Last year, in the wake of the biggest beef recall in history linked to a Southern California slaughterhouse, inspectors visited the Fresno facility and 17 other plants that sold meat to the National School Lunch Program.
Inspection records from March 2008 show U.S. Department of Agriculture auditors found workers in Fresno were using electric prods to coax skittish cattle through a narrow chute leading into the slaughterhouse.
When three cows refused to budge, they were stunned and rendered unconscious "so that they could be pulled through the restrainer to be shackled, hung and bled," the records state.
The USDA considers electric prods a humane tool when they are used properly on walking animals.
But dragging unconscious cattle could increase the risk for E. coli and salmonella contamination because cow hides can pick up bacteria from feces that sometimes collect in or around the chute, experts said.
"All kinds of feces and urine get into those chutes because they typically aren't cleaned out during the day because too many animals need to get in," said Lester Friedlander, a former USDA veterinary inspector.
The plant's parent company, Cargill Meat Solutions, said the animals balked because there were too many auditors present that day. The company appealed the alleged violation. The USDA's Food Safety and Inspection Service later rescinded the citation and instead sent Beef Packers a letter of concern.
Dan Thomson, a professor with Kansas State University's Beef Cattle Institute, defended Cargill's food safety record, and said he believed problems with humane handling did not cause contamination at the Fresno plant.
"It wasn't clear that these cows were drug long distances across dirty floors. They may have just been moved a few feet," Thomson said. "A lot of animal hides get contaminated on farms, or in transport to the abattoir."
Agency spokeswoman Bryn Burkard said a Freedom of Information Act request would have to be made to learn if the plant had been inspected since.
Neither the USDA nor Cargill have provided details about what caused last week's recall of hamburger meat. Cargill is working with retailers to ensure that all the recalled beef is removed from retail distribution centers in Arizona, California, Colorado and Utah, spokeswoman Rebecca Hayne said.
The USDA said California, Colorado and Wyoming have reported illness linked to the recalled beef.
Colorado health officials said 21 people there have been sickened, and all are recovering. California officials said five people have reported feeling sick, and two fell ill in Wyoming.
Salmonella can result in abdominal cramps, diarrhea and fever. Most people recover without treatment, but some require hospitalization. In rare cases the organism can get into the blood and produce more severe illnesses.
