LOS ANGELES — An undercover video showing crippled and sick animals being shoved with forklifts has led to the largest beef recall in the U.S. and a scramble to find out if any of the meat is still destined for school children's lunches.

The U.S. Department of Agriculture on Sunday ordered the recall of 143 million pounds of beef from a Southern California slaughterhouse that is the subject of an animal-abuse investigation.

The Wake County school system received about 35,000 pounds of the recalled beef, spokesman Bill Poston said. About 5,200 pounds of that was distributed to area schools, but none of it was served to students, he said.

The meat – it was in the form of beef patties and in chili and spaghetti sauce – has been on hold from use for the past three weeks, when USDA inspectors first noticed a problem at the slaughterhouse, Poston said. Most of the recalled beef Wake schools had received was still in the district's warehouse, he said.

"What we have in our freezer will be destroyed," said Marilyn Moody, child nutrition service senior director for Wake County schools. "It's rare that a product is recalled, but again, we have numerous agencies that notify us."

Recalled beef also turned up in Johnston and Orange counties.

School in Johnston County consumed about 85 pounds of the meat in November, district spokeswoman Crystal Roberts said. No illnesses have been reported.

Recalled beef was processed for Chapel Hill-Carrboro City Schools and has been placed on hold in recent weeks, spokeswoman Stephanie Knott said. None of the beef was served to students, she said.

School districts in Durham and Cumberland counties contract with other suppliers and were unaffected by the recall, officials said.

Some parents said the Wake district's swift action to respond to the recall was reassuring.

"Accidents do happen, and I'm sure that (with) as much food is processed and has to go through the school system, there's a possibility that could happen," parent Corey Little said. "(It) would be a little more comforting to know that it was caught."

The recall will cost Wake County schools $94,489, and district officials said they would try to recoup that cost through a refund or replacement products.

"These are our babies. We are going to feed them the right way," said Kathryn Grady, assistant food service manager at Barwell Road Elementary School in Raleigh.

The recall affects beef products dating to Feb. 1, 2006, that came from Chino-based Westland/Hallmark Meat Co., the federal agency said. The company provided meat to various federal programs.

Secretary of Agriculture Ed Schafer said his department has evidence that Westland did not routinely contact its veterinarian when cattle became non-ambulatory after passing inspection, and not doing that violated health regulations.

"Because the cattle did not receive complete and proper inspection, Food Safety and Inspection Service has determined them to be unfit for human food and the company is conducting a recall," Schafer said in a statement.

A phone message left for Westland president Steve Mendell was not returned Sunday.

Agriculture officials said the massive recall surpasses a 1999 ban of 35 million pounds of ready-to-eat meats. No illnesses have been linked to the newly recalled meat, and officials said the health threat was likely small.

Officials estimate that about 37 million pounds of the recalled beef went to school programs, but they believe most of the meat probably has already been eaten.

"We don't know how much product is out there right now. We don't think there is a health hazard, but we do have to take this action," said Dr. Dick Raymond, USDA undersecretary for food safety.

Federal officials suspended operations at Westland/Hallmark after an undercover video from the Humane Society of the United States surfaced showing crippled and sick animals being shoved with forklifts.

Two former employees were charged Friday. Five felony counts of animal cruelty and three misdemeanors were filed against a pen manager. Three misdemeanor counts – illegal movement of a non-ambulatory animal – were filed against an employee who worked under that manager. Both were fired.

Authorities said the video showed workers kicking, shocking and otherwise abusing "downer" animals that were apparently too sick or injured to walk into the slaughterhouse. Some animals had water forced down their throats, San Bernardino County prosecutor Michael Ramos said.

No charges have been filed against Westland, but an investigation by federal authorities continues.

About 150 school districts around the nation have stopped using ground beef from Hallmark Meat Packing Co., which is associated with Westland. Two fast-food chains, Jack-In-the-Box and In-N-Out, said they would not use beef from Westland/Hallmark.

Most of the beef was sent to distribution centers in bulk packages. The USDA said it will work with distributors to determine how much meat remains.

Federal regulations call for keeping downed cattle out of the food supply because they may pose a higher risk of contamination from E. coli, salmonella or mad cow disease, since they typically wallow in feces and their immune systems are often weak.

Upon learning about the recall, some legislators criticized the USDA, saying the federal agency should conduct more thorough inspections to ensure tainted beef doesn't get to the public.

"Today marks the largest beef recall in U.S. history, and it involves the national school lunch program and other federal food and nutrition programs," said U.S. Sen. Tom Harkin, chairman of the Senate Committee on Agriculture, Nutrition and Forestry. "This begs the question: How much longer will we continue to test our luck with weak enforcement of federal food safety regulations?"

Advocacy groups also weighed in, noting the problems at Westland wouldn't have been revealed had it not been for animal right activists.

"On the one hand, I'm glad that the recall is taking place. On the other, it's somewhat disturbing, given that obviously much of this food has already been eaten," said Jean Halloran, director of food policy initiatives at Consumers Union. "It's really closing the barn door after the cows left."