The paper is focused on the analysis of the occurrence of cryptosporidiosis in calves during the milk feeding period. Long-term monitoring of the health status of 1047 calves over five years in one herd resulted in the proposal of preventive measures aimed at limiting the occurrence of the pathogen, increasing the level of passive (colostral) immunity of calves, including compliance with the hygiene of the breeding environment and sanitation of housing, feeding, and drinking buckets.