The present study is focused on determination the principles of biosecurity for the calf rearing during the milk feeding period. The most common transmission of pathogens during calf rearing occurs by means of animals, people, technological systems, feed, water and bedding, contaminated equipment, vehicles, wild animals or air. Strict adherence to the principles of biosecurity and maintaining a high hygienic standard of rearing is an important prerequisite for maintaining good health and welfare of calves.