March 13, 2007

Antibiotics in chicken feed for growth not cost-effective - US study
 

The widespread practice of adding antibiotics to chicken feed for growth promotion is not cost-effective, according to a study by researchers at the Johns Hopkins Bloomberg School of Public Health.

They found that increases in the size of antibiotic-fed chickens did not offset the added cost of the feed. Overall, farmers lost about one penny per antibiotic-fed chicken, according to the study. 

Jay Graham and Ellen Silbergeld, both of the Bloomberg School's Centre for a Liveable Future, and John Boland, professor emeritus in the Whiting School's Department of Geography and Environmental Engineering, analysed the marginal profits associated with drug additives in comparison to the costs of utilizing these drugs. The data used in the analysis were compiled by the Perdue Corporation, a leading broiler-poultry producer. In 2002, Perdue discontinued use of antibiotics in its poultry.

The results of the economic analysis indicated that the net effect of using growth-promoting antibiotics in feed was a loss of $0.0093 per chicken, or about 0.45 percent of the total cost per chicken. The results do not include potential changes in veterinary costs from switching to antibiotic-free feed or medical and public health costs incurred from treating antibiotic-resistant illnesses.

Graham, lead author of the study and a doctoral student in the Bloomberg School's Department of Environmental Health Sciences said that although Perdue has discontinued the use of growth-promoting antibiotics, the study will remain relevant globally and in the US as roughly two-thirds of 8.7 billion broiler chickens raised in the country are fed antibiotics throughout their life. Internationally, he said, poultry production is growing rapidly mostly in developing countries where there are limited controls on antibiotic use for animals.

Graham stressed the results of the study help dispel the myth that growth-promoting antibiotics are vital to raising poultry.

According to Silbergeld, co-author of the study and a professor in the Bloomberg School's Department of Environmental Health Sciences, the public health community has long had concerns about the potential misuse of antibiotics in food animal production.

The antibiotic practice has been associated with the dangerous increases in the number of antibiotic-resistant infections in people worldwide, she said.

Silbergeld concluded the study has considered the economic costs and benefits of antibiotic feed additives and its results should make the industry rethink its usual practices from a business perspective.