B.FLT.0224 Live viral vaccines for bovine respiratory disease: BVDV-1 efficacy

Summary

​Bovine respiratory disease (BRD) is the most important cause of disease and death in Australian feedlot cattle. Infectious agents play a crucial role in the development of BRD along with other factors such as stress, animal genetics, and animal management. Epidemiological studies have shown that prior exposure of animals to the pathogens commonly implicated in BRD reduces the risk of cattle developing disease. These findings suggest that safe and efficacious vaccines are critical to reduce the impact of BRD in feedlot enterprises.
Due to the number of pathogens associated with BRD it would be expensive and time-consuming to develop specific vaccines for each pathogen. In addition, some types of vaccines are not suitable for single use at induction. As a result, the development of a flexible vaccine platform using genetic engineering has been undertaken. The platform is based on bovine herpesvirus 1 (BoHV-1 or IBR), one of the key BRD pathogens, as a vector to deliver genes encoding the immunological determinants of the other BRD pathogens. This project evaluated the first generation vaccine (2in1) which uses BoHV-1 to deliver the immunological determinant from bovine viral diarrhoea virus 1 (BVDV-1 or pestivirus) in vaccination/challenge studies.