Female calves, checked for serum total protein ≥ 5.8 g/dL before 5 days of life, entered the study at 22 days of age after having received pasteurized colostrum and milk (P group, n = 127), or non-pasteurized colostrum and milk (NP group, n = 134). During the heifer-rearing period, productive (body weight; BW) and health parameters (bovine respiratory disease (BRD) and diarrhea) were recorded. Productive (305-d milk yield), reproductive (AI per pregnancy and calving interval), and health parameters (milk somatic cell count; SCC/mL), as well as age at culling, were recorded in a follow-up study. Feeding on-farm pasteurized colostrum and milk during the first 21 days of life reduced morbidity of bovine respiratory disease during the first year of life and diarrhea during the first 180 days of life. Moreover, it increased BW at calving during the first three lactations. It also significantly increases milk production during the first lactation. However, there were no differences in relation to reproductive performance and health of cows in the NP or P group. These results highlight that feeding calves with pasteurized colostrum and milk could improve health and production parameters throughout the heifer-rearing process and during their first lactation.
Keywords: colostrum; dairy; long-term effects; milk; pasteurize.