Cryptosporidium andersoni
(Lindsay et al., 2000, J. Eukaryot. Microbiol. 47: 91-95)

Nomarski interference contrast photomicrograph of oocysts from calf feces. Each oocyst measures about 7.4 x 5.5 micrometers.	Histological section through stomach (gastric glands) of steer showing developmental stages