Reducing the over-use of preventative antibiotics in animal production to limit the spread of antimicrobial resistance is important for public health and animal health. We explore how supply chain relationships influence the incentives for beef farmers to engage in production practices, including antibiotic use, that are optimal from public and animal health perspectives. We examine the case of the French young bull sector, where animals are gathered, mixed, and transported over long distances, increasing the risk of developing the bovine respiratory disease (BRD). Interviews with economic actors in the French young bull sector reveal how transaction costs and patterns of vertical coordination influence the incidence of BRD and the preventative use of antibiotics. Dispersed supply chains with low levels of vertical coordination inhibit information flows about vaccination status and reduces incentives for cow-calf producers to adopt optimal animal health management practices.