groups are asking a court to force a ban by the federal agency. Steve Roach is with the group Food Animal Concerns Trust, or FACT.

STEVE ROACH: "As far as we can tell, all they were trying to do was kindly ask the industry to make changes. And we just do not believe that is [an] adequate response."

His group wants the government to ban the use of two common antibiotics at levels below those used to treat sick animals.

STEVE ROACH: "After thirty years, I think it is time for someone to put a little more pressure on them. And that is what the aim of the lawsuit is."

Supporters of low-level antibiotic use in animals say there is no solid evidence linking it to drug-resistant infections in humans. They also say that in addition to increasing growth, the drugs help suppress diseases in animals confined together in large feeding operations.

Ron Phillips is with the Animal Health Institute, a trade group for the animal-drug industry. He says suppressing animal disease means a safer food supply.

RON PHILLIPS: "Sicker animals result in greater contamination on the meat. So the way to control pathogens on the farm, so that they do not transfer through the food chain, is to make sure we have healthy farm animals."

Experts say the largest source of resistant bacteria is the overuse and misuse of antibiotics among people.

And that's the VOA Special English Agriculture Report, written by Jerilyn Watson and Steve Baragona. You can read, listen and learn English with our programs and activities at voaspecialenglish.com. I'm Bob Doughty.