McDonald's USA said that by 2022, it will only buy pork from producers that do not use gestation crates for housing their pregnant sows. Reuters reports that the company will also work with producers and suppliers to develop traceability systems to prove that the meat it buys are not from farms that use such structures.

The company also said that, by 2017, it would seek to source pork for its U.S. business from producers that are also working to phase out such gestation stalls. Animal-rights groups have characterized the use of gestation stalls as being inhumane to the animals.

Everett Forkner, president of the National Pork Board, said the plan would place significant economic pressure on smaller hog operators who don't have access to capital, and may not be able to afford the cost of overhauling barns.

"The additional expenses on farmers forced to make this conversion could increase the risk of them having to leave the business," said Forkner, who also farms in Richards, Mo. "I know on my own farm I moved from open pens to stalls many years ago because too many sows were being injured or denied feed," Forkner said. "When sows are thrown together they can become very aggressive. Dominant sows physically attack the others, bite them and steal their food."

Source: Reuters, Chicago Tribune