Pneumogen-5 vaccine, an inactivated polyvalent vaccine (BVD- genotypes 1 and 2, IBR, PI-3, and BRS viruses), was prepared for control of respiratory diseases producing great losses to calves. It was tested for quality and then applied in pregnant cattle 8 weeks before calving for evaluation of their humeral immune response under field conditions. The prepared vaccine was able to induce detectable protective levels of specific antibodies for all reference viruses contained in the vaccine by the 2nd week post vaccination (6 weeks pre-calving period) and continued till 4 month post-calving as measured by SNT and 6 month post- calving by ELISA. Protective levels of specific antibodies were detected in colostrum persist at their higher level till the 3rd day post calving for all reference viruses contained in the vaccine as measured by SNT and confirmed by ELISA. It is concluded that the prepared vaccine was highly potent and provided good colostrum immunity that can protect newborn calves. |