Cattle Respiratory Syncytial Virus Welfare

Bovine respiratory syncytial virus (BRSV) is a major cause of severe respiratory disease in young cattle, with vaccination providing protection against this welfare-significant pathogen.

Key Facts

BRSV is a major component of the bovine respiratory disease complex, particularly in calves
The virus causes severe bronchiolitis with breathing difficulty, fever, and wheezing
Calves between 2-6 months are most susceptible when maternal antibody levels are declining
Severe BRSV can cause acute respiratory failure and death in young calves
Vaccination is available and reduces disease severity when properly timed before exposure
Weather changes and autumn turnout to housed calves represent high-risk exposure periods
Secondary bacterial pneumonia is a common complication of BRSV infection

Welfare Considerations

BRSV causes severe respiratory distress that is clearly distressing for affected calves. The bronchiolitis caused by BRSV makes breathing laborious and inefficient, with calves showing visible respiratory effort. Acute BRSV can cause rapid deterioration requiring intensive supportive care. The disease is most severe in young calves in their first winter, when respiratory stress from housing combines with declining maternal immunity. Vaccination programs that protect against BRSV, along with other key respiratory pathogens, are a straightforward welfare investment that prevents significant suffering during the vulnerable autumn housing period.

What You Can Do

Implement vaccination programs targeting BRSV in calves before their first housing period
Monitor calves closely during and after housing for early signs of respiratory disease
Ensure housing ventilation is adequate to reduce respiratory pathogen concentration
Begin BRSV treatment promptly with supportive care and anti-inflammatories when detected
Consult your vet about appropriate BRSV vaccination timing and products for your calf population
Reduce housing stress through appropriate group sizes and avoiding unnecessary mixing