Equine Ambulatory News New Year Brings Staff Changes, Enhanced

Equine Ambulatory News Spring 2010 • Volume Six - Issue One

New Year Brings Staff Changes, Enhanced Services We hope that you all had a wonderful holiday season and are moving into a bright New Year. We are excited to announce that we now offer digital Coggins. The first time we -per INSIDE form the Coggins test with this new system THIS ISSUE we will take three photographs of your horse and these photos will then be in our system Meet the Team Having three children and a full-time job for years to come. The Coggins papers are in Page 2 can bring many challenges to the table, so color and will display the digital images. We I feel fortunate to have a job that I truly offer digital health certificates as well. Deadly Protozoa enjoy with an extensive and necessary sup- Returns We also would like to announce that port system, both at home and at work. Page 3 Dr. Martha Rasch has joined our service As many of you are aware, veterinary as a full-time clinical instructor. Dr. Rasch The Case of the medicine has been shifting from a male brings with her an interest in three-day Purloined Persimmons dominated profession to one that is female eventing, internal medicine and mules. Page 4 dominated. The veterinary applicant pool Many of you already know Dr. Rasch is heavily weighted toward women these Lameness: A as she spent her intern year with us. For days and this has carried over into equine Debilitating and those of you not familiar with her, you will practice. With this shift has come a need Costly Condition quickly realize what a wonderful addition to adjust to a new way of practice in order Page 6 to the practice she is. to accommodate differing needs. I feel for- Colic: A Dr. Dawna Voelkl is working with the tunate to be a part of the MU Veterinary Quick Response is theriogenology service (reproduction) and Medical Teaching Hospital where I can Demanded will continue to provide assisted reproduc- help to mentor the many women com- Page 8 tive technology for our equine patients. ing through, not just on matters related to the science of managing equine disease, For my own part, I am happy to an- Deworming but also to help them work through the nounce I completed the credentialing pro- Strategies struggles associated with finding balance Page 12 cess for the American Board of Veterinary in their lives. Practitioners, certified in Equine Practice. Alison LaCarrubba, DVM, ABVP My husband and I welcomed our new- (Equine Practice) est daughter, Sophia, to our family in July.

College of Veterinary Medicine • University of Missouri Meet the University of Missouri Equine Ambulatory Team Dr. Alison LaCarrubba, originally from New York, graduated PUBLISHED from the University of Missouri College of Veterinary Medicine ANNUALLY BY in 2001. Alison stayed on at the University to complete an THE EQUINE internship in equine medicine and surgery. After the internship, AMBULATORY she spent a year working in an equine exclusive private practice SECTION with a special interest in reproduction. Alison returned to the OF THE University in July 2003. Although the majority of her time is UNIVERSITY OF spent in the ambulatory truck, she also devotes time to working MISSOURI with the medicine department in the teaching hospital. Alison Dr. Alison LaCarrubba COLLEGE OF recently completed the requirements for certification by the American Board of Veterinary Practitioners in Equine Practice. VETERINARY MEDICINE Dr. Martha Rasch is a clinical instructor at the MU College of VETERINARY Veterinary Medicine and focuses on the equine ambulatory prac- MEDICAL tice. Martha was born in Chicago, Ill., and grew up riding hunt- TEACHING ers and jumpers in St. Louis, Mo. She began to ride in three-day HOSPITAL events in college. After earning a DVM at MU, she completed a rotating equine internship at the University. She then continued on to work as a clinical instructor for the equine ambulatory service. Rasch spends the majority of her time instructing senior veterinary students while traveling to work on horses within the Columbia Mission Statement area. She is particularly interested in wound management as well as Dr. Martha Rasch The mission of our equine critical care in the ambulatory setting. Rasch works closely with the ambulatory service is to provide the highest standard of referral clinicians in the MU Equine Clinic to provide superior care to horses. medical and surgical care to our patients while training Our interns have a special interest in working with horses, and potentially going on the next generation of veterinarians. We feel we are to complete a residency, specializing in either equine medicine or equine surgery. Ev- truly attaining this goal by ery June we welcome a new crop of interns. This year our interns include Drs. Karen working together as a team. Bolton, Brittany Hager and Crystal Lee. Dr. Karen Bolten, intern in equine surgery, medicine and community practice, recently graduated from the Ohio State Univer- sity College of Veterinary Medicine. She grew up in Ohio, com- petitively riding saddleseat on saddlebreds, Arabians, and national show horses. Her medical interests include neurologic, muscle, respiratory, and gastrointestinal diseases in horses. Bolten is con- sidering pursuing a residency in equine internal medicine. Continued on page 3 900 East Campus Drive Veterinary Medical Dr. Karen Bolton Teaching Hospital University of Missouri Columbia, MO 65211 Equine Ambulatory News • Spring 2010 Page 2 Equine Piroplasmosis Found in Missouri Piroplasmosis is an infectious,tick- borne disease that is caused by the protozoa Babesia caballi or Babesia equi. These parasites infect the animal’s red blood cell resulting in the characteristic clinical signs of fever, anemia, weight loss, jaundice and potentially death. The United States has screened all imported horses for piroplasmosis for nearly 30 years. The disease was considered eradicated in 1988. In the last year horses in 11 states, including Missouri, have tested positive for the protozoa. In June 2008, Missouri Animal Research is being conducted to de- In August 2008 officials from the Health officials announced a- con termine the types of ticks that carry Florida Department of Agriculture firmed case of piroplasmosis. After the disease. further testing, another five horses and Consumer Services announced All suspect horses are quarantined were euthanized. In September the they had found a positive animal. The until a diagnosis can be confirmed. Missouri outbreak was considered Florida officials quarantined 25 prem- The only treatment for Piroplasmosis “resolved.” ises and tested more than 200 horses. is a potent chemotherapeutic agent In the end, 20 horses from seven dif- Piroplasmosis has been confirmed that can have serious side effects for ferent premises were euthanized. in 288 horses from a Texas ranch. the individual.

Interns continued from page 2 Dr. Brittany Hager, intern in equine surgery, medicine and community practice, grew up in the St. Louis, Mo., area. She has trained extensively with hunter/jumper trainers locally and nationally and shown her own horses starting with pony hunters and advancing up to high amateur owner jumpers. She graduated from the University of Missouri Veterinary School. After her internship, Brittany plans to obtain specialized training as a radiology resident at a university with advanced imaging modalities for equine athletes. Her ultimate career goal is to work in a sport horse practice that specializes in lameness. Dr. Crystal Lee, intern in equine surgery, medicine and community practice, grew up near Edmonton, Alberta, Canada, and has always been in- volved in the breeding and training of miniature horses, as well as showing Dr. Brittany Hager miniature horses at the international level. She did her undergraduate coursework at the Univer- sity of Alberta, and graduated from the Western College of Veterinary Medicine at the University of Saskatchewan. Lee hopes to pursue a residency in equine surgery before returning to private practice in western Canada.

Dr. Crystal Lee

College of Veterinary Medicine • University of Missouri Page 3 Case Study: Persimmons Can Cause Gastric Impaction Maddy, a 20-year old mixed breed pony, presented to the equine ambulatory service in the fall of 2008 for signs of colic. Maddy’s owner noticed a problem at feeding time. The pony did not come in from the pasture with the other horses as he usually does and was not interested in eating his grain. Un- derstanding that colic can quickly become a very serious problem, Maddy’s owner called the equine ambulatory service as soon as he realized Maddy was acting abnormally. When the ambulatory service ini- tially evaluated Maddy they found that he was laying down, sweating and Veterinary Medical Teaching Hospital turbations in various electrolytes and had an elevated heart rate, which was to pursue further treatment. signs of dehydration and inflamma- 60 beats per minute (normal is 28-40 tion. An ultrasonographic examina- bpm). The pony’s mucous membranes Upon arrival, the pony was paw- tion confirmed distension of the small (gums) were pale pink and tacky with ing and sweating and his heart rate intestine and decreased motility. an increased capillary refill time, indi- remained elevated at 60 bpm. A na- cations of dehydration. sogastric tube was passed again and Maddy was then taken to a stall and this time eight liters of reflux were intravenous fluids were started and he A nasogastric tube was passed and obtained. The rectal examination was lightly sedated in an effort to keep approximately four liters of reflux were confirmed mildly distended small him comfortable while the fluids had obtained so nothing was administered intestine. An abdominal tap was per- time to take effect. via the tube. Rectal palpation revealed formed. This is where a cannula or mildly distended loops of small intes- It can be difficult to differentiate -spe needle is inserted into the abdomen in tine. The veterinarian was concerned cific causes of colic, but it is necessary order to acquire a sample of the fluid that the pony may have a surgical le- to determine if the horse has a surgical that the intestines are bathed in. This sion based on the reflux and the find- lesion or if the cause of colic will re- fluid can provide information regard- ings from the rectal examination. spond to medical therapy. In this situ- ing the health of the intestine and ation our main differential diagnoses Referral to the Veterinary Medical the degree of inflammation present. included a strangulating lesion of the Teaching Hospital was recommended. The fluid obtained from Maddy was small intestine (such as a strangulating Anti-inflammatory medication was within normal limits. Routine blood- lipoma), inflammation of the small in- administered in order to provide pain work was performed and an intrave- testine (anterior enteritis), or obstruc- relief. The anti-inflammatory did little nous catheter was placed to facilitate tion of the small intestine secondary to relieve Maddy’s discomfort and the the administration of intravenous flu- to persimmon fruit ingestion. Horses pony was quickly transported to the ids. The bloodwork revealed mild per- Continued on page 5

Equine Ambulatory News • Spring 2010 Page 4 Persimmons continued from page 4 with surgical lesions will typically not Persimmons: A Real Threat respond to our pain management ef- forts and become increasingly painful and systemically ill without surgery. With a Sweet Solution featured case study. Diagnosing an ob- he persimmon tree is commonly During the next 24-hour period T struction caused by the ingestion of the found throughout the eastern, south- Maddy continued to be mildly inter- persimmon fruit can be challenging. ern and midwestern United States. mittently painful and continued to re- During the summer the tree produces flux through a nasogastric tube, which It is important to examine the a small, round fruit (3–5 cm), which was left in place. His pain level did not stomach using an endoscope to look turns orange when it ripens in the fall. increase, as would be expected with a for the concretion itself. If the concre- As the fruit ripens the flavor changes surgical lesion. On day two of hospi- tion has fragmented it may no longer from bitter to sweet and falls from the talization, gastroscopy was performed be present in the stomach, but may tree. This is when the horses consume to examine Maddy’s stomach. have lodged farther down the gastro- the tasty fruit from the ground. intestinal tract, in the small intestine There was concern regarding per- Unfortunately, persimmon fruit and no longer be visible with the en- simmon fruit ingestion as it was the contains a water-soluble tannin that doscope. Horses with persimmon im- right time of year (fall) and there were polymerizes to form an adhesive co- pactions affecting the small intestine persimmon trees on the farm. Per- agulum when exposed to gastric acid. may respond to medical treatment or simmons are known to cause gastric This coagulum reacts with different may have to go to surgery to have the impactions in horses. No persimmon parts of plant material also ingested obstruction relieved. seeds were seen in Maddy’s stomach. by horses and forms a concretion in The pony was continued on fluid ther- Treatment of persimmon impac- the stomach, which becomes a solid apy, was held off feed, and started on tions involves pain management, lax- mass of grass, hay and the persimmon a medication to improve gastrointesti- ative administration, such as mineral seeds themselves. This concretion in nal motility. oil, and general supportive care (fluid the stomach can irritate and dam- therapy). In 2002, oral administra- After 48 hours Maddy was feeling age the stomach lining, leading to tion of a carbonated cola soft drink much better, was bright and alert and colic and gastric ulcerations. Specifi- resulted in resolution of persimmon was showing interest in food. He was cally, this concretion of plant mate- impactions in human patients. Since weaned from his intravenous fluids rial and persimmon seeds can block that time, treatment of horses with and started back on hay. At this point the stomach outflow resulting in a persimmon impaction utilizing a car- Maddy began passing manure and it gastric impaction, or it can break into bonated cola has been successful. In was noted that he was passing many fragments and cause a blockage of the the future if a persimmon impaction persimmon seeds clumps in his ma- small intestine. nure. We suspect that Maddy did in is confirmed, our medical treatment Clinical signs in a horse with an fact have a small intestinal obstruc- will likely include administration of obstruction associated with persim- tion secondary to persimmon seed a carbonated cola soft drink in order mon seed concretion can vary. Some ingestion, which responded to our to break down the concretion before horses may show intermittent mild medical therapy. a surgical intervention is attempted. to moderate colic signs that continue Maddy was discharged from the despite treatment with anti-inflamma- Although persimmon seed impac- Veterinary Medical Teaching Hospital tory medications and laxatives. Other tions are considered rare, it is an im- and has continued to do well in the horses may present with acute, severe portant differential for a horse with year and half since his colic episode. colic, like the pony mentioned in the colic in the fall in Missouri.

College of Veterinary Medicine • University of Missouri Page 5 Advanced Tools to Diagnose Lameness Look for Common Causes First some questions that may help determine Lameness affects the equine industry any gait/performance inadequacies. more than any other ailment and accounts for $678 million to $1 billion in economic 1. Does my horse bob his/her head while loss each year, five times greater than colic. walking or trotting? Lameness is a symptom manifested by 2. Does my horse appear to be taking an alteration of the normal gait pattern, shorter strides than in the past? which may affect a horse minimally, by 3. Does my horse “point” or hold one reducing performance, or dramatically, by forelimb forward while standing? causing complete inability to ambulate. 4. Is my horse ill-mannered when I Lameness does not discriminate, affecting tack up? horses of all ages, breeds, and disciplines. 5. Is my horse unwilling to move forward A big fear of many horse owners is asking under saddle or refusing jumps? a horse to perform in pain. Therefore, it 6. Is my horse unwilling to flex his neck is important to recognize basic alterations during collection or to either side? in gait pattern and diagnostic/treatment 7. Does my horse work better in one options available so that horse owners direction than the other? can then work with their veterinarians to 8. Is my horse unbalanced in the corners correctly manage their equine athletes. of the arena while under saddle? 9. Does my horse struggle with his/her Lameness Recognition: lead change in the hind end? It can be difficult to recognize lameness in 10. Does my horse appear weak in the your horse. Sometimes having an outside hind end? observer may help. It helps to ask yourself Continued on page 7

Equine Ambulatory News • Spring 2010 Page 6 Lameness physical examination that will include changes of bones and joints surfaces. continued from page 6 observing the animal, obtaining vital Digitalized radiography allows parameters, palpating the entire enlargement and enhancement of Lameness Facts: body with particular attention to the the images taken, which makes them Common things happen commonly. limbs, and applying hoof testers to easier to read. Ultrasound imaging It is easy to find literature online the hooves. Then, the veterinarian allows assessment of soft tissue about diseases or causes of lameness will analyze your horse’s gait. Most structures (tendons, ligaments, that are actually quite rare. These likely, you or an assistant will trot the joint capsules, bursas, etc.) for things often instill fear in a horse horse in a straight line and/or lunge abnormalities. owner that the worst has happened to the horse. Sometimes, this phase of Scintigraphy: A “bone scan” uses their horse. So, instead of thinking the exam will require observation of radioactive material to identify a zebras, let’s think about horses! the horse under saddle. 1. The most common cause of non- region of the body that may be causing weight bearing lameness is a sole Flexion tests or “stress” tests may lameness. These are often recommended abscess and this type of lameness be performed that enhance subtle when lameness is very subtle and can be confused with a fractured lameness so that the veterinarian difficult to localize with a traditional limb. can concentrate on one leg or area. lameness exam and diagnostics. Nerve blocks or joint blocks may be 2. Most lamenesses involve the Traditional and contrast-enhanced necessary to specifically localize the forelimbs. The forelimbs incur CT scans: The use of contrast- area of pain so that further diagnostic much greater concussive forces enhancement in the horse’s leg allows modalities can be aimed at one than the hind limbs because the veterinarian to clearly identify specific site. This will save you money the horse bears 65 percent of its and evaluate subtle soft tissue lesions in the end! weight on the front end. within the foot that may not be 3. Of those forelimb lamenesses, Don’t be surprised if your apparent or accessible with traditional 95 percent occur from the veterinarian completes a neurological imaging modalities (i.e. radiography carpus down. exam in addition to a traditional and ultrasound) and then use CT 4. Of all hind limb lamenesses, 80 lameness exam because some guidance to inject treatment (i.e. percent involve the hock or stifle. lamenesses may be a manifestation of stem cells, platelet-rich plasma, etc.) Highlights of the neurological disorders, such as EPM directly into the lesion of interest. (equine protozoal myeloencephalitis) Traditional therapies and Services through MU: or Wobblers. In-depth lameness exams: Lameness regenerative therapies: Each of these work-ups require a bit of detective Wireless gait analysis: The Lameness therapies uses the body’s own healing work. A thorough history from Locator™ is an inertial sensor-based properties and are often injected into the veterinarian will be obtained. motion analysis system designed at joints, tendons, and ligaments. They Knowledge of your particular equine the University of Missouri as an aid may include steroids, hyaluronic discipline (hunter/jumper/dressage/ to veterinarians for evaluation of acid, stem cells, platelet-rich plasma, cutting/reining/etc.) may be helpful, lameness in horses. The system uses and IRAP among many others that so veterinarian selection may play three small inertial sensors that are may be necessary to heal an injury. attached in a few minutes to the horse’s an important role. The University Advanced treatment techniques: body with tape or Velcro. Data from of Missouri’s ambulatory and in- Treatments include radiograph- the sensors is transmitted wirelessly house clinicians have a working guided farriery services, extra- to a hand-held tablet computer in knowledge and background in a corporeal shock wave therapy, real time. Data processing is fast! variety of disciplines. peripheral limb perfusions, Tildren™ After taking a detailed history, Digital radiography and ultrasound: therapy, and minimally invasive your veterinarian will then perform a Radiographs help veterinarians assess surgeries (i.e. arthroscopy).

College of Veterinary Medicine • University of Missouri Page 7 Colic: An Equine Emergency

pawing the ground, looking at the flank, Colic is a term used to describe the be- sweating, kicking at the abdomen, rolling, havior associated with abdominal pain in lethargy, or lying down for extended pe- horses. It is a symptom of what your horse riods. There may be a reluctance to eat or is experiencing, rather than a specific di- a decrease in manure output. Severe pain agnosis. There are many types of colic, may be accompanied by violent pawing causing symptoms ranging from mild dis- and rolling behavior. comfort to severe unrelenting pain. Severe colic can become life-threatening relative- An adult horse has more than 85 feet of ly quickly, and every case of colic should diverse and tortuous small intestine, large be treated as an emergency. colon, and small colon, which can lead to a variety of gastrointestinal dysfunctions. It is important to know the normal Excessive gas fermentation in the colon behavior of your horse, so that you can can cause distension and pain referred to quickly recognize when something is as gas colic or spasmodic colic. Impactions wrong. Signs of colic include restlessness, lying down and getting up repeatedly, Continued on page 9

Equine Ambulatory News • Spring 2010 Page 8 Colic continued from page 8 Equine Vital Parameters occur as firm masses of feed material hat is ormal that block the intestine. Displace- W N ? ments occur when a segment of the Heart rate – 28-40 beats per minute intestine moves to an abnormal posi- Respiratory rate – 8-20 breaths per minute tion in the abdomen, and volvulus oc- Temperature – 99.5-101.5 degrees F curs when the intestine twists around itself. Strangulation can occur, which keep your horse from doing harm to practices that may reduce the oc- means that the blood supply to the himself or to others. If he is lying qui- currence. Although not realistic for intestine is obstructed. Inflamma- etly, you can let him relax, but if he every horse, the following practices tion of the intestinal wall can also persists in rolling, then walking him are considered ideal for colic pre- result in colic. Sand can accumulate may provide a distraction as long as it vention. At least 60 percent of the in the intestine and cause colic, and can be done safely. daily ration should be forage (either stones called enteroliths can form in hay or pasture), and grain should be Your veterinarian will perform a the colon and cause a blockage. Fat limited. Horses that are overweight physical examination and evaluate tumors called lipomas can form on should wear a grazing muzzle to the severity of the colic. Often times a long stalks, often in older, overweight control weight and intake of rich rectal examination will be performed horses and ponies, causing strangulat- forage, and feeding practices should to discern the cause of colic, such as ing lesions. There are many different be designed to limit intake of dirt gas distension, feed impaction or dis- causes of colic, and the exact cause or sand. Nutritional management placement. A nasogastric tube will be may be very difficult to determine. should be consistent and any feed passed in order to check for intesti- changes should be made gradually. When calling your veterinarian nal fluid backing up into the - stom Turnout and exercise should be pro- about colic it would be useful to be ach or to administer mineral oil and/ vided daily. Clean drinking water able to relay your horse’s vital signs, or water. Pain-relieving drugs and should always be available, and this such as heart rate, respiratory rate fluid therapy may improve comfort, is especially important in the winter and temperature. The gums should gut motility, and the overall systemic months. Using a water heater dur- be pink and moist. In a case of colic, condition of your horse. these parameters may be elevated, ing the winter months may facilitate and the gums may be dry. The veteri- If the colic is severe or is not re- appropriate water consumption. A narian will also want to know details sponding to medical therapy, your regular deworming program should of your horse’s history. Important in- horse may be referred into the Veteri- be maintained. Stress from transport formation to have available are the nary Medical Teaching Hospital for and housing should be minimized. details of previous episodes of colic, further evaluation, which will likely It is said that 70 percent of colics recent changes in management, such include bloodwork, ultrasonographic will recover with minimal to moder- as feed, water, deworming, medica- examination of the abdomen, and ate medical therapy, including moni- tion, or exercise routine, duration of abdominal fluid analysis. Most horses toring and pain control. Twenty per- colic, signs and severity of colic, treat- which are referred to the hospital for cent of colics require intense medical ment that has been attempted, and severe colic have an intravenous cath- therapy including fluids and repeated the response to treatment. Consult eter placed and are started on fluid pain control, and 10 percent require your veterinarian before giving any therapy while complete work-up is colic surgery. Your veterinarian will pain medication. being performed. use the physical examination findings While you are waiting for your vet- It is difficult to prevent many types to determine the level of treatment erinarian to arrive, it is important to of colic, but there are management necessary for your horse.

College of Veterinary Medicine • University of Missouri Page 9 Neurologic Diseases Early Diagnosis, Aggressive Treatment Are Keys to Success

for 24 percent of all cases, which are evenly Neurological disease in horses, al- divided between spinal cord trauma and though not common, can be debilitating traumatic brain injury. Horses with a trau- and dangerous to both horse and owner matic injury to the central nervous system when it does occur. The clinical signs of should be treated early and aggressively to neurological disease in a horse can be var- improve the odds of a positive outcome. ied enough as to present some difficulty in diagnosis. At times it can be difficult to As veterinarians we are taught to “think distinguish between neurological disease rabies first.” Although rabies has been in- and lameness or colic if the horse is down. creasing in incidence over the past few Neurological disease can also present less years, it remains a relatively uncommon dramatically with an abnormality of the cause of neurological disease in the horse. gait, weight loss or muscle wasting. The As rabies is a disease of major public health first step for the veterinarian is to conduct concern, we have to be supremely careful a complete examination of the animal to when dealing with a rabies suspect. There is determine if there are truly deficits affect- no treatment for rabies and it does result in ing the neurological system, and if so, death, so prevention is the key to success. If which part of the nervous system is af- a horse that has been vaccinated for rabies fected and to what degree. is exposed to the disease, the horse should be revaccinated immediately and put un- The most common cause of neurological der observation for 45 days. It is recom- disease in the horse is trauma, accounting Continued on page 11

Equine Ambulatory News • Spring 2010 Page 10 Neurologic continued from page 10 mended that an unvaccinated animal that is exposed be euthanized immediately and tested for the disease in order to limit human exposure. If a human is exposed it is imperative to contact a medical doctor immediately as well as the Missouri Department of Health. Other common diseases affecting the neurologic system of horses include Equine Protozoal Myeloencephalitis(EPM/Opossum disease), cervical vertebral stenotic myeolopathy (Wobblers) and Equine Cervical vertebral instability, or tions include anti-inflammatory ther- Herpes Virus. As many neurological Wobblers is typically seen in younger apy and an invasive surgery that pro- diseases present with similar clinical horses (1–3 years), although certain vides stability of the vertebral column signs it can be very difficult to make a forms can manifest in older horses. by fusing the vertebrae. Typically, the disease affects fast grow- definitive diagnosis. Equine Herpes Virus is a highly ing, large breed horses with a high EPM contagious disease that typically re- is a disease of the central ner- plane of nutrition. In younger horses, sults in respiratory disease similar to vous system caused by a protozoan disease results from compression on influenza and may also cause abor- parasite, Sarcocystis neurona. The life the spinal cord by poorly aligned or tion in pregnant mares. There is a cycle of the organism includes two abnormal vertebrae, while in older mutated form of the virus that results hosts — the opossum (the definitive horses, disease is caused by age-related in neurological disease against which host) and many different intermedi- changes in the soft tissue and boney the commonly used vaccine does not ate hosts, including cats, raccoons, structures (such as arthritis) that com- protect. The horses will often present armadillos, and sea otters. Horses press the cord. Diagnosis of cervical with fever and clinical signs consistent are considered a dead-end host and vertebral instability is based on clini- with neurological disease. Any horse become infected by consuming fecal signs and history, along with radio- suspected of having equine herpes ces from infected oppossums. In the graphs of the horse’s cervical vertebral virus must be isolated immediately. horse, the parasite infects tissues of column and potentially a myelogram. the central nervous system — the Although there is no specific treat- brain, brain stem, and spinal cord When a myelogram is performed ment for the virus, supportive care is — resulting in signs of neurologic the horse is put under general anes- required, which includes anti-inflam- disease. This can be a difficult disease thesia, dye is injected around the spi- matory therapy, fluid therapy and po- to diagnose definitively and most re- nal cord and radiographs are taken. tentially the application of a sling. cently we have been using a test con- Narrowing of the dye column around ducted at the University of California, the cord in a particular area is diag- Neurological disease in horses is not Davis to help in our diagnosis. This is nostic for the disease. Once a horse altogether common, but it does occur a blood test, IFAT, which gives a per- is diagnosed with compressive spinal and it can be devastating to both horse cent likelihood that EPM is the cause cord disease, nutritional management and owner. It is important to treat ear- of illness in a horse with appropriate may be instituted in a young horse in ly and aggressively in order to improve clinical signs. an effort to slow growth. Other op- the chances of a positive outcome.

College of Veterinary Medicine • University of Missouri Page 11 College of Veterinary Medicine University of Missouri 900 East Campus Drive Columbia, MO 65211

College of Veterinary Medicine • University of Missouri Parasite Resistance and Deworming: Please contact the Equine Clinic at the What should we do? have a worm burden high enough to be University of Missouri t has become apparent that there is a I considered dangerous and those animals growing resistance of our common equine College of Veterinary can be dewormed much less frequently. parasites to the current deworming prod- Medicine’s Veterinary In the end, designing a program around ucts on the market. As it stands we do not fecal egg counts will likely save horse own- Medical Teaching have a novel anthelmentic ready to hit the ers money as they will end up deworming Hospital at market any time soon. It seems that best most of their herd less frequently. 573/882-3513 if you approach to address the resistance issue involves targeted deworming. When designing a deworming pro- have questions about gram using fecal egg counts, it is impor- this newsletter or More and more people around the coun- tant to perform the egg count multiple equine health. ty have been including a fecal egg count in times within the first year to determine their deworming strategy. Fecal egg counts which horses carry the highest burden. We involve collecting a small bit of manure, do recommend deworming all foals at 2 which is soaked overnight, centrifuged months of age to address Ascarids (round and examined for eggs. It has been sug- worms) and then performing a fecal egg gested that approximately 20 percent of count subsequent to that. the horses in a particular herd will carry 80 If you have questions or wish to perform a percent of the worm burden. Many of the fecal egg count on your horse, please feel free other animals in the herd will, in fact, not to call and talk to one of our veterinarians.