Seven of 24 zookeepers exposed to a Southern white rhinoceros infected with Mycobacterium bovis were presumably infected via aerosols generated in the cleaning of the barn for the rhinoceros. All demonstrated conversion by the intermediate-strength purified-protein-derivative skin test, but none had clinical illness. In certain occupational settings like zoos and abattoirs, exposure to M. bovis may be an occupational hazard, and routine periodic tuberculin screening should be performed.