Also called dryland distemper or Colorado strangles, pigeon fever develops when Corynebacterium pseudotuberculosis bacteria enter a horse’s body, probably via insect bites or breaks in the skin. It has nothing to do with birds except the shape of the external infections often resemble the breast of a pigeon.
The infection appears in three forms:
- External abscesses develop just under the skin or within the muscles near the surface of the body
- Internal abscesses develop when the bacteria are carried into the body and infect the liver, kidney, lungs or other internal organs
- Ulcerative lymphangitis, which causes swelling and ulcerations on the lower legs
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