R plasmid-mediated gentamicin resistance in salmonellae isolated from turkeys and their environment.

Gentamicin-resistant salmonellae were isolated from turkey poults, hatching eggs, and litter on three unrelated farms and from a scrub jay (Aphelocoma coerulescens) on a fourth farm unrelated to the other three. The isolates were Salmonella arizonae from three of the farms (poults, eggs, scrub jay) and S. thompson (litter) from the fourth farm. The genes responsible for gentamicin resistance were located on the same conjugal plasmid. This plasmid also encoded resistance to kanamycin, streptomycin, ampicillin, and sulfadiazine.