An undercover video showed workers using forklifts to get sick cows to the slaughterhouse. It's that video that caused the largest beef recall in United States' history. The 143-million pounds of meat was mainly used in school cafeterias and fast food restaurants.

As disturbing as the video is, what may be more disturbing is that the animals, too sick to walk, could have ended up in the food chain.

The undercover footage was shot by the humane society, and it has lead to the largest recall of meat in United States history. The USDA has ordered more than 140 million pounds of fresh and frozen beef off store shelves. The meat was processed by the Westland/Hallmark Meat company in Chino, Calif. The Humane Society claims, this video shows cows being shocked and even pushed with a forklift to get them to walk into the slaughterhouse, so they can pass inspection. When animals are too sick too walk, it's against the law to use them for human food.

Westland/Hallmark Meat is a supplier beef to two major West Coast fast food restaurants, and the company is a major supplier for the federal school lunch program. The USDA released a statement that said in part: "We don't know how much product is out there right now, we don't think there's a health hazard, but we do have to take this action." Critics said the Feds dropped the ball.

"It's clear the USDA system failed and it allowed this company to engage in long term inhumane practices," said Paul Shapiro.

The recall covers every beef product Westland/Hallmark Meat has produced in the last two years. No charges have been brought against the company for safety issues, but two employees have been charged with animal cruelty.