This project investigates the impact of infections with bovine respiratory syncytial virus (BRSV) and bovine corona virus (BCV) in dairy herds on overall disease burden in the herd, usage of antibiotics, prevalence of antibiotic resistances and herd productivity. The aim is to document the potential benefits of mitigating spread of BRSV and BCV in dairy herds.
Our hypothesis is that the overall burden of disease is higher in herds were BRSV and BCV are present thjan in herds free from these viruses. As a consequence the usage of antibiotics is higher in herds with BRSV and BCV which in turn leads to a higher prevalence of antibiotic resistance. A higher disease burden also has a negative impact on herd productivity by e.g. higher calf mortality, suboptimal growth and suboptimal fertility.
In the project, 50 herds free of BRSV/BCV and 50 herds where these viruses occur will be compared with respect to occurrence of disease, use of antibiotics, occurrence of resistance and production.