Effects of three methods of oral selenium-enriched yeast supplementation on blood components and growth in Holstein dairy calves

The objective of this study was to investigate the effect of three methods of oral selenium-enriched yeast (Se-yeast) supplementation on the blood characteristics and growth of Holstein dairy calves. The three methods were: (1) maternal (dams supplemented with 0.3 mg Se per kg of dietary DM during 3 weeks pre-calving), (2) post-calving (calf starter enriched with 0.3 mg Se per kg of DM), and (3) maternal and post-calving Se-yeast supplementation. These three methods were compared with a control group (no supplementation). Maternal supplementation with Se-yeast successfully increased Se concentration in the colostrum and the serum of calves 24 h after calving (P < 0.05). At day 56, the Se concentration in the blood of calves supplemented with Se-yeast pre- (maternal) or post-calving (via starter) was greater than the control group (P < 0.05), but maternal plus post-calving supplementation was not more effective than either maternal or post-calving supplementation. Globulin and total protein concentration in the blood of calves at day 0 increased and albumins:globulins decreased with maternal supplementation (P < 0.05), but these variables were similar for all treatments at day 56. Immunoglobulins in the blood of calves and colostrum were not affected by maternal Se-yeast supplementation. Maternal supplementation increased the concentration of urea in the blood of calves at 0 days (P < 0.05), but not at 56 days. Calf birthweight was increased with maternal supplementation of Se-yeast (P < 0.01), but growth to day 56 was not affected by the methods of Se supplementation. Maternal supplementation with Se-yeast may improve growth and health characteristics of calves at calving time.