(NEW YORK) -- Even though Ross Kiehne keeps his patients in top physical form, they all have only six months to live. That's because Kiehne is a swine veterinarian, and his patients are, well, your Christmas hams. The U.S. Food and Drug Administration hopes that livestock vets such as Kiehne will soon become the gatekeepers for antibiotics in animal feed, keeping the public safe from antibiotic-resistant bacteria.
The third-generation Minnesota farmer treats his patients with antibiotics only if the animals are sick or have been too near contagious animals. He doesn't give healthy animals the over-the-counter, low-dose antibiotic feed commonly known to promote growth -- a practice the FDA hopes to phase out in three years.
"It goes right along with the way I work with my clients," Kiehne told ABC News. "I think it elevates our importance in the area of insuring animal health and ultimately food safety."
Unlike doctors who treat people, veterinarians take an oath that includes not only caring for their animal patients but ensuring overall public health, Pew Charitable Trusts health expert Gail Hansen told ABC News.
Salmonella, for example, doesn't make chickens sick, but vets worry about it because it makes people sick, Hansen said. As a result, vets want to avoid creating antibiotic-resistant salmonella by prescribing antibiotics to chickens only when absolutely necessary.
But farmers, who own the animals and don't have to take veterinarians' advice, have been giving healthy animals over-the-counter antibiotics to make them grow faster for years.
"Nobody knows exactly why, but giving very low doses of antibiotics makes animals grow faster -- probably because of changes in the character of bacteria in the animals intestinal systems," said Hansen, a former practicing veterinarian and public health official in Kansas.
Animal guts are like petri dishes for superbugs when long-term antibiotics are involved, infectious disease experts say.
"In effect, all these animals have been just like a test tube in which we have been creating resistant bacteria," said Dr. William Schaffner, a former president of the National Foundation for Infectious Diseases.
Schaffner, chairman of preventive medicine at Vanderbilt University Medical Center, said once the animals are slaughtered, the superbugs wind up on meat and in people's kitchens. If consumers aren't following the proper food safety rules -- washing surfaces and heating food to the right temperatures -- those bugs can make them sick.
This is why the FDA called on animal pharmaceutical companies to voluntarily change the labels on antibiotic feed products, eliminating their FDA-approved use as a growth promoter. Companies have 90 days to declare their intent to do so, and three years to make the label changes.
Once the labels change, it would become illegal to feed these antibiotics to animals without the approval of a veterinarian for a medical reason.
Critics say the plan won't work because the label changes aren't mandatory, and farmers could potentially find loopholes.
According to the U.S. Department of Agriculture, more than seven million chickens, 92,000 hogs and 26,000 cattle have been slaughtered and inspected in the United States from January through October of this year.
But there is no data on how many of these were seen by vets before they were slaughtered, Hansen said.
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