The government wants meat and poultry producers to stop giving antibiotics to their animals to make them grow faster.
The reason: Dangerous bacteria that can kill people have been growing resistant to the drugs, which can leave humans at risk of getting infections that can't be controlled.
The announcement on Wednesday by the Food and Drug Administration, which asks producers to make the change voluntarily, comes two years after the agency declared that using antibiotics in food-producing animals "is not in the interest of protecting and promoting the public health."
"This is a sea change," says Michael Taylor, the FDA's deputy commissioner for foods. "We're finally ready to put this issue behind us."
Skeptics fear the animal pharmaceutical industry will make only cosmetic changes and the meat producers will continue using feed with antibiotics.
"They'll just stop marketing drugs as growth promoters and instead market them for disease prevention at exactly the same doses and same period of use," says Steve Roach with the Food Animal Concerns Trust in Chicago.
Antibiotics have been added to animal feed and water since the 1960s, when it was found that very low, long-term doses not only kept animals from getting sick but also made them grow faster.
Concerns about bacteria becoming resistant to those antibiotics -- often the same ones used to treat human disease -- began in the 1970s.
The FDA tried to restrict their use in 1977, but Congress opposed the restrictions. The agency, doctors, farmers and activists have been fighting about the issue ever since.
The new guidance asks, but does not require, that companies stop selling antibiotics medically important in human disease as growth promoters for animals.
Two commonly used ones would be penicillin and tetracycline, says William Flynn, deputy director for science policy at the Center for Veterinary Medicine at the FDA.
Antibiotics could still be given to sick animals, but feed containing antibiotics would have to be prescribed by a veterinarian.
Jeff Simmons, president of Elanco, a large animal pharmaceutical company in Greenfield, Ind., agrees with the the FDA's move. Putting antibiotic use "under the oversight of the veterinarian is critical," he says.
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