Consumers Uniocattle-feedlot.jpgn, the nonprofit publisher of Consumer Reports, and the Food Animals Concern Trust (FACT), a Chicago-based animal welfare organization, presented a petition signed by 37,000 people to the U.S. Food and Drug Administration (FDA) Friday asking the agency to ban the practice of feeding poultry waste to cattle.

Poultry waste, known as “poultry litter” is generally comprised of feces, sawdust, feathers, spilled feed, and anything else that might accumulate on the floor of a chicken or turkey coop. The byproduct is added to livestock feed because it has nutritional value and it is cheap.

The FDA estimates that cattle are fed between 1 and 2 million tons–several billion pounds–of poultry litter annually.

“It seems ghoulish, but it is a perfectly legal and common practice,” said Michael Hansen, PhD, a senior scientist with Consumers Union.

According to Consumers Union, in addition to the mix of feathers and feces, poultry litter can contain “disease-causing bacteria, antibiotics, toxic heavy metals, restricted feed ingredients including meat and bone meal from dead cattle, and even foreign objects such as dead rodents, rocks, nails and glass.”

The consumers groups believe feeding poultry litter to cattle presents a serious risk to human and animal health. 

“The resulting health threats include the spread of mad cow disease and related human neurological diseases, the development of antibiotic resistant bacteria, and the potential for exposure to toxic metals, drug residues, and disease-causing bacteria,” said Consumers Union in a news release.

“The FDA must step in and ban poultry litter as cattle feed once and for all,” said Richard Wood, FACT’s executive director. “Feeding chicken feces to cows is unfortunately not some poorly considered Halloween prank–it is an everyday practice in feedlots. Cows deserve better than toxic leftovers.”

Eleven national organizations endorsed the petition, including the Center for Science in the Public Interest (CSPI). McDonald’s Corp., the nation’s largest beef purchaser, also wants the FDA to ban the practice.

The National Cattlemen’s Beef Association (NCBA), a powerful trade group for the beef industry, said the ban is not necessary.

“Science does not justify the ban, and the FDA has looked at this now many times,” Elizabeth Parker, NCBA’s chief veterinarian told the Los Angeles Times.

The FDA has until November 11, 2009 to respond to the petition.