Causative Agent:
Salmonella is a bacteria that causes diarrhea and systemic infections in foals and adult horses. Some studies indicate that prior oral administration of some antibiotics may create an increased susceptibility in some horses.Clinical Signs: The horse often has a fever, loose (possibly bloody) manure, and becomes dehydrated easily. As the infection persists, the horse may go into shock. Some symptoms of shock are an increased heart and respiratory rate, increased capillary refill time, and inflamed mucous membranes. The horse will often have laminitis as a result of the infection.
Disease Transmission: This bacteria is spread in the manure from one animal to another. This contaminated manure is ingested and the infection begins. It is possible to have a chronic shedder that will spread the organism during times of stress. Buckets, hands, and equipment are often means of transporting infection from one animal to the next. Humans are also very susceptible to Salmonella infections.
Diagnosis: A fecal sample that is tested specifically for Salmonella will identify infected animals. Sometimes the culture must be run 3-5 times, 12-24 hours apart, before a positive result is reached.
Treatment: Most of the time IV fluids are required to maintain proper hydration. If the horse is severely sick, the use of plasma may be necessary. Antibiotics are also required to prevent additional infections. For treating the fever and preventing additional endotoxin release, NSAIDS are recommended (Banamine). For treating and preventing laminitis, NSAIDS (bute), Ace, and frog supports are beneficial. See page E465 for laminitis treatment. Because of potential side effects, do not administer two NSAIDS at the same time.
Prevention: When an animal is sick with diarrhea, special care is required to prevent disease transmission from one animal to another. Clean gloves, clean coveralls, and proper sterilization of equipment are essential to help prevent disease transmission. It is often necessary to designate one pair of coveralls and equipment for that specific horse. Before these materials are used again on another animal, they must be completely sterilized. The sick animal should also be isolated.