iStock photoWork with your veterinarian to develop a clear plan for handling after-hours medical emergencies, including signs that warrant immediate care. Discuss preferred communication methods, expected response times, and backup providers for if your vet is unavailable. In this excerpt from Ask TheHorse Live, Stacey Cordivano, DVM, IVCA, of Clay Creek Equine Veterinary Services, in Chester County, Pennsylvania describes why knowing what to doand who to callcan make all the difference in a crisis.This podcast is an excerpt of ourAsk TheHorse Live Q&A, Planning for Equine Emergencies. Listen to thefull recording here.About the Expert: Stacey Cordivano, DVM, IVCAStacey Cordivano, DVM, ICVA, is the co-owner of Clay Creek Equine Veterinary Services, in Chester County, Pennsylvania, and host of The Whole Veterinarian Podcast. She also co-founded the Sustainability in Equine Practice Seminar series and is a managing partner of Decade One. Both organizations focus on making a positive impact in the equine veterinary community. Cordivano is active in the AAEP as a speaker and committee member. She lives in Pennsylvania with her husband, two sons, and a farm full of animals. Connect with her on Instagram @thewholeveterinarian.

Having a professional regularly assess your horses saddle fit can improve his performance and welfare. | iStockSure, you know your horses unique shape. Youve chosen a tree and gullet width, wither clearance, panel contact, and balance that suit his frameand a seat size to fit you. But even with that effort, does your saddle truly fit?Expert saddle fittingan evolving field rooted in equine anatomy, physics, and biomechanicscan help owners ensure saddles fit their horses properly. Researchers learn more every year, and their findings are transforming what we thought we knew about saddle fit. Here are some of the latest insights shaping the future of equine comfort and performance.Good Saddle Fit: A Responsibility to the HorseKathryn Nankervis, SFHEA, CVPM, associate professor at The Equine Therapy Centre at Hartpury College and University, in Gloucester, the U.K., says we have an important ethical obligation to ensure that the animal we care for is comfortable and unrestricted in movement as much as possible.That means matching saddles to the horses body and looking beyond the back. Poor saddle fit can lead to tissue damage in the back, neck, and limbs as horses adjust their movement to cope, says Jorn Cheney, PhD, at the University of Southampton, in the U.K. Behavior matters, too. If the horse is unhappy with the fit, thats something we definitely dont want, Cheney says.So how do you know if a saddle really fits? Call in a qualified saddle fitting professional, says Nankervis. Coaches and trainers might check a saddle, but they dont typically have the specialized training needed for a full assessment.Assessment is really thorough, and it takes quite a long time, and there are a lot of components and skill involved, Nankervis says. We cant assume that just because people have been in the industry a long time, that theyve picked up this knowledge.Catherine Baker, president and research committee chair of the Society of Master Saddlers in Suffolk, U.K., says master saddle fitters are trained professionals who use a wide range of criteria to evaluate saddle fit.This growing field, based mainly in the U.K., gives horse owners the chance to apply science-backed knowledge to the complex, shifting architecture of tack we place on our horses.Saddle Fitting for Horse Health, Welfare, and PerformanceMore than one-third of riding horses experience back pain, Cheney says, with poor saddle fit as a leading cause.But the benefits of good saddle fit go beyond preventing pain. Its not just a danger if you get it wrong, says Nankervis. There are massive benefits if you actually get it right.Even so, theres some nuance. Nankervis says horses in intense training, working at upper levels, or carrying heavy loads should have custom saddles. Cheney adds that while he considers regular checks and reflocking of saddle panels ideal, especially for sport horses, more research will help determine how much variation leisure horses can tolerate. We dont know what the effects of a subideal configuration are, he says.Testing Saddle Fit on a Moving HorsePeople often assess saddle fit while the horse stands stillbut thats not how horses spend their time under saddle. Movement changes the horses back, and saddle fit needs to reflect that.Cheney explains that although horses spinal columns stay relatively stable during movementthanks to tight joints and thin discstheir back muscles do not. His team used an array of cameras in a recent study and found that horses backs flatten significantly during walking and trotting. Theyre still analyzing data from the canter.This confirms earlier research showing that poorly fitting saddles could damage the longissimus dorsi and epaxial muscles along the topline. Horses might experience pain, decreased mobility, spinal stiffness, and hair loss or skin injuries from rubbing, and they might be shorter-strided.Saddle fitters should focus on parts of the horses back that stay consistent between standing and movement, Cheney says, and add padding in areas that shift. Thats what were targeting, he says. We dont need an overengineered saddle; the goal is really a simple one. Were hoping that by being aware and being able to quantify shape when a horse is moving, we can move towards an optimal configuration where the horse is comfortable all the time.Checking Saddle Fit as Horses ChangeHorses backs changeand often more than we expect. As horses age, have changes in work, or face health issues, their bodies adapt. Muscle mass can increase or decrease, and seasonal factors including diet, illness, and exercise affect body shape.We know from plenty of earlier studies that we cannot design one saddle that perfectly fits the animal throughout its entire life, or even just a year, because the horse can completely change shape, Cheney says.Thats why ongoing assessment matters. Get the fit checked twice a yearor more often if your horse is recovering from illness or injury or experiencing major changes in training or workload. Its not about replacing saddles but tweaking their fit to keep pace with body changes.Saddle fit is a transient thing, isnt it? says Nankervis. Youre striving for the most optimal fit most of the time. But we have to accept that horses do change. So you can have a bespoke saddle for a horse, and stuff changes, and its no longer all that bespoke. Just because you had it fitted once really doesnt mean it stays fitted.Getting Viewpoints from All Your Equine ProfessionalsSaddle fit affects horse health, performance, and welfare. So naturally, it falls into the domain of multiple professionals, says Nankervis. The veterinarian, farrier, dentist, physio (physical therapist), coach, trainer, and saddle fitter all contribute to the bigger picture.If were trying to support horse owners effectively so they can do the best for their horses, and get the best out of their horses, these people should be communicating with each other, capturing the whole picture of whats going on, she says.And each of them brings a unique perspective. What can we do to better understand each others roles, so that we can better serve the horse? she asks.Take-Home MessageEvery horses back is unique and always changing. And so is the science behind saddle fitting. With research and insight from trained professionals, we can do more than guess. We can give our horses saddles that truly fitsupporting health, comfort, and long-term performance.

Horse hair offers insights into health, genetics, stress, and even historyBeyond the aesthetic appeal, horses hair contains information about their health, welfare, breeding, drug intake, and even ancient history. | Adobe stockThat sleek, shiny coat. That thick, flowing mane. The full, elegant tail.We love horses hairso much so that throughout the past 5,000 years weve bred horses based on their coat/hair color and quality. And long before that, humanity began portraying the beauty of equine hair in drawings, paintings, sculptures, animations, and other artwork.Beyond that aesthetic appeal, horses hair contains abundant information about their health, welfare, breeding, drug intake, and even ancient history.In this article well provide an overview of the latest knowledge about what horses hair can tell us.Whats in a Strand of Hair?Hair forms at the bulb, nestled in the follicle under the skin, and grows into a multilayered root thatunless its whiteis colored by melanin. The shaft extends beyond the skin and progressively moves outward as the bulb produces new growth. There, polypeptide chains of amino acids such as glutamic acid, cysteine, and serine create strong keratin fibers that align to create a thick central cortex (sometimes surrounding a thin core called the medulla) and an outer cuticle level where fibers overlap like scales.1Hair consists mainly of keratin, water, melanin pigments, lipidssuch as triglycerides, phospholipids, and cholesteroland minerals, including iron, magnesium, zinc, and copper. Its chemical makeup is 45% carbon, 28% oxygen, 15% nitrogen, 7% hydrogen, and 5% sulfur.Researchers have suggested equine coat hair usually matches human hair in thickness, while tail hair measures about 50% thicker and mane hair falls somewhere between. Horse hair offers strength, resilience, and natural water resistance.2Appearance: A Simple Health Measure in HorsesA good look at a horses coat, mane, and tail can give basic insights into health status, says Carissa Wickens, PhD, associate professor and extension equine specialist at the University of Florida (UF), in Gainesville.Healthy horses usually have glossy coats that follow clear seasonal patterns of winter fullness and summer sleekness. The coat will have some sheen to it when the animal is receiving adequate nutrition, preventative health care, and regular grooming, she says.Horses with compromised immune systems due to internal disease or malnutrition, however, might grow dull or brittle hair. The coat can sometimes get patchy due to skin infections, including rain rot or ringworm, or to parasites such as lice. Hair that doesnt shed, sheds unevenly, or changes color in an unusual way could reflect metabolic disease, such as pituitary pars intermedia dysfunction (PPID, formerly equine Cushings disease).Coat quality can also diminish with prolonged exposure to flies, mosquitoes, and other biting insects, such as Culicoides, especially in hot, humid climates with long insect seasons, Wickens says. It doesnt necessarily indicate a serious health condition or immediate welfare concern, but maintaining skin and coat health requires attention and management, like applying repellents, fly sheets, and masks, using fans, and adjusting turnout schedules to minimize exposure. In addition to discomfort and unsightliness, bites can put horses at risk for bacterial infections, other pathogens (among them West Nile virus), and sarcoids.Beyond the body coat, the mane and tail can also provide health clues when horses rub them off, she adds. Balding manes suggest itchy dermatitis conditions such as insect bite hypersensitivity (IBH), whereas broken hairs around the tailbone can point to scratching due to intestinal parasites. Hair loss along the mane and tail can also signal selenium overdose.But even healthy hair can alert owners to potential problems. For example, splashed white and overo Paint Horses are more likely to carry the EDNBR gene mutation that causes hearing loss and overo lethal white syndrome, Wickens says. Silver coats are often associated with multiple congenital ocular anomalies (MCOA). And some horses with Appaloosa spotting could have night blindness or recurrent uveitis.Chestnut horses have the MC1R redhead gene that researchers have linked to lower pain thresholds, which couldif these horses are not managed correctlylead to behavior problems. Importantly, though, that doesnt mean red coats signal a difficult horse, says Andy Booth, a science-based trainer who works out of southwestern France. I find the chestnut mare reputation to be unfounded, he says. But it can have a strong placebo effect. Once someone decides a horse is difficult, thats how (the horse) tends to be.Finally, a coat that feels warm to the touch doesnt always keep the horse warm, says Grete H.M. Jrgensen, PhD, of the Norwegian Institute of Bioeconomy Research, in Tjtta. In fact, Warmbloods usually have higher coat temperatures in winter than draft horses with thick hair because the coat is not organized in layers with underwool and long cover hairs commonly found in the cold-blood breeds. Such structures in a horses coat are important to protect against the elements and reduce heat loss from the body to the surroundings.Whats in a Whorl?Whorls appear to share the same genomic regions that code for neurologic and behavioral functions. | Adobe stockSwirling hair patterns on a horses head and neckknown as whorlsappear to share the same genomic regions that code for neurologic and behavioral functions, suggesting a genetic-biological link between whorls and temperament says Gregrio Miguel Ferreira de Camargo, PhD, of the Federal University of Bahia, in Brazil.3 In fact, genes linked to whorl position (above, at, or below eye level) have parallels in humans associated with schizophrenia, depression, and Parkinsons disease.Such findings might explain why many people consider horses with above-the-eye whorls to be difficult, those with below-the-eye whorls to be calm and steady, and those with whorls at the eye-line to be somewhere between. In addition, donkeys generally have whorls far down the nose, which aligns with their reputation for being less reactive than most horses, says Katrina Merkies, PhD, a professor at the University of Guelph, in Ontario, Canada.Meanwhile, researchers on multiple studies over the past 15 years have suggested horses with clockwise-swirling whorls tend to favor their right side while those with counterclockwise whorls more often favor their left. Even so, not all research supports such links between whorls and laterality, says Uta Knig von Borstel, PhD, a professor at the University of Giessen, in Germany.Additional work might also help equine researchers link whorls to horses performance traits and the propensity for certain disciplines, such as jumping versus dressage, Ferreira de Camargo says.Monitoring Stress and WelfareWhen horses produce increased levels of the stress hormone known as cortisol, it suggests they might be experiencing welfare issues, says Kristna Machov, PhD, professor in the Department of Husbandry and Ethology of Animals at Czech University of Life Sciences Prague, in the Czech Republic.Salivary cortisol concentrations can give immediate feedback about short-term acute stress, including healthy physical activity, whereas blood and fecal cortisol levels provide insight over the past several hours or days. Cortisol levels in hair, meanwhile, offer a noninvasive way to assess stress and welfare over weeks and months, Machov says.In her teams recent study on hair cortisol concentrations in equine-assisted therapy horses, for instance, they revealed animals didnt benefit from one-month holidays each year, she says. Rather, they showed much healthier cortisol readings when they had three days off each week instead of two.That said, cortisol concentrations can depend on the type of hair (coat, mane, tail), its location on the body, color, and the season in which it was collected. Also, if stress continues for too long, horses stop producing cortisol altogether.Its a very useful parameter that can give the owner an indication of how his horse is doing and, if the level is high, give him an incentive to look for the cause, whether it is related to training or health, for example, Machov says. But its also always a good idea to combine the assessment of physiological parameters with behavioral observation and thorough questioning.Mineral Analysis? Science Says NoSome companies offer hair screening for minerals using advanced techniques such as inductively coupled plasma mass spectrometry (ICP-MS), particle-induced X ray emission (PIXE), and inductively coupled plasma optical emission spectroscopy (ICP-OES). But researchers havent shown their merit.In 2022 scientists at Leipzig University, in Germany, found dramatically different results between laboratories on selenium, iron, copper, zinc, and other mineral concentrations in the same four horses mane hairs.4 That same year Dutch researchers discovered that hair analyses of minerals in cadaver horses did not match their liver biopsiesa highly invasive gold standard for assessing trace minerals. The mineral list included arsenic, cadmium, chromium, cobalt, copper, iron, lead, manganese, molybdenum, nickel, selenium, vanadium, and zinc. Our results do not support the use of hair to determine mineral status in the horse, they reported.5Still, scientists in Poland found that mane analyses gave an accurate reflection of the amount of copper and zinc added to horses oats, suggesting hair could be useful for at least monitoring these two heavy metals. In their 2022 study they also revealed that mane analyses could flag toxic concentrations6 of two dangerous heavy metalslead and cadmiumwhich horses could pick up from their surroundings.As with cortisol concentrations, elements found in hair can vary according to hair type, color, and location on the bodymeaning if youre tracking changes over time, make sure youre comparing like samples.If tracking changes in a horse over time, sample the same type of hair (i.e., if youve tested mane, dont switch to tail hairs). | Adobe stock Long-Window Drug DetectionOfficials at competitive events generally test equine athletes for doping by analyzing blood and/or urine samples. These biological matrices allow for the detection of drugs administered within the previous hours or daysrevealing whether a horses performance has been illegally enhanced for a race or competition, says Ludovic Bailly-Chouriberry, PhD, director of LCH Laboratory, in Verrires le Buisson, France.By contrast, hair offers a critical long-term window for drug detection, says Bob Gray, MSc, chief scientist at LGC Group, in Fordham, England. Because hair accumulates traces of most types of doping agents, it can provide a valuable and reliable record of drug intake over the previous weeks, months, and even years. Considering an approximate mane hair growth rate of 2 cm per month, labs can use high-sensitivity instrumentation such as triple-quadrupole mass spectrometers (MS/MS) or high-resolution mass spectrometry (HRMS) to trace past drug use and even estimate when and for how long the horse was treated, he says.Another important benefit of drug testing in hair is it allows for knowledge and technology to catch up with innovative illegal drug use. Sometimes a gap exists between when people start using a new doping agent and when authorities detect it and scientists develop tests. Long manes and tails keep records of that agents use well after it isnt new anymoremeaning laboratories can analyze the relevant hair sections to detect doping retroactively, says Bailly-Chouriberry.Regardless, pinpointing exact doses and dates through hair analyses remains difficult, so scientists have not yet established cutoff values for drugs allowed within a few days prior to competition, he adds. Plus, drugs get processed on different timescales in the body depending on administration routeorally, topically, or via various methods of injection. Therefore, laboratories focus hair analyses on banned substances such as anabolic steroids, whereas blood and urine analyses remain vital for controlled medications such as the non-steroidal anti-inflammatory drug phenylbutazone.Hair-based anti-doping testing in horse racing started relatively recently, with analytical methods advancing rapidly over the past decade. But regulators now widely accept the technique, and officials have relied on it as the sole testing method in a number of high-profile regulatory cases, Gray says.In 2017 racing chemists from the Association of Official Racing Chemists (AORC), working in equine anti-doping laboratories certified by the International Federation of Horseracing Authorities (IFHA) collaborated to form a hair analysis committee to both guide and unify horse hair analyses worldwide. The Fdration Equestre Internationale (FEI) has not yet adopted hair analyses for equestrian eventsbut its leaders expressed an openness toward the idea at their 2025 Sports Forum held in Lausanne, Switzerland.Breeding, Screening, and Equine Genomic ResearchThe horses hair root is a great place for harvesting DNA, says Samantha Brooks, PhD, associate professor in equine physiology at UF. Testing that DNA can allow scientists to identify specific types of desired genes, such as the chromosome inversion that leads to tobiano Paint Horse patterns, variants in the SLC24A5 gene that give some Paso Finos tiger eyes, or the base change in DMRT3which contributes to gait patterns such as lateral gaits and for trotting that resists transitioning into a canter.Hair analysis also reveals critical genetic health information. Genetic tests that use 20-30 strands of mane hair with roots can detect genes linked to congenital diseases, including distichiasis (abnormal eyelash growth) in Friesians, cerebellar abiotrophy in Arabians, and hyperkalemic periodic paralysis (HYPP) in Quarter Horses. Such testing gives owners a heads-up about not only diseases their horses might develop but also asymptomatic carriers that when bred with other asymptomatic carriers could produce symptomatic foals.Finally, full genome mapping based on DNA extracted from hair roots allows researchers to trace an individual horses pedigree and breed background, while also helping reconstruct the broader history of domestic horses. By comparing modern horses DNA with ancient DNA from equid fossils across the planet, scientists including Ludovic Orlando, PhD, director at the Centre for Anthropobiology and Genomics of Toulouse, in France, are discovering when and where horses were first domesticated. Theyre even starting to decipher how people domesticated these horses more than 4,000 years agothanks in large part to hundreds of genomes mapped from the manes of our own horses living today. Through such studies Orlando and his team have noticed bottlenecking of certain genes around the time of domestication, such as those coding for good temperament, robust size, and a strong back.Take-Home Message Horses hair contains interesting and often valuable information about their current and future health, the genetic traits they carry, and various drugs or toxins to which they might have been exposed. Ongoing research can help owners, veterinarians, and regulatory authorities take advantage of everything horses hair can tell us.References1. Yang W, Yang Y, Ritchie RO, Meyers MA. On the strength of hair across species. Matter. 2020;2(1):136149.2. stnta S, Paayev N. Physical, thermal, and mechanical of horse tail and mane hairs. Res J Text Appar. 2025;29(2):341355.3. Lima DFPA, da Cruz VAR, Pereira GL, Curi RA, Costa RB, de Camargo GMF. Genomic regions associated with the position and number of hair whorls in horses. Animals (Basel). 2021;11(10):2925.4. Wahl L, Vervuert I. Commercial hair analysis in horses: a tool to assess mineral intake. J Equine Vet Sci. 2022;119:104145.5. van der Merwe D, van den Wollenberg L, van Hees-Valkenborg J, de Haan T, van der Drift S, Vandendriessche V. Evaluation of hair analysis for determination of trace mineral status and exposure to toxic heavy metals in horses in the Netherlands. J Vet Diagn Invest. 2022;34(6):10001005.6. Cygan-Szczegielniak D, Stasiak K. Concentration of selected essential and toxic trace elements in horse hair as an important tool for the monitoring of animal exposure and health. Animals. 2022;12(19):2665.This article is from the Summer 2025 issue ofThe Horse: Your Guide to Equine Health Care. We at The Horse work to provide you with the latest and most reliable news and information on equine health, care, management, and welfare through our magazine and TheHorse.com. Your subscription helps The Horse continue to offer this vital resource to horse owners of all breeds, disciplines, and experience levels. To access current issues included in your subscription, please sign in to theAppleorGoogleapps ORclick herefor the desktop version.

On July 14, a Quarter Horse stallion in Newaygo County, Michigan, tested positive for strangles. The horse developed clinical signs on July 10, including fever and nasal discharge. He is now recovering.EDCC Health Watch is an Equine Network marketing program that utilizes information from the Equine Disease Communication Center (EDCC) to create and disseminate verified equine disease reports. TheEDCCis an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.About StranglesStranglesin horses is an infection caused byStreptococcus equisubspeciesequiand spread through direct contact with other equids or contaminated surfaces. Horses that arent showing clinical signs can harbor and spread the bacteria, and recovered horses remain contagious for at least six weeks, with the potential to cause outbreaks long-term.Infected horses can exhibit a variety of clinical signs:FeverSwollen and/or abscessed lymph nodesNasal dischargeCoughing or wheezingMuscle swellingDifficulty swallowingVeterinarians diagnose horses using polymerase chain reaction (PCR) testing with either a nasal swab, wash, or an abscess sample, and they treat most cases based on clinical signs, implementing antibiotics for severe cases. Overuse of antibiotics can prevent an infected horse from developing immunity. Most horses make a full recovery in three to four weeks.A vaccine is available but not always effective. Biosecurity measures of quarantining new horses at a facility and maintaining high standards of hygiene and disinfecting surfaces can helplower the risk of outbreakorcontain one when it occurs.

On July 18, a suckling Quarter Horse colt in Washington County, Maryland, tested positive for salmonellosis. The foal developed clinical signs on July 14, including fever, diarrhea, and sepsis. He is isolated, and 11 horses are exposed.EDCC Health Watch is an Equine Network marketing program that utilizes information from the Equine Disease Communication Center (EDCC) to create and disseminate verified equine disease reports. TheEDCCis an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.About SalmonellosisSalmonellosis is a contagious and zoonotic bacterial infection caused bySalmonella spp, which causes enterocolitis. Clinically normal horses can transiently shed Salmonella, with shedding more common during:Concurrent illness: antibacterial usage, physiological disturbanceStress: transportation, social, nutritionalGastrointestinal disturbance: motility (especially colic), feed changeClinical signs of salmonellosis include diarrhea, fever, lethargy, anorexia, colic, localized infection, sepsis and septic shock. Foals are commonly more seriously affected with profound systemic illness, including hemorrhagic diarrhea, pneumonia, meningitis, inflammation of growth plate and septic arthritis.Treatment of the severe form of salmonellosis is based on IV fluid and electrolyte replacement and efforts to control the hosts responses initiated by the systemic inflammatory response.Prevention of salmonellosis is difficult, because the organism is present in the environment as well as in the feces of some healthy animals. Isolation and increased biosecurity are needed to prevent spread of the disease.

Eleven horses from multiple parishes around Louisiana have tested positive for Eastern equine encephalitis (EEE), based on testing results from the Louisiana Disease Diagnostic Laboratory. One of the horses has also tested positive for West Nile virus (WNV).EDCC Health Watch is an Equine Network marketing program that utilizes information from the Equine Disease Communication Center (EDCC) to create and disseminate verified equine disease reports. TheEDCCis an independent nonprofit organization that is supported by industry donations in order to provide open access to infectious disease information.EEE 101Eastern equine encephalomyelitis is caused by the Eastern equine encephalitis virus, for which wild birds are a natural reservoir. Mosquitoes that feed on EEE-infected birds can transmit the virus to humans, horses, and other birds. Horses do not develop high enough levels of these viruses in their blood to be contagious to other animals or humans. Because of the high mortality rate in horses and humans, EEE is regarded as one of the most serious mosquito-borne diseases in the United States.Tips for preventing mosquito-borne diseases include:Avoid mosquito bites: Use insect repellent when outdoors, especially from dusk to dawn.Look for EPA-labeled products containing active ingredients such as DEET, picaridin (KBR3023), or oil of lemon eucalyptus (p-menthane 3,8-diol).Apply more repellent, according to label instructions, if mosquitoes start to bite.Mosquito-proof homes: Fix or install window and door screens, and cover or eliminate empty containers with standing water where mosquitoes can lay eggs.Protect your horses: Veterinarians recommend commercially available licensedvaccines against EEE for all horses in the U.S. Horses should be vaccinated at least annually (recommendations vary in high-risk areas). Its not too late this year to vaccinate your horses.Use approved insect repellents to protect horses.If possible, put horses in stables, stalls, or barns during the prime mosquito exposure hours of dusk and dawn.Eliminate standing water, drain water troughs, and empty buckets at least weekly.Stock water tanks with fish that consume mosquito larvae (contact your local mosquito control for assistance), or use mosquito dunks (soliddonuts ofBacillus thuringiensis israelensis, which are nontoxic to horses) available at hardware stores.WNV 101West Nile virusis transmitted to horses via bites from infected mosquitoes. Not all infected horses show clinical signs, but those that do can exhibit:Flulike signs, where the horse seems mildly anorexic and depressed;Fine and coarse muscle and skin fasciculation (involuntary twitching);Hyperesthesia (hypersensitivity to touch and sound);Changes in mentation (mental activity), when horses look like theyre daydreaming or just not with it;Occasional drowsiness;Propulsive walking (driving or pushing forward, often without control); andSpinal signs, including asymmetrical weakness; andAsymmetrical or symmetrical ataxia.West Nile virus has no cure. However, some horses can recover with supportive care. Equine mortality rates can reach 30-40%.Studies have shown thatvaccines can be effective WNV prevention tools. Horses vaccinated in past years need an annual booster shot, but veterinarians might recommend two boosters annuallyone in the spring and another in the fallin areas with prolonged mosquito seasons. In contrast, previously unvaccinated horses require a two-shot vaccination series in a three- to six-week period. It takes several weeks for horses to develop protection against the disease following complete vaccination or booster administration.In addition to vaccinations, owners should work to reduce mosquito population and breeding areas and limit horses mosquito exposure by:Removing stagnant water sources;Dumping, cleaning, and refilling water buckets and troughs regularly;Keeping animals inside during insect feeding times (typically early in the morning and evening); andApplying mosquito repellents approved for equine use.