Staphylococcus aureus strains from human nasal carriers without vocational contact with pigs could be differentiated from the majority of strains obtained from pathologically affected pigs by determination of host-specific-variety, according to Meyer (1966) and Witte et al. (1977). Less unambiguous findings regarding site variability were recorded from strains in nasal mucosa of pig-handling personnel, clinically intact pigs on farms, and slaughtered pigs. Antibiotics, such as oxytetracycline and macrolides were applied to pigs but failed for all practical purposes to have any bearings on the development of Staphylococcus aureus resistance in human probands with no vocational contact with animals. Personnel of pig units, however, exhibited moderate resistance to oxytetracycline and macrolides of Staphylococcus aureus strains which were typical of man. Macrolide resistance was determined, in that context, by one single-resistance plasmid.