Major pork producers Smithfield Foods and Tyson Foods have both announced plans this week to develop animal welfare improvements within their facilities, including moving away from the practice of using sow gestation crates, small metal enclosures that hold pregnant female pigs for most of their adult lives. Gestation crates have come under heavy criticism as inhumane for their use in large-scale animal farming, with the Humane Society of the United States leading efforts to have the practice discontinued. Smithfield’s announcement put in place incentives for contract pork growers to shift to “group housing systems” for pregnant sows before 2022. After that, the company will only renew contracts with growers who have switched to the new system. According to the announcement, the company has already transitioned 54 percent of sows on company-owned farms to the new system. The Humane Society praised Smithfield’s move, saying that it put pressure on other major growers to do the same. “The top producer is telling the world that a transition away from gestation crates is not just an aspiration, but is in the works, is economically viable, and is likely to be achieved in the near term. And we continue to help major food retailers commit to switching their purchasing to crate-free producers,” wrote Humane Society CEO Wayne Pacelle. Tyson, in a letter to its pork suppliers sent Wednesday, said that it was asking all suppliers to improve “quality and quantity of space” for sows in any new or redesigned barns beginning in 2014. “We believe future sow housing should allow sows of all sizes to stand, turn around, lie down and stretch their legs,” Tyson wrote. The language of Tyson’s letter, however, does not mandate any such changes. Tyson’s letter also urged growers to install video surveillance systems to “improve human behavior and animal handling,” alluding to incidences of animal abuse. The letter also discourages the continued use of blunt force to kill sick or injured piglets, referring to the practice of slamming piglets head-first into the ground. “We recognize that this practice has been historically acceptable in the industry but may not match the expectations of today’s customers or consumers,” Tyson wrote. Animal rights group Mercy for Animals said that Tyson’s move was in the right direction, but urged the company to fully mandate its suggestions. “The pork industry’s use of gestation crates is one of the worst forms of institutionalized animal abuse in existence and we praise Tyson for acknowledging that this cruel system must be phased out,” the organization wrote. More than 60 major food companies, including McDonald’s, Burger King, Safeway and Costco have demanded pork suppliers phase out gestation crates. Another major supplier, Cargill, has said it has gotten rid of 50 percent of its crates. Gestation crates are banned in Arizona, California, Florida and Rhode Island, and five other states are requiring growers to phase them out. They are also banned in Sweden, Denmark and the United Kingdom, and will be banned in New Zealand by 2015 and Australia by 2017.