U.S. Rep. Louise Slaughter (D-NY) and Sen. Dianne Feinstein (D-CA) have asked the Obama administration to clarify its position on antibiotic use in food animals.

In a letter to Agriculture Secretary Tom Vilsack, the lawmakers asked Vilsack to explain remarks he made Sept. 15 at a National Cattlemen’s Beef Association meeting.

Responding to a question about legislation Slaughter and Feinstein have proposed, Vilsack reportedly said the use of antibiotics in livestock production cannot be banned, adding “USDA’s public position is, and always has been, that antibiotics need to be used judiciously, and we believe they already are.”

Slaughter and Feinstein, in their letter, said Vilsack’s statements, taken out of context,  “highlight a common misperception about our legislation.”  They said their bill does not ban antibiotics in agriculture but would gradually phase out the use of seven antibiotics that are critical in human medicine.  The bill also calls for farmers to use antibiotics only under veterinary supervision and only for sick animals; antibiotics could not be used as a daily meal supplement in animals’ feed.

The bill, called the Preservation of Antibiotics for Medical Treatment Act, was introduced in 2009.  It calls for stricter measures than were recently urged by the Food and Drug Administration, which is merely asking for voluntary compliance.

Those draft FDA recommendations, released for public comment in June, were immediately questioned by industry groups.  But some say FDA’s proposed guidelines do not go far enough.

Slaughter and Feinstein, in the letter to Vilsack, asked whether USDA believes all antibiotics are used judiciously.  “USDA officials have publicly acknowledged the forty years of evidence suggesting the need to change antibiotic usage practices on farms,” they wrote.

They also pointed to a statement made by Dr. John Clifford, USDA chief veterinary officer,  during a July 14 hearing before the House Energy and Commerce Committee.  Clifford said then that USDA is “committed to identifying opportunities to reduce (antibiotic) usage and maintain the effectiveness of these drugs…through the development of new treatment options for animals…” 

According to estimates by the Union of Concerned Scientists, some 50 million pounds — 70 percent of antibiotics used in the United States each year — are mixed into animal feed or drinking water to promote growth or compensate for crowded conditions.  Meanwhile, there is growing evidence that the antibiotics in meat have led to antibiotic-resistant strains of bacteria and have already made some drugs ineffective.

In July, Dr. Thomas Frieden, director of the Centers for Disease Control and Prevention, told Congress that there is a clear link between antibiotic use in animals and antibiotic resistance in humans.

And Joshua Sharfstein, a deputy commissioner with FDA, told reporters in July that giving food animals antibiotics for nontherapeutic reasons was “an urgent public health issue…to preserve the effectiveness (of antibiotics), we simply must use them as judiciously as possible.”

Sharfstein added, however, that FDA thinks “things can be done voluntarily.” 

In their letter, Slaughter and Feinstein told Vilsack his comments to the Cattlemen’s association seemed to run counter to previous positions taken by department officials.  “We hope that you can provide us with reassurances that your off-the-cuff remarks were taken out of context, and that you remain committed to protecting human and animal health,” they wrote.

Late yesterday, Vilsack’s office  released this statement:  “USDA believes that antibiotic use should be used judiciously to slow the development of resistance in animals.  USDA believes livestock producers are good stewards, use antibiotics judiciously, but there are some bad actors, and continued use can develop resistance.  USDA wants to be a partner with Congress, producers and other federal partners to address this important issue.”