Bovine respiratory disease (BRD) — commonly called "pneumonia" — is the most economically significant disease of housed cattle in the UK and a major welfare concern. It causes substantial suffering, high treatment costs, impaired growth, and significant mortality, particularly in calves and youngstock.
BRD is typically a multifactorial disease involving an interaction between: respiratory viruses (BVD, IBR, RSV, PI3), secondary bacterial pathogens (Mannheimia haemolytica, Pasteurella multocida, Histophilus somni), and host immune function. Stress — from transport, mixing, weaning, or housing — suppresses immune function and creates the window of vulnerability that pathogens exploit. No single agent causes BRD in isolation.
BRD causes significant and often prolonged suffering: fever, difficulty breathing, reduced feed intake, depression, and in severe cases, pleuropneumonia with associated chronic pain. Many affected animals are not identified until disease is already advanced. Sub-clinical BRD (below the treatment threshold) may affect 30-40% of beef cattle at housing, causing reduced growth and immune compromise without visible signs.
Early antibiotic treatment of BRD significantly improves welfare outcomes and reduces treatment failure. Systematic daily monitoring (DART scoring system: Depression, Appetite loss, Respiratory signs, Temperature) enables early identification. Prompt, appropriate antibiotic treatment under veterinary guidance — paired with NSAID analgesia — is the welfare-appropriate response to confirmed BRD cases.