PSVI-21 Evaluation of passive immunity transfer and performance of calves receiving different sources of immunoglobulins

Abstract

The efficiency in the passive immunity transfer (PIT) is directly associated with the production cost and productivity of the animals. When fresh maternal colostrum (FC) is not available, frozen colostrum or colostrum replacer (CR) are alternatives to avoid failures in PIT (FPIT). Thirty-nine Holstein calves were used in a randomized block design with gender, weight and date of birth as blocking effect, and distributed in treatments: 1) feeding of 10% BW of CF; 2) feeding of 10% BW of FC; 3) 1.5 dose of a CR (SCCL®, Saskatoon, Canada). Animals received 6L/d of milk until 56d of life when they were subjected to gradual weaning until the end of the study (63d). Feed intake and health was monitored daily, and weight and blood samples were weekly taken. The Brix value at 24h of life was higher in animals receiving maternal colostrum when compared to CR (FC: 9.52a; Frozen: 10.68a; CR: 8.23b; P < 0.01). The immunoglobulins intake was higher (P < 0.01) for calves fed with maternal colostrum (FC or Frozen), which may explain the differences observed in the apparent efficiency of absorption (P = 0.02). The colostrum protocols affected the serum IgG concentration assessed at 24h (FC: 26.65b; Frozen: 35.69a; CR: 16.93c; P < 0.01); however, no treatment resulted in FPIT, with values of serum IgG above 10g/L. Starter intake increased during the milk-feeding period (P < 0.01), with no effects of colostrum feeding. ADG was influenced by treatments (P = 0.01), with higher gains for calves fed FC, resulting in higher final BW (P = 0.04). During the milk-feeding period, plasma glucose and total serum protein were higher for FC than for CR calves, with no differences for calves fed frozen colostrum. Feeding FC resulted in heavier animals at weaning; however, the frozen colostrum and CR used in this study are adequate alternatives, with no FTIP observed.