Livestock drug restrictions likely moot in Az

PHOENIX – Proposed federal restrictions on the use of certain antibiotics in livestock and poultry wouldn’t have much an effect on Arizona’s farms and ranches, according to experts here.

That’s because the class of antibiotics in question isn’t used widely in Arizona – or elsewhere in the U.S., they say.

The Food and Drug Administration restrictions, which are scheduled to take effect in April after a comment period, address use of cephalosporins in cattle, swine, chicken and turkeys beyond approved uses listed on the label. The goal: maintaining the drugs’ effectiveness in humans by preventing antibiotic-resistant bacteria.

“This is FDA’s attempt to try and prove and say that they’re basically doing something about it, but the overall impact is really not going to be that great at this point,” said Dr. Peder Cuneo, extension veterinarian at the University of Arizona.

“There are other antibiotics that are more effective,” said John Marchello, a professor at the University of Arizona’s Department of Animal Sciences. “To my knowledge, it’s not used that much.”

Dr. Perry Durham, state veterinarian with the Arizona Department of Agriculture, said the so-called “extralabel” use of approved antibiotics is a frequent practice in the agricultural sector. Those include using different dosages and frequencies as well as using drugs for animal conditions other than listed on the label.

“Most of the medications we use in the large-animal world do not have specific approvals for the specific things they are used for,” he said.

Such uses must be under the supervision of a certified veterinarian and are allowed only for FDA-approved drugs, according to an American Veterinary Medical Association fact sheet.

Cephalosporins are commonly used to treat pneumonia in cattle. For humans, they’re used for pneumonia, skin and tissue infections and pelvic inflammatory disease.

Of the nine domestic antimicrobial drugs approved for use in animals, cephalosporins were the least widely distributed and sold in 2010, according to an FDA summary report.

“It’s something that’s not common,” said Dr. Alyn McClure, a veterinarian whose clients include members of the Arizona Farm Bureau. “But apparently somebody’s misused it, otherwise they wouldn’t be trying to enforce these restrictions.”

In 2008, the FDA proposed similar restrictions on the use of cephalosporins in food-producing animals but withdrew them due to opposition from drug companies, farmers and veterinarians.

Siobhan Delancey, public affairs officer for the FDA, said in response to emailed questions that while cephalosporins aren’t as widely used in agriculture as other medicines they are a particularly important in treating humans.

“If cephalosporins are not effective in treating these diseases, doctors may have to use drugs that are not as effective or that have greater side effects,” she wrote.