A slaughterhouse in the United States has been accused of mistreating cows and forced to recall 143 million pounds of beef, the biggest beef recall yet in U.S. history.
Federal officials say the recall surpasses the 1999 recall of 35 million pounds of beef but they also say no cases of illness related to the recalled meat have been reported.
Investigators for the U.S. Department of Agriculture say the chances of the meat causing illness are remote.
However it has been revealed that some of the cattle were apparently unable to walk after pre-processing inspections and contrary to federal regulations were slaughtered without an inspector examining them for chronic illness, a practice which had been going on for at least two years.
Federal regulations aim to prevent the spread of bovine spongiform encephalopathy, or BSE - the scientific name for "mad cow" disease.
BSE causes a wasting disorder in animals and in humans who consume infected meat and the sickness in cattle has been traced to infected parts from other cattle that were added to the feed of the normally vegetarian cattle.
Experts say 'downed' cattle must be kept out of the food supply because they pose a higher risk of contamination from E. coli or salmonella because the animals tend to wallow in faeces and have weaker immune systems.
The 143 million pounds of meat was from the Hallmark/Westland Meat Packing Company in Chino, California.
Officials say the average age of the cattle involved is 5-7 years, which indicates they were probably born long after a 1997 ban on ruminant feed, and the incidence of BSE in U.S. cattle is "extremely rare."
They say even though the meat does not present a significant health risk it was produced in non-compliance with federal regulations and therefore this action must be taken.
The USDA's Food and Nutrition Service says since October 2006 about 37 million pounds of the meat went to school lunch programs, federal nutrition programs and Indian reservations across the country.
It is believed that most of the meat has probably already been eaten as most of it was a fresh, raw product and would have a very short shelf and refrigerator life.
As most of the beef was sent to distribution centers in bulk packages the USDA expect to be able to determine how much meat remains.