The largest beef recall in US history – more than 140 million pounds of it – was sparked by a covert Humane Society video showing employees at the Westland/Hallmark Meat Co. in Chino, Calif., dragging so-called "downer" cows onto a killing floor. Federal officials determined the cows had not been properly inspected. Although no illnesses were tied to the recall, it sparked changes in food-safety procedures, caused the company to close, and led to the criminal conviction of two employees.
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