Burger King, the third-biggest U.S. hamburger chain, has pledged to end the use of the cramped chicken and pig cages targeted by animal welfare activists.
On Wednesday, the Miami-based chain committed to serving 100 percent cage-free eggs in its U.S. restaurants by 2017 and to buy pork only from suppliers with documented plans to end their use of gestation crates for breeding sows.
The announcement comes at a time when U.S. consumers are showing greater interest in agricultural practices after years of remaining largely in the dark about how their food is produced.
At the same time, groups like the Humane Society of the United States and People for the Ethical Treatment of Animals (PETA) have been pulling back the curtain on farm processes and pressuring restaurants and grocery stores to offer food that is produced more humanely.
The Human Society welcomed the announcement from Burger King, which has 7,200 restaurants in the United States, about half as many as fast-food industry leader McDonald's Corp .
McDonald's, the top U.S. hamburger chain by sales, vowed in February to work with its U.S. pork suppliers to phase out the use of gestation crates. Domestic pork producers confine millions of sows in cramped stalls while they raise piglets.
Wendy's Co, which recently edged out Burger King to become the No. 2 hamburger chain in the United States, made a similar announcement in March.
In 2007, following discussions with the Humane Society, Burger King became the first major U.S. restaurant company to begin phasing in cage-free products.
McDonald's and Wendy's have taken steps towards adding cage-free eggs, but neither has announced plans to make the transition completely in the United States.
All of the eggs served in McDonald's European restaurants come from cage-free hens.
Private equity group 3G Capital, which took Burger King private in October 2010, plans to merge it into Justice Holdings , a UK investment firm. When that deal closes in coming months, Burger King will return as a publicly traded company.