For related articles and more information, please visit OCA’s Factory Farming & Food Safety page and our Breaking The Chains page.

MINNEAPOLIS – Costco Wholesale Corp. on Tuesday joined a growing list of retailers and restaurants in asking suppliers to phase out the use of small pens for pregnant sows, as an animal welfare group prepared to release an undercover video showing conditions at one of its suppliers.

Gestation stalls have been a major target of groups like Mercy for Animals and the Humane Society of the United States. The groups say the stalls are inhumane because they keep sows so tightly confined that they can spend most of their lives and multiple pregnancies with too little space to turn around or even sleep on their sides. Mercy for Animals’ video was shot by one of its investigators in a sow barn at Minnesota-based Christensen Farms, which describes itself as the country’s third-largest pork producer. The group made the video available to The Associated Press before its public release Wednesday. But on Tuesday, Costco gave the group a letter it was sending to pork suppliers urging a phase-out of the crates by 2022. Mercy for Animals’ director of investigations, Matt Rice, supplied the letter to The Associated Press.

Rice commended Costco’s decision. It follows similar decisions by other major food retailers in recent months, including the Safeway and Kroger chains. Rice said his group would turn its attention to the world’s largest retailer, Wal-Mart Stores Inc., which he said also buys pork from Christensen Farms.

A spokeswoman for Bentonville, Ark.-based Wal-Mart, Deisha Galberth Barnett, said the chain offers gestation crate-free Harvestland brand pork products in a number of its stores across the U.S. She said the company will continue to have discussions with its suppliers, groups and food safety experts to find ways to increase that number.

“We believe in offering our customers a choice,” she said.