Horses and rats don’t mix. For their size, rats can cause an inordinate amount of destruction in barns by such acts as chewing electrical wiring, eating through feed bags and ruining surfaces with their waste. Not known to be primary transmitters of disease to horses, rats nonetheless can transmit disease via urine, parasites and the occasional carcass getting into the horse's feed. For the overall health of your horses and their human handlers, take steps to rid your barn of rats.
Rat feces are but one source of the salmonella bacteria that can cause salmonellosis in horses; the bacteria also spreads via birds and other farm animals. This bacteria is stubborn and can live in water, soil and feed for months. It can survive in dried feces for more than two years, so remove any rat feces you find. The most common symptoms are diarrhea and mild to severe colic or digestive upset with or without diarrhea. Contact your veterinarian if your horse gets diarrhea, as persistent diarrhea can be fatal. A fecal culture is the only sure way to diagnose salmonellosis.
Leptospirosis is caused by a bacteria found in animal urine, including that of rats. Any direct contact with the bacteria can cause this disease, including drinking infected water or eating infected hay. Bacteria may enter through an open wound or through the eyes, nose or mouth. Leptospirosis is believed to be one cause of “moon blindness” in horses. If you notice cloudiness in your horses’ eyes or a sudden sensitivity to light, contact your veterinarian immediately.
Your horse could get a disease called trichinosis if he eats anything that had infected and rotting rat carcasses in it, so it's important to keep rats out of feed bins and hay storage areas. Trichinosis is caused by ingesting the larvae form of the trichinella roundworm. It more commonly is caused by eating the raw meat of infected animals.
Other Rat Problems
Though rat feces are not known to directly cause many diseases in horses, their presence in barns and stables with horses can harbor health issues. Rats carry ticks, lice and fleas. Chewing electrical wires creates a fire hazard. Female rats can give birth to more than 50 babies per year -- with those female babies quickly able to multiply -- so work quickly to stop an infestation.
- Ontario Ministry of Agriculture, Food and Rural Affairs: Rodent Control in Horse Stables
- Purdue Indiana Animal Disease Diagnostic Laboratory: Enteric Salmonellosis in Horses
- Iowa State University Center for Food Security and Public Health: Leptospirosis
- Mayo Clinic: Trichinosis
- America’s Horse Daily: Causes of Moon Blindness
- horse grazing image by Wendi Evans from Fotolia.com