Antibiotic resistance in bacteria from magpies (Pica pica) and rabbits (Oryctolagus cuniculus) from west Wales

The prevalence of antibiotic-resistant bacteria in wild animal and bird pop ulations is largely unknown, with little consistency among the few publishe d reports. We therefore examined intestinal bacteria from magpies (Pica pic a) and rabbits (Oryctolagus cuniculus) collected in rural west Wales. Esche richia coli isolates resistant to multiple antibiotics were grown from eigh t of 20 magpies trapped in spring, 1999 and one of 17 in spring, 2000; the most prevalent resistance trait among these isolates was to tetracycline, b ut resistances to ampicillin, chloramphenicol, kanamycin, sulphonamide, tet racycline and trimethoprim were also found. Tetracycline-resistant Enteroco ccus spp. were found in one of 20 magpies in 1999 and three of 17 in 2000. Only one resistant E. coli isolate was detected among gut bacteria from 13 rabbits, and this strain was resistant only to tetracycline. Differences in the prevalence of resistance between bacteria from rabbits and magpies may reflect differences in diet: rabbits graze field edges, whereas magpies ar e omnivorous and opportunistic. The resistance genes found in E. coli isola tes from magpies mostly corresponded to those common among human isolates, but those conferring tetracycline resistance were unique.