In the realm of animal protection, the chickens that we eat, known as broilers, have been the proverbial elephant in the room.

Their numbers are almost inconceivably vast. Roughly 9 billion chickens are slaughtered every year in the United States, making up well over 90 percent of the land animals killed for food .

Yet broiler chickens have mostly not benefited from a wave of improvements to farm animal welfare policies announced in recent years by large meat producers and food chains.

On Thursday, that changed. Within an hour of each other, two of the worlds largest food services companies, Compass Group USA and Aramark , announced sweeping new welfare improvements for broiler chickens in their supply chains.

Both companies manage dining operations at thousands of hospitals, universities and other large institutions. Together, their new policies will improve the wellbeing of over 100 million animals every year.

Im not aware of another day in U.S. history that produced policies that affected more animals than the ones announced today, said Josh Balk, food policy director at the Humane Society of the United States. If there is one, Im not aware of it. I cant think of one that comes close.