Passive immunoglobin transfer in newborn calves fed colostrum or spray-dried serum protein alone or as a supplement to colostrum of varying quality

Two experiments were conducted to investigate the effect of serum-derived i mmunoglobin (Ig) source and the effect of colostrum supplementation with se rum-derived Ig on the attainment of passive immunity in newborn colostrum-d eprived calves. In experiment 1, colostrum-deprived Holstein bull calves we re fed pooled colostrum (PC, n = 9), spray-dried bovine serum (BS, n = 11), or spray- dried porcine serum (PS, n = 9). All treatments were balanced to provide 45 g of IgG in a 2-L volume at birth and again 12 h later. Calves receiving BS had higher 24-h serum IgG concentrations than did calves recei ving PC or PS (8.3, 5.7, and 4.2 g of IgG/L for BS, PC, and PS, respectivel y). In experiment 2, the effect of supplementing bovine colostrum of varyin g quality with BS on Ig absorption was assessed. Thirty-two colostrum-depri ved Holstein bull calves and four freemartin heifer calves were allotted by birth order to receive one of three treatments. Treatments consisted of 1) 2 L of pooled high quality colostrum (95.8 g of IgG, 0% from BS), 2) 2 L o f pooled medium quality colostrum mixed with BS (95.2 g of IgG, 47% from BS ), or 3) 2 L of low quality colostrum mixed with BS (98.8 g of IgG, 70% fro m BS). Serum IgG concentrations at 24 h after treatment were greater for ca lves receiving medium and low quality colostrum supplemented with BS (6.2, 9.6, and 9.6 g of IgG/L for high, medium, and low quality colostrum, respec tively). Similarly, apparent efficiency of IgG absorption was greater for c alves receiving medium and low quality colostrum supplemented with BS (25, 37, and 38% for high, medium, and low quality colostrum, respectively). The results of these studies suggest that dried BS contains a concentrated sou rce of Ig, which is efficiently absorbed by newborn calves. Supplementation of marginal or low quality colostrum with dried BS is an effective means o f improving passive transfer of IgG in newborn calves.