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/714009
34 TheHorse.com THE HORSE September 2016 I t's 6 a.m. A chorus of nickers greets you as you walk into the barn. You partition out scoops of feed and pour them into buckets. Eager muzzles gobble up breakfast. At 6 p.m., a different scene. No nickers for dinner. Lethargic, sweaty horses stand stoically in their stalls. You call the vet- erinarian immediately, and he mentions possible feed contamination. You have no idea how that could have happened. Your horses have been fed the same feed for years. Could this really be the cause? Feed safety remains front of mind for owners, given the multitude of news stories about horse feed contamination in recent years. Because most contami- nants are undetectable to the naked eye, knowing the risks and asking the right questions can be key to keeping dinner from becoming deadly. Types of Grain Contamination Feed can be corrupted at any point during its progression from field to feed bucket—that includes growing, harvest- ing, feed mill processing, transportation, storage, and dispersal. Risks range in severity from simply affecting a grain's nutrient value to causing life-threatening health issues in the horses that consume it. Let's take a look at the two major types of contaminants: natural and medicinal. Natural Contamination: Microorganisms Bacteria, fungi, and molds are the types of microorganisms potentially found in feeds. They typically infiltrate feed ingredients when they are plants (in the soil, by insects on crops, or by fertilization of crops with manure) or during storage. Feed type, processing methods, and stor- age conditions all influence the amount and types of microorganisms present. The bacterial species that most com- monly contaminate feeds and cause equine health concerns are Clostridium, Escherichia coli, and Salmonella. These bacteria contaminate feed when produc- ers use manure to fertilize grain crops in the field or when bird and rodent feces come in contact with the feed at the mill or on the farm. In two surveys conducted in 1993 and 1997, the Food and Drug Administration (FDA) found Salmonella contamination in feed mills likely from bird excrement. Horses can transmit these bacteria, once ingested, to humans and other animals, making disease risk a serious concern. Toxins produced by C. botulinum can thrive with improper hay curing or drying and cause botulism. Grains can be host to molds and fungi while growing in the field as well as during storage in the mill. The mold As- pergillus parasiticus, for example, infects corn kernels in the field during stressful environmental conditions (e.g., drought) and produces toxins called aflatoxins. In stored feed, with the right combination of moisture and temperature, molds can produce toxins known as mycotoxins. Corn is most susceptible to mycotoxin contamination. Molds and fungi can not only decrease grain quality but also cause a slew of health problems for horses, ranging from mild allergies to equine leukoencephalomalacia (moldy corn poisoning due to ingesting the mycotoxin fumonisin). Medicinal Contamination: Antibiotics & Other Drugs Just like physicians, veteri- narians rely on antibiotics for treating and preventing disease in their patients. In certain livestock species, such as cattle and poultry, farmers use low doses of specific antibiotics to improve growth rates, feed utilization, and reproductive NUTRITION KRISTEN JANICKI, MS, PAS TheHorse.com/Nutrition How Dinner Turns Deadly Ways your horse's feed can become contaminated and what regulations are in place to help prevent it Your horse's feed can become contaminated during growing and harvesting, processing, or during transportation, storage, or dispersal. FRANK SORGE/ARND.NL