The transition period — three weeks before to three weeks after calving — is the highest welfare-risk phase for dairy cows, with most metabolic disease and welfare problems concentrated in this critical period.
Transition cows face a physiological crisis as they shift from pregnancy to lactation, placing enormous metabolic demands on their bodies. Diseases including ketosis, milk fever, and mastitis cause significant pain and distress. Many go undetected in large herds until severely ill. Housing conditions during transition directly influence disease rates — overcrowding, feed competition, and inadequate lying space all increase metabolic disease. The transition period represents the single highest-leverage welfare improvement opportunity in dairy production.