The Horse:Your Guide To Equine Health Care provides monthly equine health care information to horse owners, breeders, veterinarians, barn/farm managers, trainer/riding instructors, and others involved in the hands-on care of the horse.
Issue link: https://thehorse.epubxp.com/i/821826
5 June 2017 THE HORSE TheHorse.com Compared to other, smaller mammals, horses are much more sensitive to botulism. TheHorse. com/29975. Sponsored by Neogen. While hoof abscesses can be extremely painful, they usually resolve easily with treatment. TheHorse. com/39121. Sponsored by Kentucky Performance Products. David Horohov, PhD, University of Kentucky Gluck Equine Research Center director, gives an overview on vaccines and immune response. TheHorse.com/ UKLecture. Sponsored by Zoetis. WHAT'S ONLINE ■ THE HORSE HEALTH This award-winning e-newsletter offers news on diseases, veterinary research, and health events, along with in-depth articles on common equine health condi- tions. Supported by Zoetis . ■ HORSE WELFARE AND INDUSTRY Get the latest news on equine welfare, industry happenings, and horse-related business news. ■ SPECIALTY WEEKLY E-NEWSLETTERS Nutrition Lameness Reader Favorites MONTHLY E-NEWSLETTERS Behavior Breeding Equinomics Older Horse Care Sports Medicine Bluegrass Equine Digest is published monthly in partnership with UK Ag Equine and the Gluck Equine Research Center and is supported by Zoetis . E - NEWSLETTERS Get Horse Health News Delivered To You! All About Nutrition At A Glance: Equine Supplements CURRENTLY on Send your questions to THEditorialStaff@ TheHorse.com. Sponsored by LMF Feed. ■ More Work Might Mean Your Horse Needs More Calories TheHorse.com/39109 ■ How Long Can I Store Feed? TheHorse.com/39050 ■ Feeding Type-1 PSSM Horses TheHorse.com/39081 Market study results show more than half of all U.S. horse owners offer their horses some type of supplement. Find out which ones might be right for your horse. TheHorse. com/39100. Sponsored by ADM Animal Nutrition. Watch: Equine Vaccinations: What, When, and Why Fact Sheet: Botulism in Horses At A Glance: Hoof Abscesses What's New in Equine Parasite Control? Do you know the right way to deworm your horse? Join us as Martin Nielsen, DVM, PhD, Dipl. EVPC, ACVM, answers your questions about parasite control. Visit TheHorse.com/ AskTheHorseLive . Thursday, June 8, at 8 p.m. EDT 1 F all is the ideal time to overseed cool-season pastures to thicken a stand and fi ll in bare areas. The following recommendations will improve the chances of a successful overseeding. Apply any needed lime and fertilizer amendments. An up-to-date soil test will indicate which nutrients are needed for both established and growing plants. For more informa- tion, contact your local county Extension agent or consult the University of Kentucky (UK) publication Soil Sampling and Nutrient Management in Horse Pastures at uky.edu/Ag/ Forage/agr200.pdf . Additionally, applying nitrogen in the fall can benefi t new seedings as well as most horse pastures. Spread two applica- tions of 30 to 40 pounds per acre of actual nitrogen 45 days apart to thicken stands and increase winter survival rates. Use high-quality seed of an improved variety . Use a seed variety that has proven to be a top performer under conditions in your area. The UK Forage Variety Testing Program looks at the seed- ling vigor, stand persistence, yield, and survival under horse grazing. Find this data in the Forage Variety Trials reports at uky.edu/Ag/Forage/ foragevarietytrials2.htm . High-quality seed has good germination rates and is free of contamination from weed seed. Remember, quality seed will produce a pasture that lasts for years; "cheap seed" will only lead to headaches. Purchase seed well in advance, as quality seed will be in high demand close to planting dates. Store seed in rodent-proof containers in a cool, dry area. If you plan to store seed for more than six months, keep it in a refrigerator to maintain viability. Plant enough seed at the right time. Seeding rates are determined by the grass mixture you choose to plant. See Table 1 (above right) for the recommended seeding rates for common forage plants. Also, be sure to seed as early as possible—anywhere from mid-August to mid-September is ideal for Kentucky and most northern states, while later in the year is better in the Deep South). Use the best seeding method available. No-till drill seeding is recommended for overseeding existing pastures. But with any method, place the seed ¼ to ½ of an inch into the soil and cover it to achieve good seed-to-soil contact. Drill seed in two directions across the fi eld to ensure better coverage. Control competition. Close mowing or grazing prior to overseeding in the late summer and fall will reduce weed and grass competition. Be sure to follow recommended waiting periods when applying herbicides. In addition to limiting grazing of an overseeded pasture, limit herbicide applications at critical times. It's typically recommended to seed at least six weeks after spraying and wait until the grass seedlings are at least 4 to 5 inches tall before spraying again. Always follow herbicide labels—some of the newer herbi- cides have even longer waiting periods. For more informa- tion, see Weed Management in Grass Pastures, Hayfi elds, and Other Farmstead Sites at c a.uky.edu/agc/pubs/agr/agr172/ agr172.pdf . Allow time for seedlings to establish. Returning horses to an overseeded pasture too soon can wipe out any seed- lings via grazing or trampling. Ideally, a pasture should have six months of rest after overseeding before heavy grazing resumes; however, seedlings can generally tolerate a few light grazing sessions. Harvesting the pasture once for hay after the grass has reached maturity and before returning B luegrass Equine DIGEST CA.UKY.EDU/EQUINE ❙ THEHORSE.COM ❙ JULY 2016 Tips for Overseeding Fall Horse Pastures In is Issue Estate Planning Tips for Horse Owners 02 The Grass Guide: Large Crabgrass 05 I'm Selling My Horse. What Should I Disclose? 06 UK Researcher Develops New Tall Fescue Variety 07 UKVDL Releases New Testing Fees 12 TABLE 1 COMMON SEEDING RATES AND OPTIMUM SEEDING DATES FOR HORSE PASTURES Species Rate lb/A (seeded alone) Rate lb/A (in mixtures) Optimum Seeding Dates* Novel or endophyte- free tall fescue 20 - 40 10 - 20 8/15 - 9/15 Orchardgrass 15 - 30 10 - 15 8/15 - 9/15 Kentucky bluegrass 15 - 30 10 - 15 8/15 - 9/15 Endophyte-free perennial ryegrass 20 - 40 5 - 10 8/15 - 9/15 *Seeding dates are for Kentucky and the transition zone. Using high-quality seed is essential for a successful overseeding. UNIVE RSITY OF KENTUCKY ALEXANDRA BECKSTETT ANNE M. EBERHARDT/THE HORSE Rapidly changing wet- dry climates or wet-frozen environments. ese conditions can degrade hoof quality and lead to bruising and injuries. Poor hoof quality or conformation. Weak and/or imbalanced hooves are more vulnerable to the injuries that predispose a horse to abscesses. Neglected hoof care. Lack of hoof hygiene and proper trimming and farriery can lead to weakened hooves. Pituitary pars intermedia dysfunction (PPID or equine Cushing's disease) or other immune-system compromising diseases. Diseases that affect the immune system make horses more prone to infection. Rocky or hard footing. Poor footing can result in bruising, which can turn into an abscess. Oen, hoof abscesses will "blow" or pop open and ooze a smelly pus, usually giving the horse near-immediate relief from the painful pressure. There are two common types of hoof abscesses: SubSolaR — Under the sole, which typically vent at the white line, bars, or heel bulbs. SubmuRal — Under the wall, which typically vent at the coronary band. Hoof abscesses oen result from an initial trauma, such as bruising or a puncture, which allows bacteria into the foot, where infection festers. Management practices and health condition s can make horses more susceptible to getting hoof abscesses. A At Glance S P O N S O R E D B Y Clinical signs of a hoof abscess include: ♦ Lameness, oen severe and nonweight-bearing; ♦ Swelling in the associated leg; ♦ Localized heat; ♦ Drainage or evidence of a "tract"; and ♦ Increased digital pulse in the affected limb. Cushing's disease Poor hoof care Subsolar Frozen ground Submural A hoof abscess is a localized infection of a horse's foot, usually behind the hoof wall or sole. While hoof abscesses can be extremely painful, they usually resolve easily with treatment within days. 3-5 MAUREEN FLIETNER ISABELLE ARNON Hoof Abscesses By Michelle Anderson, The Horse Digital Managing Editor Reviewed by Vernon Dryden, DVM, CJF, Bur Oak Veterinary and Podiatry Services Photos by iStock Hoof abscesses require wrapping to keep the area clean and prevent further infection. Th E hORSE STAFF BOTULISM FAC T SHEET SponSored By Botulism in Horses Horses are highly susceptible to botulism, which causes neurologic disease and death Authored by StAcey o ke, dVM, MSc; reViewed by AMy John Son, dVM, d ipl. AcViM C lostridium botulinum neurotoxin (BoNT), the underlying cause of botulism, tops the world's list of potent toxins, which means BoNT is more poisonous than snake and spider toxins, arse- nic, and mercury. 1 Compared to other, smaller mam- mals, horses are much more sensitive to BoNT. For example, it takes less BoNT to kill a horse than it does to kill a mouse. WHAt is Botulism? Botulism in horses results following ingestion or exposure to BoNT produced by the bacterium C. botulinum . This ubiquitous, soil- dwelling, spore-forming bacterium produces several distinct forms of the highly potent BoNT (labeled A through H), as well as several sub- types. 2 Of those, type B most commonly affects horses and foals. Types A and C also occur in the United States, but far less frequently. 3,4 Once absorbed by its victim, BoNT blocks the transmission of impulses, or signals, between nerves and muscles. Due to this "radio silence," muscles throughout the body become progressively weak, es - pecially those in the head and neck. Paralysis promptly ensues, which all too frequently results in the rapid demise of affected individuals. 3,4 exposure in Horses Regardless of the exact "type" of toxin, horses and foals typically become victims of BoNT through one of the following routes: 5,6 1. Forage poisoning Horses (and sometimes foals) ingest BoNT directly, usually when offered hay or haylage contaminated with C. botulinum . Forages become contaminated with the soil-dwelling bacterium either dur- ing raking and baling or due to improper storage. Deceased animals trapped in forage during feed processing or where baleage or hay bales are stored allows BoNT to enter feed (e.g., through packaging punctures). Unfortunately, offending feeds don't necessarily look or iSto C k.C om Free-feeding horses from large hay bales can increase botulism risk, because owners aren't handling the hay daily and therefore are less likely to identify bales contaminated. with dead animals. smell spoiled, making it almost impossible to pre-emptively screen for spoiled sustenance. In herd situations, outbreaks can occur, with several adult horses falling ill simultaneously. 2. ingesting C. botulinum spores Foals, being naturally inquisitive, ingest bacterial spores from the soil while exploring their environment and grazing. The spores then produce BoNT, which is absorbed from the gastrointestinal tract into the bloodstream and subsequently spread throughout the foal's body. This form of botulism is usually referred to as toxicoinfectious botulism or "shaker foal syndrome," so named because of the violent muscle tremors affected foals exhibit. 3. Wound contamination C. botulinum spores can invade wounds, such as castration sites, umbilical hernia repairs, and deep punctures. The spores then produce toxins within the wounds that, once absorbed systemically, cause clini- cal signs of disease. CliniCAl signs In adult horses, the head and neck muscles typically become affected first. Characteristic signs of botulism prior to recumbency (down and unable to rise) include reduced tongue strength and slow or absent tongue retraction. Other classic signs of botulism include: ◆ Drooling, dropping food, dysphagia (inability to swallow), and inap - petence/anorexia; ◆ Pacing; ◆ Weakness, exercise intolerance; ◆ Muscle tremors; ◆ Depression; and ◆ Lying down more frequently or for longer periods of time and, ultimately, recumbency. Although the botulism disease process is the same as in adult horses, foals with botulism remain bright and responsive and show slightly different signs of disease, such as: ◆ An increased amount of time lying down; ◆ Rapidly developing muscle tremors when encouraged to stand and a tendency to flop easily to the ground in lateral recumbency; ◆ Drooling; ◆ Weak eyelid tone; ◆ A tongue that is easily pulled from the mouth and retracts slowly; and ◆ Constipation and ileus (lack of intestinal contractions). DiAgnosis Veterinarians can find botulism challenging to diagnose, especially when only one horse in a herd is affected. Diagnosing botulism using laboratory tests can be time-consuming, expensive, and worst of all, incorrect. 4 Due to the continued lack of a sensitive "gold standard" test for botulism, diagnosing botulism remains clinical, meaning the veterinar- ian has made every attempt to rule out all other possible causes of dis- ease, leaving botulism highly suspected. 4 Differential diseases include rabies, the viral encephalitides (e.g., Eastern, Western, and Venezuelan equine encephalitis), equine protozoal myeloencephalitis, the neuro- logic form of equine herpesvirus-1, West Nile virus, wobbler syndrome A At Glance S P O N S O R E D B Y Market study results show more than half of all horse owners in the United States offer their horses some type of supplement. ose supplements typically fall into two categories: 1 Nutritional or feed supplements, which are designed to meet a horse's needs when certain nutrients—such as vitamins or minerals— are missing from the diet. Example : A hay analysis might reveal that your horse's forage is deficient in certain vitamins and minerals necessary for ba sic bodily functions and optimum health. A carefully selected supplement can help fill the void . 2 Health supplements, which are intended to support maintenance of normal biological structure and function. Example: Your aging sport horse is showing early signs of osteoarthritis- a ssoc iated discomfort, so your vete rinarian recommends a joint- support suppleme nt containing ingredie nt s backed by research showing improved joint function in study horses . By Michelle Anderson, The Horse digital managing editor Reviewed by Clair Thunes, PhD, Summit Equine Nutrition Photos by iStock Equine Supplements Supplements ingredients can include: ♦ Vitamins; ♦ Minerals; ♦ Herbs; and ♦ Other botanicals. On the market you'll find many different supplements purported to offer a myriad of benefits for horses. Health supplements include claims to support: ♦ Joints; ♦ Pain management; ♦ Gastrointestinal tract/ digestion (e.g., gastric ulcers, and sand colic); ♦ Anxiety/stress (i.e., calming supplements); ♦ Hoof health ; ♦ Shiny, healthy hair coats; ♦ Respiratory health; ♦ Allergies; ♦ Metabolic issues; ♦ Energy; ♦ Anhidrosis; ♦ Insect control; ♦ And more. An analysis measures hay's nutrients. Joint supplements are a popular choice for horse owners. Pam mcKenzie Pam mcKenzie Hoof health Shiny coats Anxiety/stress Metabolic issues Allergies