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blackhead

bird disease
Also known as: enterohepatitis, histomoniasis

blackhead, acute liver and intestinal disease of turkeys, chickens, and other game birds, caused by the protozoan parasite Histomonas meleagridis that lives in eggs of the nematode Heterakis gallinarum. Chief symptoms are listlessness and sulfur-coloured diarrhea. Blackhead is usually fatal in turkeys.

This article was most recently revised and updated by Erik Gregersen.