A federal judge in Fresno has ruled that pigs too weak or stressed to stand up can still be butchered despite a state law to the contrary, reports Los Angeles Daily News.

US District Judge, Lawrence J. O'Neill, ruled that a 102-year-old federal food safety law that allows swine too sick to stand to be slaughtered under certain conditions supersedes the California law.

Four groups that work for the humane treatment of animals criticized the ruling on 20 February, saying it endangers the nation's food supply. They vowed to appeal.

"This challenge to California law is a stunning example of the meat industry's utter disregard for animal suffering and public safety," said Bradley Miller, national director of the Humane Farming Association, in a written statement.

Representatives of Miller's group, along with The Humane Society of the United States, Farm Sanctuary and the Animal Legal Defense Fund, said the ruling creates a loophole that could lead to the butchering of sick and injured animals.

The state law banning the slaughter of so-called downer animals was written last year in response to an animal rights group's taping of abuse at a Southern California slaughterhouse. Two meat industry groups sued, arguing that the statute would cause good pork to go to waste, concludes the report in Los Angeles Daily News.