[The economic significance of coccidia of the genus Cryptosporidium in calf rearing].

In five large calf-houses and seven farms, 943 calves at the age from one to 198 days were examined coprologically; the feces of 224 animals (23.7%) contained coccidium oocysts of the genus Cryptosporidium. The cryptosporidium oocysts were counted in the Bürker chamber by means of the original method, and their mean number in 1 g of feces was the highest in the animals of the age from 11 to 20 days (3.0 +/- 2.4 million in the calves suffering from scours and 4.2 +/- 4.1 million in the calves without scours). Statistical comparison of the mean weights of heifers was performed at the time of their delivery to the calf-house and showed no statistically significant influence of cryptosporidia on the weight of animals.