The Modern Equine Vet September 2015

Vol 5 Issue 9 2015www.modernequinevet.comEquine Vet

The Modern

Additional diagnostics can help evaluate carpal sheath effusion

Minimizing the subjective

Dr. Stephanie Valberg to join Michigan State

Distal Phalangeal Bone Lesionsappear early in laminitis

2 Issue 9/2015 | ModernEquineVet.com

TAble of ConTenTS

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

heMATOlOgyBetter use of equine thromboelastometry .................................................................12

NewsTraveling through The Ark ................................................................14New study to identify risk of transplanting horses .................14dr. stephanie Valberg to join Michigan state University 15Manage flies with wasps instead of pesticides ....................15New epph research projects looking for funding .............16OsU opens equine health center ............................................17

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distal phalangeal bone lesions appear early in laminitis

cOVer sTOry:

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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 cen-ter in Kennett Square, pa., which is part of the Univer-sity 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 special-ized vascular channels that extend from the medul-lary 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 chang-es in the distal phalanx, including bone remodeling, medullary inflammation and fibrosis, and vascular le-sions,” she said. “This study further supports a physio-logic and pathologic link between bone and the lamel-lae of the equine foot, and has potential applications regarding laminitis pathogenesis, as well as pain.”

In the study, the researchers reviewed the pathol-ogy in 36 equine front and back hooves taken dur-ing 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 nonper-formance (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 ra-diographic evidence, but micro-computed tomography (cT) and histology showed that some of them had lami-nitis that was not clinically recognized, e.g. “subclinical laminitis,” the study found.

CoVer STory

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appear early in laminitisbone lesions


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The researchers made two bi-axial parasagittal sections of each foot with a bandsaw and took non weight-bearing post mortem ra-diographs of all sections, which were then graded radiographi-cally, grossly and microscopically according to absence or presence of laminitis to separate mild, early laminitis, which might not be ap-parent on radiographs, from more severe cases. The histopathology of lamellar and bone sections were compared with microcT scans to correlate laminitis with distal pha-langeal lesions.

Although this multimodal grad-

ing system standardized variables and enabled detailed pathological summary of the lesions associated with the development and progres-sion of laminitis, this system would not be applicable to clinical medi-cine, Dr. Engiles explained. “How-ever, this system best characterizes laminitis lesions in horses with ei-ther 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 hors-es represented severe, overt and

long-standing laminitis, which was clearly visible on radiographs. The researchers wrote, “Lesions includ-ed severe rotation and displace-ment of the distal phalanx with lamellar wedge formation with la-mellar hyperkeratosis, marked pri-mary epidermal lamellar displace-ment, elongation and distortion.” MicrocT scans and histology of the distal phalanges from severely laminitic feet showed marked dis-tal phalangeal bone loss and re-modeling with severe inflamma-tion, fibrosis and vascular lesions. However, the researchers also found that of 15 feet from eight horses having no history, radio-graphic or gross signs of laminitis, eight feet from five horses had mild acute histological manifestations of laminitis, suggesting subclini-cal disease, and 6/8 feet (75%) had at least one risk factor for lamini-tis. Mild histological findings in these milder or more acute cases included elongation, thinning and aberrant contours of the second-ary epidermal lamellae. Albeit less severe than the changes described above for severe chronic laminitis, according to the researchers, distal phalangeal lesions (porosity, re-modeling, inflammation and early fibrosis) were also identified by microcT and histology in bones from feet with mild or acute lami-nitis. of note, in this particular hos-pital population, the performance horses tended to have orthopedic and sepsis-related risk factors, while the non-performance horses tended to have metabolic/endo-crine risk factors for laminitis.

“Although distal phalanx le-sions were radiographically ap-parent in severe/chronic laminitis, microcT and histology revealed changes that were not radiograph-ically apparent in mild/acute lam-initic feet,” the researchers wrote.

“Typically, distal phalangeal le-sions are not recognized until lam-initis is severe and long-standing,” Dr. Engiles said. “commonly rec-

Figure legendcomposite 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.

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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ognized lesions include remodel-ing and fractures of the solar mar-gin, or ‘tip’ of the distal phalanx. Standard radiography is not sensi-tive 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 inflamma-tion, neoplasia or hemodynamic alterations including bone marrow edema, infarcts and neovascular-ization is especially painful, she explained. “If the distal phalan-geal lesions identified in this study contribute to activation and sensi-tization 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 simi-larities to complex regional pain syndrome,” Dr. Engiles said.

“If it is indeed the case, then this research may also provide ad-ditional therapeutic opportunities for laminitic horses. For example, bone pain in humans and in ani-mal 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 pro-cess, much earlier than previously recognized. The lesions in the bone could significantly contribute to pain associated with laminitis as well as progression of lamellar le-sions 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 reso-nance imaging in live animals, she added, which could lead to earlier intervention and lessen the sever-ity of the disease. MeV


orThopeDiCS

Veterinarians can alter how they evaluate horses with carpal sheath effusion to accurately de-termine and treat the underlying cause, according to researchers at the University of Wisconsin School of Veterinary Medicine.

Although it’s not a common is-sue, 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 per-formance.

Frustrating endeavors Diagnosing the cause of carpal sheath effusion and predicting how well it will heal are notoriously frustrating endeavors for veterinar-ians. While the bulk of published research points toward bone in-juries as the root of the problem,

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 Jor-gensen, DVM a boarded equine internal medicine veterinarian and associate professor of comparative biosciences at the School of Veteri-nary 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 car-pal sheath effusion.”

observations also led Drs. Jor-gensen and Genovese to believe that older, less athletic horses were

Phot

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Additional diagnostics can help evaluate

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.

carPal SHeatH eFFuSionB 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

ModernEquineVet.com | Issue 9/2015 9

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 epide-miology at the school of veterinary medicine, and Matthew Stewart, phD, MVet, bVSc, associate pro-fessor in the college of Veterinary Medicine at the University of Illi-nois, to put their theories to the test.

The team gathered and ana-lyzed clinical records, radiographs and ultrasonographic findings for 121 horses, patients at cleveland Equine clinic, where Dr. Geno-vese now practices, and the for-mer 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

8% of cases in the study, suggest-ing that the current scientific liter-ature vastly overrepresents under-lying 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 struc-tures. The worst injuries extended into structures above the carpus, an area that is often overlooked.

based on their findings, the re-searchers recommend that horses di-agnosed with carpal sheath effusion continue to be evaluated by radiol-ogy to rule out bone involvement. perhaps most critically, the study suggests that evaluations should also include an extensive ultraso-nographic examination of the back of the forelimb from the level of the mid-radius to the fetlock. Special at-tention should be paid to the superfi-cial digital flexor muscle, deep digital flexor muscle and accessory ligament of the superficial digital flexor ten-don, areas where the study found injuries to be most common.

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

The researchers recommended that

horses diagnosed with carpal sheath effusion continue

to be evaluated by radiology to rule out bone involvement.

Jorgensen JS, Genovese RL, Döpfer D, Stewart MC. Musculoskeletal lesions and lameness in 121 horses with carpal sheath effusion (1999-2010). Veterinary Radiology & Ultrasound 2015;56(3):307-316. http://onlinelibrary.wiley.com/doi/10.1111/vru.12241/abstract


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orThopeDiCS

The difficulty with subjective assessment lies in the very defini-tion of the word “subjective.” Errors in judgement, biases, or missed nu-ances can lead to a misdiagnosis or direct the clinician to administer problematic treatment, according to Michael Schramme, DrMedVet, certEo, phD, DEcVS, DAcVS, pro-fessor of equine surgery at École Na-tionale Vétérinaire de Lyon, France.

“In my opinion, diagnostic anal-gesia 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 lamenessIf a horse has subtle or inconsistent

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

“In cases of forelimb lameness, there was about 90% agreement,” he said. “Forelimb lameness is eas-ily 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 evalu-ation 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 after-noon at 5 o’clock? All of these fac-tors 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 con-sistent gait asymmetry that can aid in the use of diagnostic analgesia.

Inaccurate administration of analgesiaIf a horse’s lameness has not im-proved after a block, there are two possible conclusions. The first is that the pain is not originat-ing within the region or synovial structure that was injected, and

Minimizing the

SubjectivePotential Mistakes in Diagnostic Analgesia

B y p a u l B a s i l i o

Photo courtesy of Equinosis (Lameness Locator) • www.equinosis.com


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 ac-curate 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 position-ing 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 tarsometatar-sal 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 seri-ous concern.”

For intrasynovial injections, it can be difficult to be certain that local analgesic was placed cor-rectly, 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 meth-od is through imaging, he ex-plained. If a clinician adds con-trast agent to the injection and can get an radiographic or ultrasono-graphic image of the position of the needle, then there is no doubt that the needle is in the correct po-sition and the block is being per-formed in the intended cavity.

“A mere lack of resistance to injection is not a valid test for in-traarticular or intrasynovial injec-tions,” 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 anestheticDiffusion of the local anesthetic solution into adjacent nerves can muddy the diagnostic picture. The clearest example of this an injec-tion of the coffin joint or distal interphalangeal joint in which the palmar pouches of the distal inter-phalangeal 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 anesthe-tize other structures in the foot, ac-cording to Dr. Schramme.

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

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 carpometa-carpal joint and the tarsometatar-sal 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 in-jected 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 re-sults.” MeV

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.


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.

The blood of horses differs substantially from that of humans and dogs when the diagnostic tool thromboelastometry is used to as-sess the status of blood flow and coagulation, according to recent work from researchers at the Uni-versity of Illinois college of Veteri-nary Medicine.

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

Factors such as disease, medi-cations and other conditions can affect hemostasis, which is why doctors in both human and veteri-nary medicine need ways to evalu-ate the status of this process in the patient.

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

leading to coagulation abnormali-ties 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 McMi-chael, DVM, MS, phD, DAcVIM, DAcVEcc, and Pamela Wilkins, DVM, DAcVEcc, directed a study to further evaluate thromboelas-tometry for clinical use with horses.

Thromboelastometry is a meth-od 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 con-ditions 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 oc-curs in citrated equine whole blood, and what effects this has on results of the thromboelastom-

Better use of

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

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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.


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 path-way 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 recalci-fied blood. Without some sort of stimulation, the recalcified blood

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

“our study showed that a strong trigger will help minimize the dif-ferences present in many cases,” said Dr. Wilkins.

“We believe we have set a stan-dard 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 critical equine patients. MeV

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

"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


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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.,

traveling through the arK

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.

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 tal-ented 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 consul-tant in the design of the large animal section of The Ark, “helping the developer to meet USDA biosecu-rity 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, 24-hour 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

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new study to identify risks of transporting horsesAs 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, DVM, phD, has been named the Mary Anne McPhail Dressage chair in Equine Sports Medicine in the Department of Large Animal clinical Sciences, Michigan State University college of Veterinary Medicine. Dr. Valberg will join the faculty on Nov. 1, 2015.

“Dr. Valberg is an international leader in understanding and man-aging equine neuromuscular dis-orders,” said Dan Grooms, DVM, phD, chair of the Department of Large Animal clinical Sciences. “Her experience in establishing collaborative relationships with specialists across the health sciences will play an important role in driving the research, teaching, and clinical missions of the Depart-ment and the college.”

Dr. Valberg’s work in equine muscle disease has trans-formed clinical practice. Her neuromuscular research has led to the discovery of previously unknown muscle disorders, identification of their genetic basis and the de-velopment of nutritional strategies to minimize muscle pain. She also developed the first feed for horses used to treat exertional rhabdomyolysis and was a member of the team that sequenced the equine genome.

“As a clinician scientist, one of the most important parts of my research is collaboration,” said Dr. Valberg, who has collaborated with epidemiologists, nutritionists, geneticists, neurologists, endocri-nologists, biochemists, and physi-ologists. “The breadth of expertise in the health sciences at MSU will be important to my work—I don’t always know who I’m going to col-laborate with until we start to get a research problem.”

Dr. Valberg comes to MSU from the University of Minnesota

college of Veterinary Medicine. The recipient of numer-ous honors, Dr. Valberg most recently was awarded the 2014 richard Hartley clinical Award from the british Equine Veterinary Association for her research linking seasonal pasture myopathy to box elder tree seeds.

Dr. Valberg, who holds four patents, has authored or coauthored more than 140 peer-reviewed publications and 28 book chapters, as well as almost 100 articles in publications for the general public and has mentored more than 60 graduate students, interns, residents, and post-doctoral students and is a recipient of numerous awards for teaching and mentorship. MeV

Stephanie valberg joins Michigan State

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dr. Stephanie valberg will join the college on november 1, 2015. a prolific writer and respected researcher, she has mentored more than 60 graduate students, interns, residents, and post-doctoral students.

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 spe-cies 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 spe-cies 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 Univer-sity of Florida.

because of this preference, according to the researchers, the ability to identify fly species is important so the correct wasp para-sitoid 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. MeV

Manage flies with wasps instead of pesticides

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


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Grayson-Jockey club research Foundation announced that it is funding two projects aimed at in-depth in-vestigation 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 Foun-dation has reached out to racetracks to complete the funding. To date, the following racetracks and com-panies have pledged financial support at an equal level: churchill Downs, Del Mar Thoroughbred club, Keeneland, Kentucky Downs, New york racing Asso-

grayson-Jockey club research Foundation launches Pair of eiPH Projects

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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 fu-rosemide to try to mitigate its effects. Five proposals were submitted, and these two were selected by a sub-committee 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 Grayson-Jockey 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 proj-ects 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 col-lection and real-life competition using Thorough-bred 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 proj-ects present an exceptional opportunity to understand more about EIpH than we have ever known.”

Grayson-Jockey club research Foundation is tradi-tionally 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 be found at grayson-jockeyclub.org. MeV


Thanks to a $1 million lead gift from the E.L. and Thelma Gaylord Foundation, oklahoma State Univer-sity'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 cen-ter allows oSU veterinarians the capability to offer horse owners more treatment options.

Newly renovated space created an outpatient ser-vice 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 hospi-tal’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 accom-modate 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 neuro-logic 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-

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.”

ready to serve clients, the oSU equine team con-sists of board certified veterinary specialists in inter-nal 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. MeV

oSu opens equine Health center

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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.

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

Dr. Todd Holbrook

reach your veterinarians wherever they are, whenever they want.

FOr AdVerTIsINg rATes ANd INFOrMATION, eMAIlMatthew todd

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The Modern Equine Vet September 2015