PSIII-13 - The effect of the inclusion of liquid brewers yeast during gestation on colostrum quality and passive transfer of immunity in lambs

Fourteen Suffolk/Suffolk x Hampshire pregnant ewes were utilized to evaluate the effects of liquid brewers yeast on colostrum quality and the transfer of passive immunity in their offspring. Parainfluenza type 3 (PI3) vaccination was used elicit an immune response. Ewes were vaccinated with PI3 at 33 and 18 d prior to expected lambing day. Ewes were randomly assigned to one of two treatments: late gestation diet (CON) or late gestation diet supplemented with liquid brewers yeast at an average rate of 60 g DM/d (LBY). Ewes were fed treatment diets from 45 d prior to expected lambing to 3 d post lambing. Blood was collected from ewes’ via jugular venipuncture prior to vaccination and within 6 hours postpartum. Blood was collected also from the jugular vein of lambs (n = 22) at 3 d of age. Ewe and lamb blood serum was tested for Bovine Parainfluenza 3 Virus and data on anti-PI3 antibody titers was evaluated. Colostrum was collected within 4 hours postpartum and analyzed for colostral IgG concentrations using a refractometer in % Brix. A PROC GLM model was performed in SAS 9.4, where the model for ewe colostrum quality and lamb anti-PI3 titers analyses included the main effect of treatment diet. All vaccinated ewes were positive for PI3 antibodies ( >64 titer) immediately prior to and post lambing. All lambs tested positive for antibody titers for PI3 with no differences between treatment (197.3 for CON and 160.8 for LBY; P = 0.43). The colostral IgG concentrations did not differ between CON (30.4% Brix) and LBY (24.6% Brix) ewes(P = 0.21). These results indicate that, although there were numerical differences, the addition of LBY to the ewes’ diet during late gestation did not significantly improve colostrum quality or passive transfer of immunity in lambs.