Rhizopus microsporus segmental enteritis in a cow.

A ten year-old Holstein cow had an intermittent bloody diarrhea, evolving to anorexia and recumbency, followed by death. Mycotic segmental enteritis was diagnosed based on the pathological and immunohistochemical findings. Rhizopus microsporus was identified as the causal agent through fungal culture and PCR analysis. Intestinal mucormycosis is poorly described in cattle and should, therefore, be included as a differential diagnosis in cases of diarrhea and death in ruminants, especially when there is disruption of the normal balance of the alimentary microbiota.