Bovine cryptosporidiosis.

Intestinal cryptosporidiosis was detected at necropsy in a 2-week-old calf that had diarrhoea. Cryptosporidial organisms were embedded in the microvillous border of the epithelium of the distal small intestine. The most significant histological change was a mild enteritis characterized by decreased villus length and hypercellularity of the lamina propria.