Risk Reduction

INFECTIOUS DISEASES ARE A CONSTANT RISK to the health and welfare of horses. The threat of strangles, influenza, equine herpesvirus, rotavirus, Salmonella, Rhodococcus, etc. are only some of the reasons for a comprehensive vaccination program. However, no vaccine is 100% effective, and vaccines are not commercially available for many diseases, including the dreaded salmonellosis.

However, multiple farm management techniques can have a significant influence on reducing the risk of disease outbreaks. Not all are as labor intensive as completely disinfecting stalls and aisleways. These techniques include:

Group horses of similar uses. Show horses, yearlings, broodmares, riding horses, should not be commingled.
Plan a traffic pattern to take farriers, veterinarians, and other personnel to barns and pastures with at-risk horses (e.g., pregnant mares or mares and foals) first, and work toward horses that have multiple exposures to pathogens (show and trail riding horses).
Isolate any new horses to the farm for a minimum of 14 days, and ideally 21 days. The horse can be monitored for infectious diseases, and any necessary vaccinations and deworming can be completed at that time.
Isolate horses returning from a hospital stay for similar periods of time. The stress of transportation and medical procedures can lower horses’ immunity, and they may come in contact with other equine patients, some of which may be shedding pathogens.
If a horse is observed as being sick (cough, runny nose/eyes, diarrhea, fever, etc.), it should be isolated immediately and protective clothing utilized by everyone working with the animal: disposable gloves and booties and coveralls should be re-used only with that horse. Be sure to provide alternative gloves for employees who are allergic to latex, such as gloves made of nitrile or vinyl.
Stalls of sick horses should be mucked out last, and preferably separately, using pitchforks, shovels, and other tools that are properly disinfected prior to their next use. Alternatively, use separate tools for healthy horses’ stalls and a different set for sick animals’ stalls.
Manure and bedding from stalls housing sick animals, including those experiencing abortions, should not be spread on fields. This material should be composted away from all animals or disposed of in a manner approved by local ordinances.
In every barn provide running water, liquid hand soap (pump-style container), and disposable paper towels for handwashing. All employees should wash their hands prior to leaving at the end of their shift, and in the midst of a disease problem, they should thoroughly wash their hands after working with sick animals, whether or not they were wearing disposable gloves. During an outbreak or when running water is not available, have waterless hand foams or gels (at least 62% ethyl alcohol) to use after handling horses. Remind employees that these products are flammable!
Rodent control is paramount year-round! One barn mouse can ingest Salmonella and be a multiplication factory better than any petri dish. The mouse droppings contain enormous amounts of bacteria that can effectively seed the horse’s environment and feed supply with infectious bacteria. Insect, bird, and bat control are also important. Remove standing water, bird nests, and other habitats. Hire professionals for removal of bat roosts and also for difficult rodent or wildlife control.
Clean and disinfect stalls, water buckets, grooming tools, pitchforks, and other items routinely, and increase the frequency during an outbreak situation.
Most importantly, communicate and educate employees and enforce biosecurity procedures on the farm.

Dr. Roberta Dwyer, (859) 257-4757, rmdwyer@uky.edu,
Maxwell H. Gluck Equine Research Center, University of Kentucky, Lexington, Kentucky.