Cows wait to be milked at a farm in Escalon, Calif. in 2009. Justin Sullivan/Getty Images

A panel convened by Johns Hopkins University to assess antibiotic use in livestock has warned that the United States faces unnecessary public health risks because of the too-frequent use of antibiotics in chickens, cows and pigs, as well as the Food and Drug Administration’s alleged lack of action on the issue.

"Meaningful change is unlikely in the future," the 14-member panel concluded in a report that was released Tuesday and quickly drew protests from livestock industry groups.

Antibiotics are routinely sprinkled into U.S. cattle, hog and poultry feed to promote growth, and are also used to prevent and treat illness. Agriculture accounts for 80 percent of antibiotic sales, according to the limited records available.

The report’s release came on the fifth anniversary of a landmark 2008 Pew Charitable Trust report that called for livestock producers to stop using antibiotics unless their animals are sick, and to no longer use tiny cages for egg-laying hens. That report claimed that antibiotic overuse would lead to antibiotic resistance within the U.S. population, which could increase the prevalence of illness.

Congressional hearings followed the release of that report, prompting an intense defensive response from the livestock industry.

The new Johns Hopkins report said that "additional scientific evidence has strengthened the case that these (non-therapeutic) uses pose unnecessary and unreasonable public health risks" of allowing bacteria to develop resistance to antibiotics.

"We have even better science to support the recommendations we have made," Mary Wilson, an epidemiologist at Harvard University, said according to Reuters. "We are, in fact, running out of antibiotics. We are seeing infections that are untreatable."

More than 2 million Americans are sickened by antibiotic-resistant infections each year and 23,000 of them die, according to the U.S. Centers for Disease Control and Prevention.

Livestock industry leaders said the new report did not provide a clear link between antibiotic use in livestock and the rise of antibiotic-resistant illness in humans.

Critics of antibiotic use are "just pushing a pre-set agenda," said Scott Hurd, an associate professor at Iowa State University who works on risk assessment.

They tied drug-resistant bacteria strains to overuse of antibiotics by people.

However, Robert Lawrence, director of the Johns Hopkins Center for a Livable Future, which produced the report, blamed "the political power of industrial agriculture" for lack of action on antibiotics and other reforms.

Legislation to expand the U.S. Food and Drug Administration's power over antibiotics use in livestock has stalled repeatedly in Congress.

"Antibiotics were invented to cure sick humans, not to compensate for unsanitary conditions on the farm or fatten animals up so they could sell for more at the market," New York Rep. Louise Slaughter told Reuters.

Al Jazeera and Reuters