Effect of supranutritional maternal and colostral selenium supplementation on passive absorption of immunoglobulin G in selenium-replete dairy calves

Abstract Selenium (Se) is an essential micronutrient for ruminant animals affecting both performance and immune functions. Adding 3mg of Se/L (in the form of Na selenite) to colostrum has been shown to improve IgG absorption in Se-deficient newborn dairy calves. The objective of our study was to determine the effect of supranutritional maternal and colostral Se supplementation on IgG status of Se-replete dairy calves. The study design was a 2×2 × 2 factorial design. During the last 8 wk before calving, dairy cows at a commercial dairy were fed either 0 (control cows) or 105mg of Se-yeast once weekly (supranutritional Se-yeast-supplemented cows), in addition to Na selenite at 0.3mg of Se/kg of DM in their ration. After birth, calves were fed pooled colostrum from control or supranutritional Se-yeast-supplemented cows to which 0 or 3mg of Se/L (in the form of Na selenite) was added. Concentrations of whole-blood (WB) Se and serum Se measured at birth and at 48h and 14d of age, and serum IgG concentrations measured at 48h and 14 and 60d of age were determined. Calves born to Se-yeast-supplemented cows had higher WB-Se and serum-Se concentrations for the first 2 wk, and higher IgG absorption efficiency (62% at 48h), resulting in higher serum-IgG concentrations (43% at 48h and 65% at 14d) and higher total serum-IgG content (50% at 48h and 75% at 14d), compared with calves born to control cows. Calves that received colostrum with added Na selenite had higher WB-Se concentrations for the first 2wk, but only at 14d of age were serum-Se concentrations, serum-IgG concentrations (53% higher), and total serum-IgG content (56% higher) higher, compared with calves that were fed colostrum without added Na selenite. Calves born to Se-yeast-supplemented cows that received colostrum from Se-yeast cows without added Na selenite had a higher IgG absorption efficiency compared with all other treatment groups. Our results support that feeding cows supranutritional Se-yeast supplement during the dry period or spiking colostrum with Na selenite both improve IgG status of Se-replete calves.