1. In veterinary medicine, an uncommon but serious chronic pyogranulomatous infection of horses, cattle, cats and dogs caused by Pythium insidiosum an oomycete fungus-like agent. Abbreviated taxonomy:Eukaryota; Stramenopiles; Oomycetes; Pythiales; Pythiaceae; Pythium, common in the Gulf Coast states of the U.S., but also found in many subtropical and tropical regions around the world. Seen in moist soil environments and water where motile chemotactic zoospores enter skin or mucosa of the host; agent causes gastric, pancreatic, and intestinal granulomas or bowel obstruction in dogs, usually leading to gastrointestinal signs such as diarrhea and vomiting; elicits subcutaneous pythiosis in horses; rare ophthalmic or disseminated cases occur; can also affect humans.
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