic mechanism by which a family of viruses named NNS RNA viruses may replicate to make copies of themselves, according to a University of Utah study. The family includes vesicular stomatitis virus, as well as viruses responsible for Ebola, measles, rabies and RSV. The mechanism may serve as a target for new drugs against Ebola in five to 10 years. The yellowish strand is a viral genetic blueprint made of RNA and covered by bead-like proteins. The orange, ball-shaped objects are enzymes called polymerases, which normally read and copy the RNA to make new virus particles. That process can begin only when some polymerases attach to the correct end of the RNA and start reading it, which the two polymerases on the left are doing. The other polymerases (the four on the right side) are attached to the protein-covered RNA but slide along it until they collide with the polymerases that already are reading the RNA. Those collisions kick sliding polymerases loose (top center) so they can float to the proper end of the RNA and start reading it. Researchers hope future drugs can be developed to target this sliding mechanism as a new treatment for Ebola.

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emerging diseases VSV and Ebola “…because RNA viruses are adept at mutating and changing their envelope proteins to evade vaccines,” Dr. Saffarian said, adding that the Ebola virus now in Africa “is mutating extremely fast.”

So while “…promising vaccines candidates against Ebola now are being developed,” Dr. Saffarian said, “vaccines are not the most potent way to fight these RNA viruses.”

“The only way to create stable antiviral therapies against RNA viruses is to target multiple sites within the replication machinery,” he added.

“The replication machinery of the Ebola virus is not fully understood because it has not been possible to reconstitute replication of Ebola in the lab,” Dr. Saffarian said.

“It’s biochemically difficult."

The fundamental mechanism of replication has been shown to be almost identical to the well-studied VSV, which infects and causes bleeding mouth and udder ulcers in horses, cattle and pigs.

When an NNS RNA virus infects a cell, its RNA genetic blueprint enters the cell along with a set of polymerases, which are enzymes

essential for a virus to replicate.

Polymerases normally “read” the RNA genetic blueprint to synthesize mRNA, which then leads to formation of viral proteins and viral replication: more viral particles.

But in the NNS RNA viruses, the RNA strand is covered by bead-like proteins, preventing polymerases from reading the RNA and starting the replication process. Yet, the viral polymerases somehow evolved to read, transcribe and replicate the RNA genome hidden beneath the protein beads.

Researchers previously thought viral polymerases worked similar to the polymerases inside our cells, which move freely inside the cell and find the proper end of DNA to begin replication.

But in an initial phase of the study conducted with real VSV, they found that polymerases attached to the bead-covered RNA of VSV were so tightly bound, they could not float off into the cell to find the correct end of the RNA to start reading it.

They used computer simulation to test 20,000 different conditions that could possibly occur as

the livestock virus RNA was read and transcribed into mRNA in the first steps of viral replication.

The simulations were based on current knowledge of how much work polymerases do during the first hour after VSV infects a cell, and that each virus carries about 50 identical polymerase molecules to use for reading and copying the virus’ RNA into mRNA. The researchers looked for the mechanism that best fit the speed of a real VSV infection.

These viral polymerases have to be able to slide on their bead-covered RNA genomes rather fast to replicate. They can’t separate from the RNA, but they can slide, which helps the polymerases find where they have to start work at the end of the RNA. The study also indicates that as a polymerase reads and transcribes the beaded RNA strand, it collides with sliding polymerases and kicks them into solution inside the cell, which allows them to eventually bind to the correct end of the RNA, where they also start transcribing it MeV to mRNA for replication.

Eight exceptional veterinary students committed to careers in equine medicine received $2,500 scholarships from the American Association of Equine Practitioners Foundation and Markel at the AAEP’s 60th Annual Convention in Salt Lake City, Utah.

Now in its 26th year, the annual scholarship program awards financial support to fourth-year veterinary students who are proven leaders at their schools, advocates for equine welfare and academic achievers. Since inception of the program in 1989, 186 veterinary students have received more than $400,000 in scholarship support.

Congratulations to the following 2014 recipients: • Zachary Badura, Iowa State University • Elodie Huguet, University of Georgia • Rebecca Legere, Kansas State University • Molly Muedeking, Royal Veterinary College • Stephanie Regan, University of Florida • Holly Roessner, Michigan State University • Esther Rogers, Auburn University • Bailee Stanton, University of Saskatchewan 10

Issue 12/2014 | ModernEquineVet.com

Source: AAP

Vet students receive AAEP Foundation scholarships

“Markel has been a leader in equine insurance for many years,” said AAEP Foundation Chairman Jeff Berk, VMD. “We can’t thank Markel and its dedicated team enough for continuing its leadership by supporting this scholarship program.

“Equine veterinary students need help now more than ever, and Markel’s dedication is so important in helping these students MeV during difficult economic times.”

Horse Cents

Is that veterinary degree worth it? New figures question degree value, but show market picking up Economists from the American Veterinary Medical Association (AVMA) predicted that the market for veterinary services over the next several years would improve, but called into the question the value of a veterinary degree.

“The work presented at the 2014 Veterinary Economic Summit represents the first effort of moving beyond the ‘one-time’ workforce study by attempting more sophisticated analysis,” said Michael Dicks, PhD, AVMA director of veterinary economics.

“Many of the past studies have relied on assumptions where data or economic relationships are missing.

This summit replaces some of those assumptions with economic relationships acquired through quantitative analysis that uses data gathered from veterinarians in surveys.”

The AVMA conducted four economic surveys in 2014, including an employment survey, a survey of senior veterinary school students, a biennial economic survey and a capacity utilization survey. The Association of American Veterinary Medical Colleges also conducted a survey of veterinary college applicants.

“No other group has studied the veterinary workforce to the extent we have,” said AVMA President Ted Cohn, DVM. “No one has ever produced this type of data, and this information is critical to all of us if we are going to have informed, authoritative discussions about the state of the veterinary markets and what we can do collaboratively to improve them.”

The 2013 workforce study revealed excess capacity in the veterinary profession of 12.5%, meaning that 12.5% of veterinarians’ capacity to provide services was going unused. It did not indicate a 12.5% unemployment rate. This year, the AVMA reports that total excess capacity has dropped overall since 2012 and should remain under 10% for the foreseeable future. The percent of veterinary practices working at full capacity is up considerably from 35% in 2012 to 50% in 2014.

“Veterinary unemployment is at 3.4%, which is lower than the U.S. national rate of 6.1% and lower than even historically low unemployment levels,” he said. “This and other data show that the veterinary profession is able to absorb and employ veterinary school graduates.”

Dr. Dicks said that job growth in the veterinary sector will continue upward through 2025, with an accompanying drop in excess capacity.

“We are optimistic about these findings, but we also have to remain realistic,” Dr. Dicks said. “This is

all good news, but there’s some not-so-good news too.”

The AVMA and many other veterinary associations remain concerned about the debt-to-income ratio facing veterinary school graduates. Starting salaries for new veterinarians are flat since the last recession, while costs for education continue to increase. The research and surveys also show that the veterinary profession is vulnerable to downward turns in the economy, which became clear during and after the Great Recession of 2007-2009.

The research and surveys also show that the veterinary profession is vulnerable to downward turns in the economy, which became clear during and after the Great Recession of 2007-2009.

“We’ve learned that the veterinary profession and the demand for veterinary services are heavily influenced by the economy, as we took a large hit during the recent recession,” Dr. Dicks said. “We learned that for every $1,000 drop in personal disposable income, veterinarians see a nearly $1,700 drop in their practice income. Veterinary care spending, particularly for pets, is discretionary spending, and the recent recession provided added evidence of that.”

Dr. Dicks said that the ongoing collection of data will remain a focal point of the AVMA’s Veterinary Economics Division, and he reiterated that robust data collection by varied veterinary stakeholders is critical to helping paint a clearer picture of the veterinary business sector.

“We emphasized last year when the 2013 workforce study was released that the report and its findings are a starting point and not the end of our efforts to ensure adequate access to veterinary services and the economic viability of the veterinary medical profession,” he said. “We continue to subscribe to that philosophy today. We need even more data, and we are asking our colleagues across the veterinary profession to help us gather and analyze information for the benefit of the profession across all disciplines.”

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news notes

Merial acquires two major equine health products from Bayer Merial Ltd. has reached an agreement with Bayer HealthCare to purchase two Bayer equine health products, LEGEND®/HYONATE® (hyaluronate sodium) and MARQUIS® (ponazuril).

LEGEND/HYONATE is an injectable solution used in the treatment of noninfectious joint dysfunction in horses; and MARQUIS Antiprotozoal Oral Paste is the first FDA-approved treatment for equine protozoal myeloencephalitis (EPM), a disease that affects the central nervous system in horses.

The purchase, expected to be finalized in early 2015, further broadens Merial's portfolio of leading products that improve the health and performance of horses.

LEGEND/HYONATE is primarily sold in the United States and Canada, but is available in more

than 40 countries with the United Kingdom and Japan as important markets. MARQUIS is only sold in the United States and Canada. Merial plans to make both products available to veterinarians in countries around the world. The acquisition is subject to customary closing conditions.

Merial is a global leader in advancing the health of pets, horses and production animals. The company's global equine portfolio currently includes products to treat and prevent Equine Gastric Ulcer Syndrome and to control parasites in horses, as well as vaccines to help prevent Equine West Nile Virus, Potomac Horse Fever, equine influenza and rabies.

In October 2014, Merial launched its latest equine addition, with the EU approval of the updated equine influenza vaccine PROTEQFLU. MeV

University of Louisville Leads Study to Map Disease Genes in Horses

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Ted Kalbfleisch, PhD, of the University of Louisville received a three-year grant from the Morris Animal Foundation to research the horse genome.

on this earlier work. In the past five years, there have been dramatic improvements in sequencing technology as well as the computational hardware and algorithms required to analyze the data generated by the technology. Therefore, we now have the tools necessary to vastly improve the reference genome for the horse.”

The current reference genome for the horse, known as “EquCab2,” has been beneficial in studying horses and their genetic predisposition to disease, but it is not without its shortcomings, Kalbfleisch said.

The researchers intend to use new high throughput technologies to map the GC-rich regulatory regions. These GC-rich regulatory regions control how genes are expressed to participate in normal cellular processes. This work will enable scientists to better catalog genetic variation in these regions and understand how it affects health and performance. MeV

Shutterstock/RAJ CREATIONZS

LOUISVILLE, Ky. — The Morris Animal Foundation has awarded a three-year, $155,000 grant to a team of Kentucky and Danish researchers to build a new reference genome sequence for the domestic horse.

The sequence will be a much-needed tool for animal researchers worldwide and the equine industry in particular because it will significantly improve the ability to understand the role of genetics in the horse's health and wellbeing.

Ted Kalbfleisch, PhD, of the University of Louisville Department of Biochemistry and Molecular Biology, is the principal investigator on the grant.

He will be joined in the research with Ludovic Orlando, PhD, of the Centre for GeoGenetics at the National History Museum, University of Copenhagen; and James MacLeod, VMD, PhD, of the Gluck Equine Research Center at the University of Kentucky.

Genome sequencing allows researchers to read and decipher genetic information found in DNA and is especially important in mapping disease genes, discovering the diseases a horse might be genetically predisposed to developing.

“In 2009, Morris Animal Foundation helped fund the first genome reference sequence for the domestic horse,” Kalbfleisch said. “We intend to build

Laser treatment cyst before photo - A cyst is clearly visible in the lower section of this horse’s eye.

Source: UC Davis

The University of California Davis Veterinary Medical Teaching Hospital recently acquired a semiconductor diode laser device, which allows the ophthalmologists to perform new treatments on horses’ eyes, including cyst removal and glaucoma treatment.

Horses can develop cysts from their iris for no known reason. If left untreated, these cysts can grow and may cause irritation to the horse or become visually obstructive. Horses are also known to become “spooked” by seeing the cyst in their field of vision.

Removal of cysts is now a one-time, outpatient procedure. The laser simply “zaps” the cyst multiple times until it creates a hole causing the cyst to rupture and deflate, without damaging other vital structures in the eye. After care is generally a short course of topical anti-inflammatory ointment for no more than a week.

More importantly for horses, the laser can also be used to treat glaucoma, an increase in pressure inside of the eye. This increased pressure, if left untreated, eventually destroys the retina and optic nerve, and ultimately causes blindness. Glaucoma occurs due to an inability of aqueous humor to drain from inside the eye, most commonly secondary to equine recurrent uveitis (ERU) or “moon blindness.” ERU is very prevalent in horses.

The laser treatment for glaucoma is known as transscleral cyclophotocoagulation (TSCP), and destroys part of the ciliary body, which produces the aqueous humor that contributes to the increased pressure. TSCP treatment destroys just enough of the ciliary body to lower the production of aqueous fluid to a point that reduces the intraocular pressure, but not enough to completely stop the production, which the eye needs to remain healthy.

MeV

Source: UC Davis

Laser treatments increase equine ophthalmology offerings

Laser treatment cyst after photo - The cyst was successfully removed with a minimally invasive laser treatment

G. Kent Carter new president of AAEP G. Kent Carter, DVM, DACVIM, was installed as president of the American Association of Equine Practitioners (AAEP) at the association’s 60th Annual Convention in Salt Lake City, Utah.

A native of Levan, Utah, Dr. Carter entered private practice in Reno, Nev., after graduating from Colorado Source: AAEP State University College of Veterinary Medicine in 1979. He completed a residency in large animal medicine at Texas A&M University in 1982.

While working on faculty at Purdue University for two years, he became board certified in internal medicine.

In 1984, Dr. Carter joined the faculty of Texas A&M

University College of Veterinary Medicine and Biomedical Sciences, where he later served as section chief of internal medicine. For the past 20 years, Dr. Carter has collaborated with farriers to resolve equine hoof disorders and lameness. He founded an instructional rotation for students at Texas A&M dedicated to foot care and its ties to lameness.

An AAEP member since 1980, Dr. Carter has served on the Abstract Review, Farrier Liaison, Infectious Disease, Leadership Development, Nominating and Student Relations committees as well as a term on the board of directors from 2006-07.

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technician update

Colic secondary to enteritis and nasogastric reflux associated with Salmonella hadar The complete blood count results showed leucopenia (leukocyte count 4.6 x 10^3/ul, RI: 5.5 – 10.5 x 10^3/ul); neutropenia with a left shift (segmented neutrophil count = 2.6 x 10^3/ul, RI: 3.0 – 7.0 x A 17-year-old Quarter 10^3/ul; band neutrophil count = 0.2 x 10^3/ul, RI: horse mare presented to 0.0-0.1 x 10^3/ul); and had hyperfibrinogenemia Colorado State Univer(700.0 mg/dL, RI: 100.0 – 400.0 mg/dL). Neutrosity for colic lasting 24 phils were described as slightly toxic. hours. She was anorexic Chemistry values showed low hypophosphateand lying down frequently and was examined by the mia (1.1MG/DL, RI: 1.7 – 4.5mg/dL); hypocalcemia referring veterinarian that evening. She had a tem(10.9 MG/DL, RI: 11.5 – 14.0 mg/dL); and hypoperature of 102° F, reduced borborgymi in all four magnesiumemia (1.4 MG/DL, RI: 1.6 -2.2 mg/dL); quadrants, and a heart rate of 50 beats/min. an elevated total protein (8.0 GM/DL, RI: 5.8 – 7.4 She was given 1.1 mg/kg of flunixin meglumine gm/dL); hyperglobulinemia (5.1 GM/DL, RI: 2.5 – (Banamine, Merck Animal Health) IV and a na4.5 G m/dL), elevated CK (660 IU/L, RI: 100 – 470 sogastric tube was passed with a net of 6 L reflux IU/L), AST (397 IU/L, RI: 185 – 375 IU/L) and GGT obtained. She was comfortable throughout the eve(28 IU/L, RI: 10 – 25 IU/L). ning following initial treatment, but became mildly An IV catheter was placed and a bolus of 10 painful again the following morning.

L polyionic crystalloid fluids was administered On hospital admission she had a heart rate of 54 and then a maintenance rate of 3 L/hr was given beats/min, reduced gut sounds, a temperature of with calcium gluconate (5.6g/L) and magnesium 102° F and hyperemic mucous membranes. A na(400mg/L) added. A lidocaine CRI of 0.5 mg/kg/ sogastric tube was passed and 10 L of reflux was obhr was started as well and polymyxin B was admintained. An ultrasound showed small intestine with istered at 1000 IU/Kg every 12 hours. Ranitidine 6-8 mm wall thickness and normal peritoneal fluid. was administered at 1.1 mg/kg IV every eight hours, as well as flunixin meglumine at 0.7 mg/kg IV every 12 hours. Net volume of reflux obtained was 4 L/hr, which continued to be obtained over the course of 48 hours of hospitalization.

The following morning her temperature was 102.5° F, she had decreased gut sounds, and she remained hemiconcentrated despite fluid treatment with a PCV and TP of 45 and 7.5 gm/ dL, respectively. Throughout the day she continued to display signs of colic, was pacing and had muscle fasciculations. Subsequent abdominal ultrasounds throughout the day showed a dilated fluid-filled stomach, 5-6 cm dilated hypomotile loops Produced by the National Institute of Allergy and Infectious Diseases (NIAID), this digitally-colorized of small intestine with 3 mm scanning electron micrograph (SEM) depicts a number of Salmonella sp. wall thickness. An abdominal Courtesy of the NIH.

By Kristina Perry, BS, CVT, VTS-EVN

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Issue 12/2014 | ModernEquineVet.com

Atypical presentations of salmonellosis can include gastric reflux and ileus without diarrhea.

tap was performed, and serosanguinous fluid was removed and submitted for chemistry and cytology. Protein was 3.8 g/dL, nucleated cells were 1,470/ul. Cell type was 40% neutrophils, 40% large mononuclear cells, and 20% lymphocytes. It was described as a modified transudate. A venous blood gas showed a low PH of 7.3 and a mildly low ionized calcium (1.2 mm/L, RI: 1.3 - 1.9 mm/L).

Her condition continued to deteriorate over the 48 hours she was hospitalized and endotoxemia persisted. Based on her poor response to an aggressive medical therapy plan, she was euthanized.

Necropsy was performed and jejunum and Ileum had edema, mural thickening and a dull reddish mucosal coloration from the end of the duodenum to the cecum. Ileal mesenteric lymph nodes had acute hemorrhage and histopathology reflected Paneth cell metaplasia in the jejunum. Aerobic culture on feces grew salmonella Group C2, serotype Hadar. Cultures of the small intestinal contents within the affected bowel were positive for salmonella enteric, serovar Hadar, as well.

This case description outlines a clinically typical presentation of duodenitis/proximal jejunitis with uncharacteristic lesions of DPJ seen on necropsy that were later associated with salmonella cultured

from affected intestine. Salmonella typically presents clinically as enterocolitis with acute severe diarrhea and a protein losing enteropathy. This horse was protein conserving and did not have diarrhea.

Atypical presentations of salmonellosis can include gastric reflux and ileus without diarrhea, and horses can be carriers, shedding salmonella without any clinical signs of disease.

Since nosocomial infections are the most common source of salmonella outbreaks in equine hospitals, it must be considered as an etiology for horses presenting with anterior enteritis and/or colitis with precautions taken to limit exposure to other hospitalized patients. Salmonella has been cultured from gastric reflux and feces of horses post operatively in colic patients, as well as in horses being treated medically for DPJ indicating a need for biosecurity measures and the use of PCR and/ or culture in sick horses presenting for DPJ with or without diarrhea.

MeV

About the Author

Kristina Perry, BS, CVT, VTS-EVN, is an equine medicine and critical care nurse at Colorado State University Veterinary Teaching Hospital.

For more information: Sellon DC, Long M, eds. Equine Infectious Diseases, 2nd Edition, 2014 Saunders Elsevier, St. Louis,.

Reed SM, Bayly WM, Sellon DC, eds. Equine Internal Medicine, 3rd Edition, 2009 Saunders Elsevier, St. Louis,

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