Current concepts in dairy cattle vaccinology

Abstract

Vaccination is an important component for the prevention and control of disease in the dairy herd. Modified-live vaccines (MLV) have been used because of the good antibody response, longer duration of immunity, fewer doses needed per animal, and lower cost. N on-adjuvanted MLV vaccines fail to booster well-vaccinated animals, as active vaccine-induced immunity neutralizes vaccine virus preventing the MLV from replicating and preventing a booster immune response. Improved adjuvants have increased the scope and duration of inactivated virus immunity. Prepartum vaccination aimed at colostrum development is critical. Inactivated viral vaccines aimed at reproductive disease have greatly improved and should be considered to be given in the dry period to provide maximum conception rate during the fresh period. The periparturient period (the last 3 weeks prior to calving and the first 3 weeks following calving) are poor times to initiate an immune response-hormonal, dietary and metabolic factors limit immune responsiveness. Post-partum is also a difficult time to vaccinate, as lactation energy demand supersedes immunity. Each vaccine program needs to be designed based on animal flow, actual "disease" threats, and labor on the farm.