Reseachers find antibiotic chicken feed not a necessity
Meat from chickens raised on organic feed is likely just as safe as meat from chickens eating antibiotic-laden grub, a University research team reports.
"We tested 456 samples (from chickens given either organic or traditional, antibiotic-laced feed), looking for campylobacter and salmonella bacteria," said Patricia K. Welch, professor of animal science, food and nutrition.
"We found no cases of campylobacter, regardless of feed type. While we did find nine cases of salmonella, only three of those occurred among chickens on the organic feed, while six were found in the traditionally fed chickens," she said.
Although this is a relatively small study focusing on free-range chickens and those raised outside in movable pens (as opposed to chickens reared in "factory" farms), Welch believes these results are significant.
"They suggest that farmers raising chickens on a small scale don't need the antibiotics that are put into traditional feed in order to have a safe product," she said.
"This is a good thing, because there is growing concern about developing drug-resistant bacteria through the use of antibiotics in animal feed. It also means farmers can safely tap into organic specialty markets, where prices are higher."
The yearlong project, paid for with a $50,000 grant from the Council on Food and Agricultural Research, focused on campylobacter and salmonella because those two frequently turn up in raw chicken.
"According to the Centers for Disease Control, last year campylobacter caused 2.4 million cases of food-borne illness and salmonella caused 1.4 million cases," she said.
The feed study, conducted last year by Welch, faculty colleague Jeannette M. Endres and Benjamin A. Shepherd, a retired zoology professor, involved both free-range and pasture-caged chickens.
All were tested for campylobacter and salmonella as day-old brood chicks to insure they were free of disease at the study's start. When they reached market stage, Welch chose 35 chickens randomly from each farm for repeat tests. At the processing plant, line workers removed the innards from each of the designated chickens and turned them over to the researchers who bagged them and analyzed them at a Centralia laboratory.
"We found there was no significant feed effect, which means that you may not need the antibiotics that are traditionally put into feed, though I must emphasize that this study did not include a comparison with large commercial operations," Welch said.
"It also didn't matter whether the chickens were free range or pastured in terms of producing a product that was relatively free of infection."
Welch said these results suggest further farm studies aimed at pinpointing the critical production stages where contamination is most likely to occur. As for the research team, it has received a second CFAR grant for work focusing on poultry safety in grocery stores.
"We want to pull chicken off the shelves to test for salmonella and campylobacter," Welch said. "Food-borne bacteria cause 76 million illnesses, 325,000 hospitalizations and 5,200 deaths in this country each year. Identifying the hazard points and developing methods to prevent or reduce contamination is key in reducing the incidence of these illnesses."
- K.C. Jaehnig
March 6, 2002