The Modern Equine Vet September 2015

The Modern

Equine Vet www.modernequinevet.com

Distal Phalangeal Bone Lesions appear early in laminitis

Additional diagnostics can help evaluate carpal sheath effusion Minimizing the subjective Dr. Stephanie Valberg to join Michigan State

Vol 5 Issue 9 2015

Table of Contents

Cover story:

Distal phalangeal bone 4 lesions appear early in laminitis Cover:Shutterstock/Theunis Jacobus Botha

Orthopedics

Additional diagnostics can help evaluate carpal sheath effusion..........................8 Minimizing the subjective; mistakes in diagnostic analgesia...............................10 Hematology

Better use of equine thromboelastometry..................................................................12 News

Traveling through The Ark.................................................................14 New study to identify risk of transplanting horses..................14 Dr. Stephanie Valberg to join Michigan State University.15 Manage flies with wasps instead of pesticides.....................15 New EPPH research projects looking for funding ..............16 OSU opens equine health center.............................................17 advertisers Merck Animal Health.................................................. 3 Lifeline Performance Supplements......................... 5

Luitpold Animal Health.............................................. 7

The Modern

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cover story

Distal phalangeal bone lesions appear early in laminitis

Lesions in the distal phalangeal bone (Cof-

fin bone, P3) occur very early in equine laminitis and could contribute not only to the progression of lamellar lesions, but also to the pain a horse with laminitis feels, according to a recent study from the New Bolton Center in Kennett Square, Pa., which is part of the University of Pennsylvania, College of Veterinary Medicine.

The structures of the hoof wall capsule, inner hoof wall lamellae and the distal phalangeal bone are highly integrated and share a blood supply through specialized vascular channels that extend from the medullary cavities of the bone through the dorsal cortex to the lamellae, explained Julie Engiles, VMD, DACVP, assistant professor of pathology in the department of pathobiology at New Bolton.

“Coinciding with the onset and progression of equine laminitis, our study identified several changes in the distal phalanx, including bone remodeling, medullary inflammation and fibrosis, and vascular lesions,” she said. “This study further supports a physiologic and pathologic link between bone and the lamellae of the equine foot, and has potential applications regarding laminitis pathogenesis, as well as pain.”

In the study, the researchers reviewed the pathology in 36 equine front and back hooves taken during necropsy from 15 horses, aged 1 to 22 years. The horses were separated by whether they had been a performance (6 laminitis and 3 controls) or nonperformance (4 laminitis and 2 controls) horse.

At the start of the study, 10 of the horses had laminitis and five did not based on history, clinical signs and radiographic evidence, but micro-computed tomography (CT) and histology showed that some of them had laminitis that was not clinically recognized, e.g. “subclinical laminitis,” the study found.

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cover story

The researchers made two biaxial parasagittal sections of each foot with a bandsaw and took non weight-bearing post mortem radiographs of all sections, which were then graded radiographically, grossly and microscopically according to absence or presence of laminitis to separate mild, early laminitis, which might not be apparent on radiographs, from more severe cases. The histopathology of lamellar and bone sections were compared with microCT scans to correlate laminitis with distal phalangeal lesions.

Although this multimodal grad-

ing system standardized variables and enabled detailed pathological summary of the lesions associated with the development and progression of laminitis, this system would not be applicable to clinical medicine, Dr. Engiles explained. “However, this system best characterizes laminitis lesions in horses with either early disease or multiple feet affected, where oftentimes there is a tremendous variability among the different feet regarding laminitis severity, distribution and duration,” she said.

Thirteen feet from eight horses represented severe, overt and

Figure legend Composite image of gross photos (left), microCT 3D images of the distal phalanges (middle) and histology of the distal phalanges (right) from normal, acute-severely laminitic (sepsis/inflammatory origin), and chronic-severely laminitic feet (support-limb overload and endocrinopathic origins of 3 month and 10 year duration, respectively). Grossly there is hoof wall separation (acute laminitis) and progressive rotation with lamellar wedge formation (chronic laminitis). MicroCT images show progressive bony remodeling and architectural distortion that is apparent in the acute laminitis and markedly severe in the chronic laminitis cases.

Histology shows replacement of normal medullary fat with inflammatory cells (asterisk, acute laminitis) and osteoclast activation with bone remodeling (arrows, acute laminitis). Chronic bone activation results in bone fragmentation, medullary fibrosis and vascular sclerosis. Image courtesy of Dr. Engiles.

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long-standing laminitis, which was clearly visible on radiographs. The researchers wrote, “Lesions included severe rotation and displacement of the distal phalanx with lamellar wedge formation with lamellar hyperkeratosis, marked primary epidermal lamellar displacement, elongation and distortion.”

MicroCT scans and histology of the distal phalanges from severely laminitic feet showed marked distal phalangeal bone loss and remodeling with severe inflammation, fibrosis and vascular lesions.

However, the researchers also found that of 15 feet from eight horses having no history, radiographic or gross signs of laminitis, eight feet from five horses had mild acute histological manifestations of laminitis, suggesting subclinical disease, and 6/8 feet (75%) had at least one risk factor for laminitis. Mild histological findings in these milder or more acute cases included elongation, thinning and aberrant contours of the secondary epidermal lamellae. Albeit less severe than the changes described above for severe chronic laminitis, according to the researchers, distal phalangeal lesions (porosity, remodeling, inflammation and early fibrosis) were also identified by microCT and histology in bones from feet with mild or acute laminitis. Of note, in this particular hospital population, the performance horses tended to have orthopedic and sepsis-related risk factors, while the non-performance horses tended to have metabolic/endocrine risk factors for laminitis.

“Although distal phalanx lesions were radiographically apparent in severe/chronic laminitis, microCT and histology revealed changes that were not radiographically apparent in mild/acute laminitic feet,” the researchers wrote.

“Typically, distal phalangeal lesions are not recognized until laminitis is severe and long-standing,” Dr. Engiles said. “Commonly rec-

ognized lesions include remodeling and fractures of the solar margin, or ‘tip’ of the distal phalanx.

Standard radiography is not sensitive enough to identify early bony lesions described in this study, and therefore wouldn’t be anticipated by the veterinarian.”

Bone remodeling in humans and animals initiated by inflammation, neoplasia or hemodynamic alterations including bone marrow edema, infarcts and neovascularization is especially painful, she explained. “If the distal phalangeal lesions identified in this study contribute to activation and sensitization of nociceptive and neuro-

pathic pathways that are associated with bone pain, then it provides another explanation for the severe pain and debilitation observed in laminitis, which has many similarities to complex regional pain syndrome,” Dr. Engiles said.

“If it is indeed the case, then this research may also provide additional therapeutic opportunities for laminitic horses. For example, bone pain in humans and in animal models has been successfully treated with pharmacologic agents that inhibit bone remodeling, such as bisphosphonates and RANKL (osteoclast) inhibitors,” she said.

“Distal phalangeal bone lesions

associated with equine laminitis occur very early in the disease process, much earlier than previously recognized. The lesions in the bone could significantly contribute to pain associated with laminitis as well as progression of lamellar lesions by interfering with the shared blood supply,” she said.

Although these early changes in the distal phalanx were not typically found on radiographs, they might be picked up by high resolution CT or magnetic resonance imaging in live animals, she added, which could lead to earlier intervention and lessen the severity of the disease.

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For more information: Engiles JB, Galantino-Homer HL, Boston R, et al. Osteopathology in the equine distal phalanx associated with the development and progression of laminitis. Vet Path 2015 52(5): 928-944. doi: 10.1177/0300985815588606 . http://vet.sagepub.com

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Orthopedics

Additional diagnostics can help evaluate

carpal sheath effusion B y N i k H a w k i n s U n i v e r s i t y o f W i s c o n s i n

they evaluate horses with carpal sheath effusion to accurately determine and treat the underlying cause, according to researchers at the University of Wisconsin School of Veterinary Medicine.

Although it’s not a common issue, some horses will experience swelling behind the carpus, which is often referred to as the knee joint of the equine forelimb but is actually more akin to the human wrist. This condition, called carpal sheath effusion, can be a serious problem for active horses because it usually points to underlying bone, tendon or ligament damage that hinders movement and performance.

Frustrating endeavors

Diagnosing the cause of carpal sheath effusion and predicting how well it will heal are notoriously frustrating endeavors for veterinarians. While the bulk of published research points toward bone injuries as the root of the problem, 8

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Photo courtesy of Ronald Genovese

Veterinarians can alter how

Findings from a recent SVM study suggest that ultrasonographic evaluation of horses with carpal sheath effusion, as shown here, should include additional parts of the forelimb.

clinical observations seem to point in a different direction, according to Ronald Genovese, VMD, an equine veterinary practitioner for more than 50 years, and Joan Jorgensen, DVM a boarded equine internal medicine veterinarian and associate professor of comparative biosciences at the School of Veterinary Medicine.

“Our overall impression from treating cases was that carpal sheath effusion was most common-

ly caused by injuries to soft tissue— tendons and ligaments, not bone— and that the injuries extended the full length of the forelimb, not just at or below the carpus,” said Dr. Jorgensen. “But no prior study has really explored the incidence of the different injuries that are suspected to cause or be associated with carpal sheath effusion.”

Observations also led Drs. Jorgensen and Genovese to believe that older, less athletic horses were

more at risk for the condition. If their hunches turn out to be true, it would mean veterinarians could make significant changes in how they evaluate horses with carpal sheath effusion. They enlisted the help of Dörte Döpfer, DVM, MSc, PhD, associate professor of epidemiology at the school of veterinary medicine, and Matthew Stewart, PhD, MVet, BVSc, associate professor in the College of Veterinary Medicine at the University of Illinois, to put their theories to the test.

The team gathered and analyzed clinical records, radiographs and ultrasonographic findings for 121 horses, patients at Cleveland Equine Clinic, where Dr. Genovese now practices, and the former Randall Equine Veterinary Group—representing virtually every equine breed, discipline and age. The findings supported their clinical impressions, opening the door to new ways that will help equine practitioners understand and treat this challenging injury.

Bone injuries were associated with carpal sheath effusion in only

The researchers recommended that horses diagnosed with carpal sheath effusion continue to be evaluated by radiology to rule out bone involvement.

8% of cases in the study, suggesting that the current scientific literature vastly overrepresents underlying bone abnormalities. Instead, as they suspected, more than 90% of the horses with carpal sheath effusion suffered from soft tissue damage.

In addition, most cases involved complex injuries to multiple structures. The worst injuries extended into structures above the carpus, an area that is often overlooked.

Based on their findings, the researchers recommend that horses diagnosed with carpal sheath effusion continue to be evaluated by radiology to rule out bone involvement.

Perhaps most critically, the study suggests that evaluations should also include an extensive ultrasonographic examination of the back of the forelimb from the level of the mid-radius to the fetlock. Special attention should be paid to the superficial digital flexor muscle, deep digital flexor muscle and accessory ligament of the superficial digital flexor tendon, areas where the study found injuries to be most common.

“Just like in people, the middleaged and older horses were at higher risk for developing soft tissue injuries along with carpal sheath effusion,” said Dr. Jorgensen. “And these injuries were substantially more severe and associated with MeV more lameness.”

For more information: Jorgensen JS, Genovese RL, Döpfer D, Stewart MC. Musculoskeletal lesions and lameness in 121 horses with carpal sheath effusion (19992010). Veterinary Radiology & Ultrasound 2015;56(3):307-316. http://onlinelibrary.wiley.com/doi/10.1111/vru.12241/abstract

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ModernEquineVet.com | Issue 9/2015

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orthopedics

Minimizing the

Subjective Potential Mistakes in Diagnostic Analgesia B

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Photo courtesy of Equinosis (Lameness Locator) • www.equinosis.com The difficulty with subjective

assessment lies in the very definition of the word “subjective.” Errors in judgement, biases, or missed nuances can lead to a misdiagnosis or direct the clinician to administer problematic treatment, according to Michael Schramme, DrMedVet, CertEO, PhD, DECVS, DACVS, professor of equine surgery at École Nationale Vétérinaire de Lyon, France.

“In my opinion, diagnostic analgesia remains the only way to reliably localize the site of pain responsible for lameness,” Dr. Schramme said.

“However, it is crucial to be aware of the limitations of the techniques so clinicians can recognize the potential for false positive and false negative results.”

Subtle or inconsistent lameness

If a horse has subtle or inconsistent 10

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lameness, any gait improvement will be difficult to detect and grade objectively, he explained, adding that a 2010 study by Keegan, et al., showed that agreement among lameness experts is often difficult to achieve.

“In cases of forelimb lameness, there was about 90% agreement,” he said. “Forelimb lameness is easily recognized because of the head nod. In milder cases of lameness, the amount of agreement became significantly less. For cases of mild hindlimb lameness, the chance of agreement among experts was no better than pure chance.”

Inertial sensors represent a marked leap forward in making the lameness and blocking evaluation more objective.

“There are factors that play a role in deciding whether a horse is better after a block,” Dr. Schramme

explained. “Was the horse difficult to inject? Was there owner pressure for a diagnosis? Is it Friday afternoon at 5 o’clock? All of these factors can make a clinician more or less inclined to see an improvement even if there is none, or not see an improvement if there is one.”

With an objective, automated lameness detection device such as inertial sensors, the clinician is better able to detect mild but consistent gait asymmetry that can aid in the use of diagnostic analgesia.

Inaccurate administration of analgesia

If a horse’s lameness has not improved after a block, there are two possible conclusions. The first is that the pain is not originating within the region or synovial structure that was injected, and

the second is that injection was not administered into the area where it was intended.

“This is crucial,” Dr. Schramme said. “The ability to perform an accurate examination often relies on the clinician’s ability to make this distinction.”

Analgesia may end up in places where the clinician did not intend, such as the blood vessels. “We know from the palmar digital nerve block, the abaxial sesamoid nerve block, and the low 4-point nerve block that we should always aspirate before injecting so we can avoid positioning the needle inside the vessel,” Dr. Schramme explained.

A study by Seabaugh, et al., in 2011 showed that when clinicians performed a four-point nerve block with a contrast agent, up to 39% of horses had contrast agent in the digital flexor tendon sheath, and up to 44% of the horses had contrast agent in the fetlock joint.

“Two other recent studies showed that up to 25% of horses had evidence of mepivacaine in the tarsometatarsal joint after a subtarsal nerve block, and up to 38% of horses had contrast agent present in the tarsal sheath,” Dr. Schramme explained. “This is a serious concern.”

For intrasynovial injections, it can be difficult to be certain that local analgesic was placed correctly, so checks must be made to confirm the injection was intrasynovial. Dr. Schramme noted that one of the most accurate methods is to aspirate synovial fluid from the joint or tendon sheath that is being injected. If synovial fluid cannot be aspirated, the clinician cannot be sure that the needle is in the correct position.

“The second way is to note the lack of resistance to the injection until a certain point,” Dr. Schramme said. “When a certain volume has been injected, you get back pressure on the injection. If you release the plunger, you can see the analgesic come back up into the syringe. It’s a reasonable test, but it is no means 100% accurate.”

The only 100% accurate method is through imaging, he explained. If a clinician adds contrast agent to the injection and can get an radiographic or ultrasonographic image of the position of the needle, then there is no doubt that the needle is in the correct position and the block is being performed in the intended cavity.

“A mere lack of resistance to injection is not a valid test for intraarticular or intrasynovial injections,” he said. “Especially not for the upper limb joints where there are several tissue planes, and the skin and joint surfaces offer very little resistance to injection.”

Diffusion of local anesthetic

Diffusion of the local anesthetic solution into adjacent nerves can muddy the diagnostic picture. The clearest example of this an injection of the coffin joint or distal interphalangeal joint in which the palmar pouches of the distal interphalangeal joint fill up to the extent that they are in direct contact with the palmar digital nerve, distal to where that nerve branches to the heel. As a consequence, the distal interphalangeal block will anesthetize other structures in the foot, according to Dr. Schramme.

“Clinicians need to be aware of this potential when using this block,”

Some common misinterpretations of the subjective portion of diagnostic intrasynovial or regional analgesia include: • Inconsistent or insufficient lameness • The clinician is biased by the expected result • Inaccurate regional desensitization following diagnostic analgesia • Inappropriate timing of gait assessment after an analgesic technique • Disease of subchondral bone contributing to joint pain • Abnormal gait caused by mechanical restrictions instead of pain • Lameness caused by pain so severe that it cannot be sufficiently ameliorated by diagnostic analgesic techniques.

Dr. Schramme said. “Be careful not to make false-positive conclusions.”

Another area of concern is the area of the origin of the suspensory ligament, both in the forelimb and the hindlimb. It is known that the palmar pouches of the carpometacarpal joint and the tarsometatarsal joint closely associate with the origin of the suspensory ligament and can even interdigitate with some of the fibers of the origin of the suspensory ligament, so it is not surprising that local anesthetic injected into those joint cavities may have an effect on pathology or pain arising from desmitis of the origin of the suspensory ligament.

“When performing diagnostic analgesia in general, it is crucial that the clinician gives himself or herself a pat on the back—or not, as the case may be,” Dr. Schramme said. “Clinicians must always stay self-critical and question block results.”

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For more information: Keegan KG, Dent EV, Wilson DA, et al. Repeatability of subjective evaluation of lameness in horses. Equine Vet J 2010;42:92-97.

Seabaugh KA, Selberg KT, Valdés-Martínez A, et al. Assessment of the tissue diffusion of anesthetic agent following administration of a low palmar nerve block in horses. J Am Vet Med Assoc 2011;239:1334-1340.

ModernEquineVet.com | Issue 9/2015

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Hematology

Better use of

thromboelastometry Horse blood clots faster than dog or human blood during the test.

M e l i s s a

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U n i v e r s i t y

The blood of horses differs

substantially from that of humans and dogs when the diagnostic tool thromboelastometry is used to assess the status of blood flow and coagulation, according to recent work from researchers at the University of Illinois College of Veterinary Medicine.

Their work should improve clinicians’ ability to use thromboelastometry effectively in the care of critically ill horses.

Factors such as disease, medications and other conditions can affect hemostasis, which is why doctors in both human and veterinary medicine need ways to evaluate the status of this process in the patient.

In horses, common diseases such as colic, colitis, endotoxemia and sepsis are associated with altering the hemostatic pathway,

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I l l i n o i s

leading to coagulation abnormalities in these horses. It is critical in these patients to have the ability to assess their current blood clotting ability for successful treatment.

Recently Maureen McMichael, DVM, MS, PhD, DACVIM, DACVECC, and Pamela Wilkins, DVM, DACVECC, directed a study to further evaluate thromboelastometry for clinical use with horses.

Thromboelastometry is a method that allows kinetic observation, in real time, of clots forming and dissolving.

“There has been very little if any standardization of how this test is conducted,” said Dr. McMichael.

Thromboelastometry is useful for looking at the interaction of coagulation factors, anticoagulant drugs, blood cells and platelets during clotting and fibrinolysis, the breakdown of clots. It uses conditions to mimic the flow of blood in veins to provide more precise results. Unfortunately there have not been dedicated parameters set for methodology and reference ranges in horses for this test.

In the study, Drs. McMichael and Wilkins determined how much of the clotting pathway occurs in citrated equine whole blood, and what effects this has on results of the thromboelastom-

shutterstock/kao

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etry. Citrate is a compound added to blood to prevent clotting from occurring since often the time between taking the blood sample and conducting the test is delayed.

When the time comes to run the test, the blood is recalcified so that it can clot again and be tested. The effect of the holding time, which is how long the sample is actually kept before conducting the test, was also evaluated.

Standards need to be developed for tests we use to check for clotting ability in the blood of our various patients. We need to consider many of the variables that are different for blood from different animals.

The research team found that there were significant increases in the likelihood of the blood to coagulate as the holding period time was lengthened. They also found that there was a significant increase in pro-coagulant factor activity after a 30-minute holding time, and that there was a strong activation of the coagulation pathway during this time.

“Our study shows that horse blood is stimulated to clot much more quickly outside the blood vessels than is the blood of dogs or humans. Horse blood has a very strong contact activation, which may partially explain why very sick horses are prone to clot quickly with some diseases,” Dr. Wilkins said.

The research determined that to achieve the best results for thromboelastometry studies, a profound outside stimulation was needed when using recalcified blood. Without some sort of stimulation, the recalcified blood

"Horse blood has a very strong contact activation, which may partially explain why very sick horses are prone to clot quickly with some diseases."

Dr. Pamela Wilkins

From left: Drs Pamela Wilkins and Maureen McMichael at the equine clinic at the University of Illinois. Their research evaluated thromboelastometry for the clinic use of the test in horses.

Photo courtesy of University of Illinois

should not be used to study the system of hemostasis in horses.

“Our study showed that a strong trigger will help minimize the differences present in many cases,” said Dr. Wilkins.

“We believe we have set a standard to allow comparison across research institutions,” added Dr. McMichael.

Their findings will provide clinicians and researchers with a better set of data for use with this method of testing, resulting in more appropriate treatment and ultimately a better level of care for MeV critical equine patients.

For more information: Rossi TM, Smith SA, McMichael MA, Wilkins PA. Evaluation of contact activation of citrated equine whole blood during storage and effects of contact activation on results of recalcification-initiated thromboelastometry. Am J Vet Res. 2015 76;(2):104-187.

ModernEquineVet.com | Issue 9/2015

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news notes

Traveling through The ARK Advice from equine experts at the Cornell College of Veterinary Medicine will enable The Ark at JFK, a new animal handling facility being built at John F. Kennedy International Airport in New York, to offer traveling horses better, safer and more comfortable accommodations.

But CVM “will not have a clinic at JFK,” said Linda Mittel, DVM, one of the college’s consultants for the project. Instead, the LIFECARE Veterinary Health System will manage the clinic. However, the Cornell University Veterinary Services in Stamford, Conn.,

and Cornell Ruffian Equine Specialists in Belmont, NY, are among the hospitals that may accept animals from The Ark for emergency care.

“They are world-class, state-of-the-art facilities, equipped for round-the-clock care and staffed by talented veterinarians, whose work is informed by the latest in veterinary research,” said Dr. Mittel. “So we will offer high-quality, 24-7 emergency care, but we won't have a clinic at The Ark.” Dr. Mittel said CVM has been primarily a consultant in the design of the large animal section of The Ark, “helping the developer to meet USDA biosecurity requirements and needs specific to the animals, such as air flow, feed storage, stall sizes, heating and AC, and anything else that makes the facility safe and comfortable for the animals.”

The Ark is the world’s first privately owned, 24hour animal airport terminal and quarantine center.

The developer, ARK Development LLC, expects to complete construction in the first quarter of 2016 and commence operations soon after that.

MeV

Photo courtesy of Cornell College of Veterinary Medicine

New study to identify risks of transporting horses

The Cornell College of Veterinary Medicine (CVM) has been doing a great deal of good work for The ARK at JFK, a new animal handling facility at John F. Kennedy International Airport.

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As part of her PhD on the topic of equine transportation, Barbara Paladino and her supervisors at the University of Sidney are distributing a survey to collect data on horse transportation practices and transport-related illnesses in Australia.

Most of the existing research on equine transportation has been conducted in countries outside of Australia, and Ms. Paladino is trying to determine whether the problems arising in Australia could be different to those in Europe.

Australian horse owners, trainers, breeders and organizations are invited to complete an online, 10-minute survey if they have transported horses within the past two years.

“We are particularly interested in any diseases that have occurred to your horses in order to document and investigate underlying potential reasons behind these events. The aim of the study is to gather data to identify transportation risk factors, and therefore potentially make horse transportation safer and less stressful. To achieve this, we need the ‘real world’ input of Australian equine industry members,” she said.

The survey can be accessed at www.surveymonkey.com/r/SM9F9SJ

Stephanie Valberg joins Michigan State Photo courtesy of Michigan State University

“As a clinician scientist, one Stephanie Valberg, DVM, PhD, of the most important parts of has been named the Mary Anne my research is collaboration,” said McPhail Dressage Chair in Equine Dr. Valberg, who has collaborated Sports Medicine in the Department with epidemiologists, nutritionists, of Large Animal Clinical Sciences, geneticists, neurologists, endocriMichigan State University College nologists, biochemists, and physiof Veterinary Medicine. Dr. Valberg ologists.

“The breadth of expertise will join the faculty on Nov. 1, 2015. in the health sciences at MSU will “Dr. Valberg is an international be important to my work—I don’t leader in understanding and manDr. Stephanie Valberg will join the College on always know who I’m going to colaging equine neuromuscular disNovember 1, 2015.

A prolific writer and respected laborate with until we start to get a orders,” said Dan Grooms, DVM, researcher, she has mentored more than 60 research problem.”

PhD, chair of the Department of graduate students, interns, residents, and postDr. Valberg comes to MSU Large Animal Clinical Sciences. doctoral students. from the University of Minnesota “Her experience in establishing College of Veterinary Medicine.

The recipient of numercollaborative relationships with specialists across the ous honors, Dr. Valberg most recently was awarded the health sciences will play an important role in driving the 2014 Richard Hartley Clinical Award from the British research, teaching, and clinical missions of the DepartEquine Veterinary Association for her research linking ment and the College.” seasonal pasture myopathy to box elder tree seeds.

Dr. Valberg’s work in equine muscle disease has transDr. Valberg, who holds four patents, has authored or formed clinical practice. Her neuromuscular research coauthored more than 140 peer-reviewed publications has led to the discovery of previously unknown muscle and 28 book chapters, as well as almost 100 articles in disorders, identification of their genetic basis and the depublications for the general public and has mentored velopment of nutritional strategies to minimize muscle more than 60 graduate students, interns, residents, and pain. She also developed the first feed for horses used to post-doctoral students and is a recipient of numerous treat exertional rhabdomyolysis and was a member of awards for teaching and mentorship. the team that sequenced the equine genome.

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Horses need help when it comes to insect pests like flies,but may are in the dark about the best management for flies, according to a new overview of equine fly management in the Journal of Integrated Pest Management.

One fly-management method that is gaining ground is the use of wasps that are parasitoids of fly pupae. The female wasp inserts eggs into the fly puparium, and when the egg hatches, the wasp larva eats the fly pupa.

The researchers conducted research on two wasp species that are sold commercially to see what type of manure they preferred.

“In the lab, we found that the Muscidifurax species we tested preferred bovine manure, and the Spalangia species preferred equine manure, so there seems to be some sort of differentiation there, which could impact control

on a farm,” said Erika Machtinger, a PhD student at the University of Florida.

Because of this preference, according to the researchers, the ability to identify fly species is important so the correct wasp parasitoid can be used. The authors also provide other advice regarding when the wasps should be released, how often they should be released, and how many should be released.

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Credit: Lyle Buss, University of Florida

Manage flies with wasps instead of pesticides

For more information: Machtinger ET, Geden CJ, Kaufman, House AM. Use of pupal parasitoids as biological control agents of filth flies on equine facilities.

Journal of Integrated Pest Management, September 2015 DOI: 10.1093/jipm/pmv015 ModernEquineVet.com | Issue 9/2015

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news notes

Grayson-Jockey Club Research Foundation Launches Pair of EIPH Projects

Shutterstock/Mikhail Pogosov

Grayson-Jockey Club Research Foundation announced that it is funding two projects aimed at in-depth investigation of the pathophysiology of exercise induced pulmonary hemorrhage (EIPH) and the effect of the medication furosemide on that condition.

The American Association of Equine Practitioners (AAEP) is playing a prominent role in funding the projects, and Grayson-Jockey Club Research Foundation has reached out to racetracks to complete the funding. To date, the following racetracks and companies have pledged financial support at an equal level: Churchill Downs, Del Mar Thoroughbred Club, Keeneland, Kentucky Downs, New York Racing Asso-

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ciation, Oak Tree Racing Association, Oaklawn Park, and The Stronach Group.

The projects are being conducted by Warwick Bayly BVSc, MS, PhD, Washington State University College of Veterinary Medicine, and Heather Knych, DVM, MS, PhD, associate professor at the University of California-Davis College of Veterinary Medicine.

Among objectives is further pursuit of data following preliminary work that indicated the beneficial effect of furosemide (Lasix, Salix) administered 24 hours prior to exercise may be equal to—and in some parameters, better than—furosemide administered at four hours pre-exercise.

Grayson-Jockey Club Research Foundation had put out a call for more science on EIPH and the use of furosemide to try to mitigate its effects. Five proposals were submitted, and these two were selected by a subcommittee of veterinarians and researchers from the foundation’s Research Advisory Committee.

“Studying bleeders and non-bleeders in simulated races in tandem has never been done before,” noted Larry Bramlage, DVM, a member of the GraysonJockey Club Research Foundation board and AAEP Racing Committee.

The two projects will employ similar approaches to test the indications from the preliminary studies and will use two different populations of horses. The projects will use one group of subjects that is composed of active “bleeders” and one group that are not bleeding, in comparable trials.

“Both will use horses on the treadmill, as well as actual racehorses on the track in simulated races out of the gate to gather data,” said Dr. Bramlage. “This covers the spectrum of controlled scientific data collection and real-life competition using Thoroughbred racehorses that are intended to continue racing after the projects are completed. Researchers on both projects will collect physiologic and pharmacologic data.”

Stressing that the research is not narrowly looking at only one question, Dr. Bramlage stated, “These projects present an exceptional opportunity to understand more about EIPH than we have ever known.”

Grayson-Jockey Club Research Foundation is traditionally the nation’s leading source of private funding for equine medical research that benefits all breeds of horses. Since 1983, the foundation has provided more than $22 million to fund 322 projects at 41 universities in North America and overseas. More information can MeV be found at grayson-jockeyclub.org.

OSU Opens Equine Health Center late horses with airborne infectious conditions.

“This new facility greatly enhances our ability to provide premier health care for horses of all ages and disciplines,” said Todd C. Holbrook, DVM, DACVIM, DACVSMR, equine section chief. “We are excited to offer these services to horse owners everywhere.”

"This new facility greatly enhances our ability to provide premier health care for horses of all ages and disciplines."

Dr. Todd Holbrook Ready to serve clients, the OSU equine team consists of board certified veterinary specialists in internal medicine, surgery, radiology and sports medicine and rehabilitation. They offer respiratory analysis using a Dynamic Respiratory Scope that records a horse in real time during rest and exercise. Low level laser therapy is available to treat inflamed muscles and many more services. For more information, visit www.cvhs.okstate.edu.

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Photo courtesy of OSU

Thanks to a $1 million lead gift from the E.L. and Thelma Gaylord Foundation, Oklahoma State University's Center for Veterinary Health Sciences recently opened the Gaylord Center for Excellence in Equine Health. Located adjacent to the equine barn inside OSU’s Veterinary Medical Hospital, the Gaylord Center allows OSU veterinarians the capability to offer horse owners more treatment options.

Newly renovated space created an outpatient service area for equine athletes. A separate overhead door entrance allows sport horses to enter the temperature controlled Gaylord Equine Performance Suite directly from the outside rather than going through the hospital’s large animal clinic entrance. In addition, specialty equipment for regenerative medicine is now centrally located adjacent to the exam area.

The Gaylord Equine Neonatal Care Wing has three enlarged stalls with space for a mare and foal. Each stall is equipped with a half-Dutch door to allow care of critically ill foals while still giving the mare access over the top half of the stall. These stalls also accommodate large breed horses, such as Warmbloods and Draft horses.

Lastly, the isolation area was improved by adding a hoist system to manage horses with infectious neurologic conditions or horses that need full sling support or require assistance standing. The HVAC system was replaced with a system that manages the airspace with negative pressure and specialized filters to safely iso-

Thanks to a generous grant, the Gaylord Center for Excellence in Equine Health can offer horse owners more treatment options. Above: Performing ultrasonography at the facility.

ModernEquineVet.com | Issue 9/2015

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