Transport Source, Housing, and Antibiotics Shape Veal Calf Microbiota

This study looked at two common problems in veal calf production: 1) Transport route: calves that are first moved to a collection centre (CC) before going to the veal farm, or those that are taken directly from the dairy farm (DF). And 2) Early-life antibiotics: giving all calves a single dose of antibiotics through the milk replacer on day 4 after arrival, or giving none. Design: 94 calves (89 bulls, 5 heifers), 2–4 weeks old, ~46 kg on arrival. 2 × 2 factorial: (CC + AB), (CC + no AB), (DF + AB), (DF + no AB). Followed for 8 weeks, with repeated sampling of feces, lung fluid, nasal swabs, blood, body weight and health checks.