Whole Foods Market (WFM), which is working with the Global Animal Partnership (GAP), will replace all of its fast-growing chicken breeds with slower-growing breeds. It is reportedly the first major food business to announce the change, planned to be completed by 2024, which the GAP says will support breeds with better genetics and better living conditions.

“The new commitment improves the lives of 277 million chickens, making it the most impactful corporate announcement to date in the U.S. for improving the lives of farm animals,” the group said in an e-mail to Fortune.

The new standards require the following:

• Breeds that are 23% slower growing than conventional chickens.
• Less crowding (stocking density of six pounds/square foot or less, that’s 25% more space that usual).
• Natural light–conventional birds are kept dimly lit. And improvements to straw bales and perches.

The move is part of a broader drive among food manufacturers, retailers and restaurant companies compete with sweeping announcements that proclaim changes to the food they source–promising the new foods and beverages are healthier or more responsible sourced. This is a consumer-driven change, as more Americans say they want better food with an accompanying feel-good message.

Whole Foods was an early mover on the egg front. Since 2004, it made strides to move toward cage-free production. All eggs sold in the company’s stores and all eggs used in Whole Foods’ kitchens and bakeries are now cage-free—and that’s a vow a number of companies have made, though implementation for many will take up to a decade.

All of this comes as Whole Foods faces sales challenges in the competitive grocery space, facing pressure from specialty grocers and even efforts by Target (TGT) and Walmart (WMT) to stock more organic options. Whole Foods’ comparable sales slipped 1.8% for the latest quarter, although sales and earnings beat expectations and the company increased its earnings per share outlook for the year