A surprising finding by a team of
Margie Lee, professor in the UGA College of Veterinary Medicine, and her colleagues have found that chickens raised on antibiotic-free farms and even those raised under pristine laboratory conditions have high levels of bacteria that are resistant to common antibiotics. Her findings, published in the March issue of the journal Applied and Environmental Microbiology, suggest that poultry come to the farm harboring resistant bacteria, possibly acquired as they were developing in their eggs.
"The resistances don't necessarily come from antibiotic use in the birds that we eat," Lee says, "so banning antibiotic use on the farm isn't going to help. You have to put in some work before that."
Bacteria swap genes relatively easily, and Lee explains that the concern is that drug resistance genes from bacteria that infect poultry could be passed on to bacteria that cause human illness. With these resistance genes, human bacterial illness could become harder to treat.
"This issue of antibiotic resistance is more complicated than once thought," Lee says. "These findings suggest that banning antibiotics at the farm level may not be as effective as assumed."