Pigeon Fever, also called dryland distemper or false strangles, is not the most serious disease that can affect a horse. It is a bacterial infection that creates purulent abscesses. Corynebacterium pseudotuberculosis thrives in soil contaminated with manure, especially in hot, droughty conditions. When horses roll or lie down in paddocks or churn up clouds of bacteria-laden dust, the organisms may enter wounds, insect bites or breaks in the skin. House flies, stable flies and horn flies have all been found to be carriers and may transmit the infection from horse to horse. Composting manure or removing it from your property also helps keep fly populations down.
- Isolate infected horses. The pus that drains from a pigeon fever abscess is loaded with bacteria that can easily persist in that soil and infect other horses.
- Quarantine new horses. Horses may carry pigeon fever for three to four weeks before showing signs and the shipment of carriers around the country may be contributing to the spread of the infection beyond its former boundaries. When bringing new horses onto your property, keep them isolated from resident horses long enough to be sure they are not incubating any infections. House newcomers in a separate barn or pen as far as possible from other horses for at least three weeks.
The disease takes three forms:
- External abscesses form under the skin or in the musculature.
- Internal abscesses form within the internal organs, usually the lungs, liver, spleen or kidneys.
- Ulcerative lymphangitis affects the lower legs.