Bovine respiratory disease complex is the most economically and welfare-significant disease affecting feedlot and dairy cattle globally.
Cattle with BRD experience fever, respiratory distress, pain from pneumonia, and the debilitating effects of systemic illness. The high stocking densities and frequent commingling of feedlot environments facilitate rapid respiratory pathogen spread. Daily animal observation by trained staff is essential for early disease detection, as cattle hide illness. Delayed treatment allows progression to chronic pneumonia causing permanent lung damage and persistent poor welfare. Metaphylactic treatment programs, while raising antibiotic resistance concerns, can prevent disease outbreak in high-risk groups. Welfare and antibiotic stewardship goals are best reconciled through improved housing, reduced commingling stress, and better diagnostic monitoring.