143 The Effects of Vaccination Strategies on Bovine Viral Diarrhea Virus Antibody Titers and Body Weight Performance in Pre- and Post-weaned Beef Calves

Abstract

Abstract The Oklahoma Quality Beef Network utilizes three health protocols for producer choice based on vaccine timing and viral components. The study objective was to examine the effects of vaccine type and timing on animal performance, and immune response pre-and post-weaning. A total of 151 Angus, Angus x Hereford, or Angus x Charolais calves were randomly assigned to one of three health protocols stratified by breed of sire, sex, and date of birth. Vaccination treatments were 1) KV/MLV – multivalent inactivated BRD vaccine (KV) administered on d 0 and revaccination with a pentavalent modified-live virus on d 125; 2) MLV/MLV – pentavalent modified-live virus on d 0 and d 125; or 3) WEAN – pentavalent modified-live virus on d 125 and 139. Virus-specific antibody (Ab) titer data was determined using serum-neutralization from serum collected at six time points. Antibody titers, BW, and ADG variables were evaluated following vaccination. Results indicated there was no treatment effect on BW. Bovine viral diarrhea virus (BVD) also displayed significance for treatment x date interaction. The MLV/MLV provided greatest response from d 0 (branding) to d 125 (weaning) than the other two treatments. There was no difference between the KV/MLV group and the WEAN group from d 0 to d 125. By d 167 the KV/MLV group had a greater immune response than the MLV/MLV and WEAN groups. The MLV/MLV provided the greatest protection from branding to weaning. Providing a KV at branding had minimal effect on BVD titers but responded well to MLV vaccine at weaning by d 167. The WEAN group generated the least number of titers overall. Further investigation is needed to determine the long-term protection of vaccination strategies.