Livestock

Bovine Respiratory Viruses: Welfare and Vaccination

How BHV-1, BRSV, and PI3 contribute to bovine respiratory disease and how vaccination prevents welfare harm.

Key Facts

BHV-1 (IBR), BRSV, and PI3 are the primary viral pathogens of bovine respiratory disease
Viral infection alone rarely causes severe disease — it predisposes to bacterial superinfection
Vaccination before stress events reduces the frequency and severity of respiratory welfare emergencies
Marker vaccines allow differentiation of vaccinated from naturally infected animals in IBR control programmes

Welfare Considerations

Bovine respiratory viruses cause immunosuppression that enables secondary bacterial pathogens to cause severe pneumonia. Welfare-focused vaccination targets key viral antigens before anticipated stress events — mixing, weaning, or transport. Timing is critical — vaccination shortly before stress has less protective effect than pre-event vaccination. IBR marker vaccines support national eradication programmes that offer long-term welfare benefits.

What You Can Do

Vaccinate cattle against key respiratory viruses at appropriate intervals before stress events
Discuss IBR marker vaccine use with your vet if your area has an eradication programme
Time vaccination programmes to ensure protective immunity has developed before anticipated stress