MINNEAPOLIS (WCCO) – The Humane Society of the United States (HSUS) is accusing a hen processing plant in southern Minnesota of animal cruelty for allegedly drowning conscious hens in scalding hot water and performing other inhumane procedures.

The plant, Butterfield Foods, denies the accusations.

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The HSUS says it conducted an investigation at Butterfield Foods, which is about 45 miles southwest of Mankato, and released graphic video showing birds being slaughtered. The group says this video was the first undercover investigation of a slaughter plant for “spent” hens, a term describing birds no longer commercially viable for laying eggs and sent to slaughter for their meat.

Wayne Pacelle, the president and CEO of The HSUS, wrote about the investigation in The Huffington Post.

“This plant — like nearly all others in the poultry industry — kills birds in an archaic process that would be illegal under federal law if the animals were cattle or pigs,” he wrote.

What the animal advocacy group alleges is that too many Butterfield birds fail to have their throats properly cut by a machine. The hens are then alive when they are dipped in scalding hot water that’s used to help remove their feathers.

The HSUS says its investigation also documented sick birds being thrown against walls or tossed in the trash, overcrowded and sometimes deadly moving conditions, and ineffective/inhumane killing procedures.

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The results of the investigation have been reported to authorities, the HSUS says.

Terence Fruth, an attorney for Butterfield Foods, said that The HSUS’ claims fail the plausibility test.

He said that eight federal inspectors and more than 100 others would have observed the alleged cruelty.

“It is highly unlikely no one would have filed a complaint,” he said.

Fruth added that the company’s latest USDA inspection report was clean.

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In the past, animal advocacy groups have targeted other Minnesota farms. Undercover video taken at Sparboe Farms led to companies like Target and McDonald’s refusing to buy eggs from the producer.