Feeding antibiotics to chickens provides no economic benefit.
An estimated 70 percent of all antibiotics sold in the United States—more than 24 million pounds every year—are used on farms, mostly in animal feed. Health researchers have long worried that this heavy load of antibiotics is causing strains of bacteria to evolve that are impervious to the drugs.
Farmers have justified their practice on the grounds that antibiotics help fatten up the birds, thereby increasing profits. But a groundbreaking study (pdf) by Johns Hopkins Bloomberg School of Public Health pulls the rug out from under this argument.
Using data collected by Perdue poultry farms, Hopkins researchers calculated that Perdue lost $.0093 per broiler chicken when using antibiotics.
For each dollar spent on antibiotic feed additives, the return was less than 10 cents. “We were surprised to find no measurable benefit and actually a business loss.” [Discover story]