Cryptosporidiosis in Tanzanian goat kids: scanning and transmission electron microscopic observations.

Trophozoites, gametes, and schizonts characteristic of Cryptosporidia were demonstrated in 2 Tanzanian goat kids. In a heavily infected kid the parasite was associated with villous atrophy and crypt hyperplasia. An enhanced epithelial cell ageing and extrusion rate, possibly due to a drain on cell metabolites by the parasite, is suggested. The protozoan seemed to induce host cell specializations, including parasitophorous envelope and development of smooth-membraned vesicles. The vesicles possibly have a function in the transport of nutrients from the host cell to the parasite.