West Nile and EEE: Selecting the right vaccine. When does efficacy outweigh convenience?

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Vol. 2, Issue 1 2014 www.vet-advantage.com West Nile and EEE: Selecting the right vaccine When does efficacy outweigh convenience?

Or you could just use West NIle-INNOVAtOr Mosquitoes may be small, but as transmitters of West Nile virus, they can cause big problems for your horse. Talk with your veterinarian about WEST NILE-INNOVATOR, the West Nile vaccine that has helped protect more horses than any other. 1 1 Data on file, sales report data from 2001 through October 2012, Zoetis Inc. All trademarks are the property of Zoetis, Inc., its affiliates and/or its licensors. 2013 Zoetis Inc. All rights reserved. EQB13005 WestNileInnovator.com/Horse

Editor Mark Thill mthill@vet-advantage.com Managing Editor Graham Garrison ggarrison@vet-advantage.com Senior Editor Laura Thill lthill@vet-advantage.com Contributing Editor Jennifer Ryan jryan@vet-advantage.com Art Director Brent Cashman bcashman@vet-advantage.com Vice President of Sales & Marketing Rick Boggess rboggess@vet-advantage.com Senior Account Executive Kim Long klong@vet-advantage.com Account Executive Doreen Carpenter dcarpenter@vet-advantage.com Executive Vice President of Business Development Kirk A. Augustine kaugustine@vet-advantage.com Vice President Industry Relations Lorne Elder lelder@vet-advantage.com Sales & Marketing Coordinator Paige Kelly pkelly@vet-advantage.com Circulation Laura Gantert lgantert@vet-advantage.com President & Publisher Chris Kelly ckelly@vet-advantage.com Photography by Sarah Jean Condon Corporate Headquarters 3628 Blakeford Club Dr. Marietta, GA 30062 866-388-8212 phone 866-615-9232 fax 2014 editorial board Kim Allen, Henry Schein Animal Health Spencer Breithaupt, MWI Veterinary Supply Scott Handler, DVM, Patterson Veterinary Jeannie Jeffery, Henry Schein Animal Health Jackie King, AVDA Karen Miller, Midwest Veterinary Supply Clay Cass, Merritt Veterinary Supplies John Ryan, MWI Veterinary Supply Michael Stone, Henry Schein Animal Health Mark Ziller, Animal Health International March/April 2014 www.vet-advantage.com»» West nile and EEE: By Laura Thill West Nile and EEE: Selecting the right vaccine When does efficacy outweigh convenience?»» Tapeworm Tapeworm control Tapeworm diagnosis is difficult, making it especially important to treat horses once or twice a year.»» Fescue: By Jennifer Ryan Grazing Danger Identifying pasture grasses can help avoid fescue toxicosis in pregnant mares pg4 pg8 pg13 Veterinary Advantage magazine Equine edition is published bi-monthly, PO Box 862151, Marietta, GA 30062. Copyright 2014 All rights reserved. Subscriptions: $49.00 per year for individuals; issues are sent free of charge to dealer representatives. If you would like to subscribe or notify us of address changes, please contact us at the above numbers or address. POSTMASTER: Send address changes to Veterinary Advantage, PO Box 862151, Marietta, GA 30062. Please note: The acceptance of advertising or products mentioned by contributing authors does not constitute endorsement by the publisher. Publisher cannot accept responsibility for the correctness of an opinion expressed by contributing authors. Periodicals Postage Paid at Marietta, GA and at additional mailing offices. www.vet-advantage.com equine edition Veterinary advantage ««March/April 2014 3

West Nile and EEE By Laura Thill West Nile and EEE: Selecting the right vaccine Nobody wants to stick it to the horse especially when it comes to needles and vaccines. So, equine veterinarians, such as Kevin Hankins, DVM, MBA, a senior veterinarian in veterinary technical services with Zoetis, appreciate why some horse owners prefer vaccinating their horses with combination vaccines designed to immunize against West Nile virus, Eastern equine encephalomyelitis (EEE), herpes, influenza, tetanus and more all in one injection. The downside of using combination West Nile vaccines, however, is that they stimulate a lower immune response then monovalent West Nile vaccines. It s not that combination West Nile vaccines are not effective, explains Hankins. But, in high-risk situations, we see a stronger immune response when we use a monovalent West Nile vaccine. We have to ask, When does efficacy outweigh convenience? Yes, it s easier to use a single injection, Hankins continues. But, by using a monovalent West Nile vaccine, we see a three- When or four-fold increase in immune response across the board for all manufacturers, he says, citing a recent study he led (summarized in the February 2013 Zoetis Technical Bulletin, Comparative Serologic Responses of Horses Vaccinated with Commercial Equine West Nile Virus Vaccines. ) We knew for some time that a monovalent vaccine would have a greater impact, but we were surprised at just how great it was. Springtime is a key time to vaccinate horses and, as such, a perfect opportunity for distributor sales reps to educate their customers, who can pass along that information to their clients, he points out. It takes time to get the word out to veterinarians, as well as to horse owners, who don t want to inject their horses more than once during a vaccinations series. But given the time and expense horse owners invest in their horses, it makes sense to properly vaccinate them, he adds. does efficacy outweigh convenience? 4 March/April 2014»» Veterinary advantage equine edition www.vet-advantage.com

Still learning West Nile virus is relatively new to the United States, according to Hankins. The disease came to the United States in 1991, and we are still learning how it interacts and reacts with mammals. EEE also keeps researchers on their toes. EEE can be affected by hurricane activity, he says. We usually see an uptick in EEE following hurricane season. And, while the disease is more prevalent in the Southeastern states, it can occur anywhere. A couple of years ago, there was a large outbreak in Maine. Similarly, West Nile virus knows no boundaries. Outbreaks have been reported as far north as Canada, throughout the States and in parts of Mexico, according to Hankins. We tend to see a higher incidence of West Nile during drought conditions, followed by heavy periods of rain, he says. Lakes dry and you end up with shallow, hot, stagnant pools of water. Mosquitoes (including those carrying the West Nile virus) thrive in such environments, particularly as the temperature rises to 87 degrees or higher. And, when heavy rains follow a drought, they tend to help the mosquitoes spread out. While weather conditions are the main predictor of West Nile prevalence, there are other factors associated with the disease as well. Birds are a main feeding source for mosquitoes, says Hankins. When the bird population drops, the mosquitoes look to horses and humans as feeding sources. Alligators, squirrels and other mammals can be a reservoir for disease as well. Although there has been an increase in both West Nile virus and EEE for the past two summers, Hankins can t predict what s in store for the coming years yet another reason why it s so important for horses to be properly vaccinated, he says. Serological responses to West Nile virus Horse owners rely on equine practitioners to recommend and implement vaccine protocols to protect their animals against diseases such as West Nile virus and Eastern equine encephalomyelitis (EEE). A recent study by Kevin Hankins, DVM, MBA, a senior veterinarian in equine veterinary operations with Zoetis, compared serological responses to West Nile virus in 280 horses following vaccination with six different regimens of commercial equine vaccines. Three vaccination regimens involved vaccine formulations with West Nile virus in combination with equine encephalomyelitis viruses (EEE and Western equine encephalomyelitis, or WEE antigens) and tetanus antigens, while three vaccination regimens had the West Nile virus component separated from the EEE, WEE and tetanus antigens. In the study, all vaccines stimulated both primary and anamnestic West Nile virus responses to vaccination. West Nile virus antibody responses were consistently reduced when the West Nile virus component was formulated in combination with EEE, WEE and tetanus antigens compared to similar vaccination regimens where the West Nile virus fraction was concurrently administered with EEE, WEE and tetanus containing vaccines. Therefore, when developing West Nile virus protection protocols, practitioners should consider the implications of lower West Nile virus antibody responses in horses vaccinated with West Nile virus combination vaccines. Source: Zoetis Technical Bulletin, February 2013, Study Report No. 12ETBIOEQ01, Zoetis Inc. Low survival rate Once a horse is infected with West Nile, the disease won t spread, says Hankins. The horse is a dead-end host, he explains. However, if you have a herd of horses in close proximity to a pool infested with mosquitoes, it s more likely for them to be exposed, he adds. Of those horses infected, not all will present clinical signs. Still, the disease can take its toll. Clinical signs of West Nile virus and EEE include loss of appetite, depression, persistent fever (102-103 degrees), weakness or paralysis of limbs, muscle tremors, impaired vision, head tilt or pressing, convulsions, inability to swallow, circling, aimless wandering, hypersensitivity or coma. The overall death rate from West Nile is approximately 30 percent, says Hankins. However, in severe cases, when the horse is down and can t get up, for these horses the death rate increases to 75 percent. Whereas some horses infected with West Nile virus can pull through with good clinical care, that s not the case with EEE, which is associated with a 90 percent death rate and much more severe clinical signs. Very few unvaccinated horses www.vet-advantage.com equine edition Veterinary advantage ««March/April 2014 5

West Nile and EEE survive EEE, and those that do are never the same again. It can cause extremely aggressive damage to the central nervous system, encephalitis or inflammation of brain tissue. So, it s extremely important for people in EEE-prevalent areas to vaccinate their horses. Although no vaccine provides 100 percent protection, it is very rare for properly vaccinated horses to contract clinical signs of West Nile or EEE, he continues. And, if they do, the clinical signs likely will be very mild and usually not life-threatening. Asking the right questions One of the greatest obstacles to vaccine compliance is complacency, says Hankins. Many veterinarians and horse owners become complacent about protecting horses from encephalitic diseases, he says. If they haven t seen the disease, they believe it s not a big problem. Distributor sales reps should convey to veterinarians that diseases such as West Nile virus and EEE are cyclical, he continues. The rate of disease may go down, but that doesn t mean the disease is not present. That said, some of the best questions reps should ask their customers are: Doctor, are you aware that West Nile virus and EEE have been on the rise the last two years? Have you seen the latest research? Are you aware that a monovaccine can provide three or four times the protection as a combination vaccine? Not only is this an important discussion for sales reps to have with their veterinarian customers, it s just as important for veterinarians to educate their clients, Hankins points out. It is very convenient for horse owners to avoid injecting their horses with more than one needle, he says. But, they need to understand that while it may be more difficult to see their horses injected twice, it s definitely worthwhile. West Nile Virus: Leading cause of arbovirus encephalitis West Nile virus is the leading cause of arbovirus encephalitis in horses and humans in the United States, according to the American Association of Equine Practitioners. Since 1999, more than 25,000 cases of West Nile Virus encephalitis have been reported in U.S. horses. Horses represent 96.9 percent of all reported non-human mammalian cases of the disease. West Nile has been identified in all parts of the continental United States, most of Canada and Mexico. Several Central and South American countries have also identified it within their borders. West Nile Virus is primarily transmitted to horses (and humans) by mosquitoes that have fed from infected birds. It is transmitted by many different mosquito species, and this varies geographically, says AAEP. The virus and mosquito host interactions result in regional change in virulence of the virus, and no prediction can be made regarding future trends in local activity of the viruses. West Nile Virus is primarily transmitted to horses (and humans) by mosquitoes that have fed from infected birds. If there s any good news, it s that the virus is not directly contagious from horse to horse or horse to human. What s more, indirect transmission via mosquitoes from infected horses is highly unlikely, as these horses do not circulate a significant amount of virus in their blood, according to the association. Among horses exhibiting clinical signs of West Nile Virus infection, approximately 30 percent will die, many from euthanasia. Data shows that 40 percent of horses that survive the acute illness caused by the virus exhibit residual effects such as gait and behavioral abnormalities six-months post-diagnosis. The AAEP recommends West Nile Virus vaccination as one of its five core vaccines, along with tetanus, rabies, Eastern Equine Encephalomyelitis and Western Equine Encephalomyelitis. (Like West Nile, the last two are primarily mosquito-borne diseases.) 6 March/April 2014»» Veterinary advantage equine edition www.vet-advantage.com

Tapeworm Tapeworm control Tapeworm diagnosis is difficult, making it especially important to treat horses once or twice a year. The best way to identify what product is effective on a given farm and which horses are the highest shedders of parasite eggs is a fecal analysis program, says Wendy Vaala, VMD, Dipl. ACVIM (LA), Senior Equine Technical Service Veterinarian with Merck Animal Health. We still have drugs that work and work very well, Dr. Vaala says. Certain products work better on certain farms in certain areas of the country. Unfortunately, we don t have one drug that works every time in every horse. That s what we no longer have. A properly timed Fecal Egg Count Test (FECT) kit can identify which horses are high shedders or low shedders. In many cases, 10 to 20 percent of adult horses are high shedders, which is where treatment should be focused, FECTs Tapeworms are much more than a nuisance to horses. They present several serious health threats, according to Hoyt Cheramie, DVM, MS, Diplomate, American College of Veterinary Surgeons, and manager, Large Animal Veterinary Services, Merial Ltd. The intermediate host for horse tapeworms (a forage mite) along with the horse s exposure cannot be controlled. For this reason, we must assume horses will be infected and treat them prophylactically once or twice a year (depending on incidence in a particular region), usually in the fall and late spring, he says. says Dr. Vaala. Then, 80 to 90 percent of horses will be low shedders and can receive less treatment. After the initial FECT, Dr. Vaala recommends deworming and performing a second FECT test to determine if there is a reduction in egg count. If the product does not provide the expected reduction in egg counts, then the dewormer used isn t effective on that particular farm. Dr. Vaala cautions veterinarians to price FECTs reasonably within a practice s offerings. Diagnostics, services and knowledge that s a slower sell, but this is a service, she advises. Most horse owners like having an individualized approach to their horse and their farm. They like to know their vet comes on the farm, takes stock of who they are and what they do. 8 March/April 2014»» Veterinary advantage equine edition www.vet-advantage.com

Tapeworm There is no good way to diagnose tapeworms in horses, Cheramie continues. Traditional fecal egg count tests (FECTs) used to detect their eggs in horse feces is considered unreliable, and not finding tapeworm eggs in feces doesn t necessarily prove their absence. Fecal egg counts often are used to evaluate small strongyle levels, and while veterinarians won t see tapeworm eggs, they still should recommend treatment for tapeworms based on regional incidence and risk as part of the control program that will be created based on the strongyle findings, he explains. Research suggests that tapeworm infection rates range from about 12 percent to 96 percent (with an average infection rate of 54 percent), depending on location. So, while veterinarians likely won t see tapeworm eggs on fecal egg count tests, they still should recommend treatment, says Cheramie. The good news is that many veterinarians do, indeed, promote tapeworm treatment for their equine patients, Deworming: timing and management The horse s environment and activities may guide a large part of the veterinarian s deworming recommendation, says Nathan Voris, DVM, MBA, Equine Technical Services Veterinarian with Zoetis. The next step is taking a good look at all the risk factors that are exposing the horse to parasite eggs and trying to address those risk factors through management choices, Voris says. The No. 1 risk factor is the age of the horse. While horses are still young, roundworms remain the most significant parasite threat. Therefore, foals may require more regular treatment. Fortunately, most healthy horses develop some immunity to roundworms over time. The most significant parasite threat for adult horses is the small strongyle. Other factors Voris recommends veterinarians consider are: Number of horses grazing in a pasture or paddock Frequency of movement on and off the farm If horses regularly eat off the ground Indiscriminate pasture rotation Improper manure disposal Immune challenges due to disease, Cushing s disease or insulin resistance Voris says that identifying these risk factors may be helpful to the veterinarian when developing every aspect of a horse s healthcare plan from vaccinations to dental exams. Understanding the entire environment can help reduce unnecessary treatments and increase the overall value of on-farm veterinary visits. notes Cheramie. There has been a shift in parasite management strategies, and veterinarians have become more involved in this than in the recent past, he points out. For sales reps, the time is right to remind their customers to educate their clients on the importance of tapeworm control when discussing parasite control strategies, he adds. The dangers of not treating There are three species of tapeworms known to infect horses in the United States. Anoplocephala magna and Paranoplocephala mamillana are very rare, while Anoplocephala perfoliata a short, yellow/ green parasite with a triangular body and four suckers with which to secure itself to the mucosa of the host pose a risk. Tapeworms require an intermediate host to develop. In the case of the A. perfoliata, mites found in pastures or hay serve as the intermediate host. Typically, there is no seasonal correlation with tapeworm infestation, except during the exposure period, when mites exist in pastures. Within the mite, the tapeworm egg undergoes cellular division and develops into a larva within two to four months. When a grazing horse inadvertently ingests infested mites, within six to 10 weeks the larvae develop into mature adult tapeworms. Equine tapeworms often congregate around the ileocecal valve, located at the junction of the small and large intestine. Inflammation can lead to ileocecal imtussusception lesions or impaction of feed material. In fact, for 50 percent of horses diagnosed with ileocecal impactions in the UK, the condition has been associated with tapeworms, says Cheramie. In addition, horses may suffer from spasmodic 10 March/April 2014»» Veterinary advantage equine edition www.vet-advantage.com

Tapeworm Taking the reins on parasite control Armed with increasingly more information, parasitologists are getting smarter and smarter about combating newly emerging parasites, according to AAEP expert Martin Nielsen, DMV, Ph.D., Dipl. EVPC (chair). Equine veterinarians have relied heavily on anthelmintic treatments in the past. As de-wormers became cheaper, easier to deliver, and available over the counter, they began over-treating, leading to drug resistance. But, that s not the case anymore. Today, more equine veterinarians understand that a parasite is not just a parasite. Over 100 different species can infect the horse, and they are widely different in terms of pathogenicity, life cycle, epidemiology anthelmintic resistance, etc. So, it s necessary to have parasite surveillance in place in order to devise the right treatment recommendations. Clients need information about parasite categories present on their farms and the level of anthelmintic efficacy against them. For distributor sales reps, this is an opportunity to remind their veterinarian customers of the importance of educating their clients and providing surveillance products and advice. Striking a balance The question for many equine veterinarians has become how to determine a healthy balance between treating and over-treating parasite infections, says Nielsen. The AAEP Parasite Control Guidelines state that the goal of parasite control should be to limit infections not eradicate all parasites. This is impossible to do and can result in parasite drug resistance. And, not all horses on a farm require the same control measures or as frequent treatments. For instance, a higher or lower fecal egg count should be considered in the context of the overall health of the herd. To some degree, shedding is normal, according to Nielsen. It comes down to finding the right balance of treatment. Reaching out to customers With the right approach, sales reps can initiate an informative discussion about parasite control with their veterinarian customers. Some good probing questions to ask are: Doctor, what is the level of anthelmintic resistance in your area (particularly with regard to cyathostomins and Parascaris equorum? ) Have you been testing your equine patients? If veterinarians are not testing their patients, they have no way of knowing whether their clients protocol for addressing parasites is or is not working. They can begin by getting their clients to evaluate what they currently are doing to control parasitic infections. If egg count reductions suggest resistance, it will create an opportunity to discuss their de-worming program. Editor s note: For more information, refer to the October 2013 issue of Vet-Advantage Magazine. colic, related to the inflammation and ulcerations of the intestinal lining caused by tapeworm attachment. Depending on the region and the risk of exposure to mites, horses should be treated either once or twice a year for tapeworms. The rep s role Sales reps should remind their equine veterinarian customers to keep tapeworm control in mind when making recommendations to their clients, says Cheramie. For the most part, horse owners and trainers follow though with tapeworm treatment, he notes. Could there be greater compliance? Yes, there are always some horses that are not treated, he points out. That s why it s important for sales reps to have this discussion with their customers who, in turn, should educate their clients. For many years, we over-treated horse parasites, says Cheramie. Veterinarians treated horses as many as six to eight times a year, he explains, and that likely contributed to resistance and decreased drug efficacy. Now that we generally are treating horses less, we must ensure that all components of parasite control are incorporated in treatment plans. We must remember to include tapeworm control. 12 March/April 2014»» Veterinary advantage equine edition www.vet-advantage.com

By Jennifer Ryan Fescue Grazing Danger Identifying pasture grasses can help avoid fescue toxicosis in pregnant mares Thousands of horses graze on up to 12 million estimated acres of tall fescue grass in the United States some of which can be deadly for pregnant mares and their foals. produces an alkaloid that blocks the hormone prolactin. In horses, prolactin affects milk production. Tall fescue is a cool-season grass that greens up in the fall and helps to extend the grazing season. It thrives in Kentucky, Ohio and Missouri, among other states. First planted in the 1950s and 60s for its hardiness and ability to help prevent erosion, a specific variety of the grass called Kentucky-31 is now known to cause a condition called fescue toxicosis in pregnant mares. Fescue toxicosis can cause early embryonic loss, prolonged gestation and interfere with milk production. Knowing if tall fescue is in a pasture can help avoid those losses for owners who want to expand their herd through breeding. Plain fescue itself is okay, but there is a variety called Kentucky-31, which is the majority of fescue found in the U.S., that is infected with a fungus that produces alkaloids that interfere with the mechanisms of milk production among other things, says David Christiansen, DVM, assistant professor at the Mississippi State University College of Veterinary Medicine. It probably wasn t until the 1980s or early 1990s that the disease process was worked out. Kentucky-31 fescue provides a home for a specific fungus, Neotyphodium coenophialum. The grass and fungus have a symbiotic relationship that helps the plant tolerate stressors such as drought or insects. The fungus David Christiansen, DVM Fescue toxicosis also can result in prolonged gestation, which may lead to a difficult birth for mares and often includes retained placentas. Signs of toxicosis A common sign of fescue toxicosis is the complete absence of milk production, notes Melinda Poole O Banion, DVM, Dipl. ABVP, product development manager for equine at Dechra Veterinary Products. Fescue toxicosis also can result in prolonged gestation, which may lead to a difficult birth for mares and often includes retained placentas. A lot of times it s a struggle because the foals are so big and weak and exhausted from the difficult labor, she says. Then, there are the nutritional concerns because there is no milk to feed them, and there is no passive transfer of antibodies from the colostrum. It s a complete spiral of problems. Historically, it was mainly a problem in the Southeast, where this grass is really popular. However, a study in 1999 showed that fescue was prevalent in at least 31 states in the U.S. and that 63 percent of farms tested positive for the endophytic fungus. Identifying the grass in a pasture is the first step to preventing losses, Dr. Christiansen says. A local Extension agent or agronomist can help identify the grass. The first clue that it s in a pasture is early greening. In Mississippi for example, Kentucky-31 will often be one of the few grasses to turn green in late www.vet-advantage.com equine edition Veterinary advantage ««March/April 2014 13

Fescue Horse owners trying to limit the spread of fescue from one pasture to another should be aware that horses themselves can spread the grass s seed, Dr. Christiansen says. fall and early spring. Next, there are tests to confirm the specific variety of fescue present. Three options Once Kentucky-31 is identified in a pasture, owners have three options. First, they can avoid placing a pregnant mare in the affected pasture. Second, they can eliminate the grass and reseed the pasture. Third, they can use domperidone (EQUIDONE Gel) to prevent clinical signs of fescue toxicosis in gestating mares. Limiting access. Kentucky-31 fescue is not a concern for foals themselves or adult horses that aren t pregnant. Only gestating mares are at risk for fescue toxicosis. However, limiting a pasture to only non-pregnant horses requires access to other grazing land or a fescue-free turnout area, Dr. Christiansen notes. If I have a pasture with a significant amount of fescue, I m watching the horses and pulling mares out at least 45 to 60 days before they foal, he says. We have a couple of toxic pastures with yearlings and 2-year-olds grazing. They have not had any trouble. Some research suggests that the fungus found on the fescue can cause horse s veins to constrict, which could potentially cause laminitis. However, Dr. Christiansen says the college s horses have not experienced signs of laminitis. Key points Fescue toxicosis is a concern for late gestation mares grazing on the Kentucky-31 fescue variety The disease may result in increased gestation lengths, no or low milk production and weak foals Mare and foal deaths have occurred due to foaling difficulty caused by fescue toxicosis Gestating mares can be removed from grazing Kentucky-31 fescue pastures 45 to 60 days before foaling Oral administration of domperidone (EQUIDONE Gel) can help prevent signs of fescue toxicosis Reseeding the pasture. Another option is killing the fescue and reseeding with a different grass or non-toxic variety of fescue. But tall fescue is hardy and difficult to remove completely. In fact, Dr. Christiansen notes the grass has spread to several research pastures at Mississippi State University. Agronomists note that it can take multiple applications with a broad-spectrum herbicide to kill it. One of the reasons we like it is because it s so hard to get rid of, he says. Replanting with another variety of fescue can work. We re really mainly concerned with the one variety with a specific fungus that produces the toxins, although problems have been seen with some other varieties. Horse owners trying to limit the spread of fescue from one pasture to another should be aware that horses themselves can spread the grass s seed, Dr. Christiansen says. In addition, the toxins can survive in bales of grass hay. Administering domperidone (EQUI- DONE Gel). The third option is administering domperidone to gestating mares. Domperidone, a D2 dopamine receptor antagonist, increases the mare s prolactin secretion helping to offset the effects of the fescue s alkaloid production. EQUIDONE Gel should be given once daily, starting 10 to 15 days prior to the expected foaling date and continued for five days after foaling, Dr. Poole O Banion says. I recommend using FDA-approved products such as EQUI- DONE Gel for preventing fescue toxicosis and limiting the amount of time a mare is able to graze on the fescue pasture 60 days prior to foaling. 14 March/April 2014»» Veterinary advantage equine edition www.vet-advantage.com

Prevention is the best Protection against clinical signs associated with Fescue toxicosis Fescue toxicosis is caused by the ingestion of an endophytic fungus which infects tall fescue grass. 31 states* and shows more than half of the farms did not realize they had fescue in their pastures. of farms in US tested positive 63% for endophytic fungus. 57% of the positive farms claim to have NO fescue grass. * Participating states in blue 1. Survey of Endophyte Infection and Its Associated Toxin in Pastures Grazed by Horses, B.McCluskey, MS, DVM; J.Truab-Dargatz, MS, DVM; L.Garber, MS, DVM: F.Ross, AAEP Proceedings, Vol. 45, 1999 Pregnant mares grazing fescue may exhibit the following clinical signs: increased gestation lengths tough and thickened placentas agalactia (no or low-level milk production) weak and dysmature foals EQUIDONE Gel is labeled and proven to be 92% effective at preventing clinical signs associated with fescue toxicosis in periparturient mares when administered orally at 1cc/kg 10-15 days prior to expected foaling date and may be continued for up to 5 days post foaling. Side effects of using EQUIDONE Gel may be premature lactation and failure of passive transfer (FPT) of immunoglobulins to the foal. FPT can occur even when mares are not dripping milk. Dechra Veterinary Products 7015 College Blvd., Suite 525, Overland Park, KS 66211 www.dechra-us.com Toll Free (866) 933-2472 2010 Dechra Veterinary Products. All rights reserved.

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