Effects of 25-hydroxyvitamin D3 on growth performance, fecal scores, vitamin D3 metabolites, antioxidant status, and inflammatory and stress-related parameters in weaning calves

The objectives of this study were to evaluate the effects of milk replacers containing 25-hydroxyvitamin D3 [25(OH)D3] and enriched with vitamin D3 on the growth performance, fecal scores, vitamin D3 metabolites, biochemical blood parameters and antioxidant, inflammatory and stress-related parameters of Holstein male calves. Thirty Holstein male calves (body weight = 41.4 ± 2.79 kg) were randomly assigned to three groups for a 56-day experimental period. The control group received milk replacer containing 1.2 mg/kg vitamin D3, the VD group received milk replacer containing 13.2 mg/kg vitamin D3, and the 25D group received milk replacer containing 300 mg/kg 25(OH)D3 plus 1.2 mg/kg vitamin D3 until weaning at day 54. On days 52, 57 and 59, which were defined as days -2, 3 and 5 postweaning, blood samples were collected to measure biochemical blood parameters and antioxidant, inflammatory and stress-related indicators. Calves that received milk replacer containing 25(OH)D3 consumed more calf starter at one week postweaning (P 2 overall periods. Calves fed 25(OH)D3 had increased serum 25(OH)D3 during the preweaning (P