The campaign to force America's farmers to change the way they handle their animals celebrated a victory this week.
McDonald's USA announced that in the near future, it will no longer buy eggs from chickens that live in cages.
Those cages are still the industry standard, and 90 percent of America's eggs come from chickens that live in them.
When egg farmers adopted them, decades ago, they thought it was progress. Chicken manure didn't pile up on the floor anymore. Chickens weren't walking around in it. "The eggs were super clean. The feed, the water, everything in these houses became super clean," says Chad Gregory, president of the United Egg Producers, the main industry association.
But animal welfare advocates have been fighting the cages, with some notable successes.
California now demands that all egg-laying chickens at least have enough room to stretch their wings and turn around.
It's possible to meet that requirement with "enriched colony cages" that give chickens more room and nests to lay their eggs. In fact, Gregory says that's the most popular alternative to traditional cages among farmers.
"They would all say that enriched colony cages are the best for the environment, for the cost, for animal welfare, for food safety," he says. This is backed by some industry-funded research.
Consumers, however, find the "cage-free" label more attractive. As the name indicates, cage-free eggs come from chickens that are allowed to roam freely around the chicken house.
This week, McDonald's joined the movement. The maker of Egg McMuffins announced that within 10 years, all of its American and Canadian egg suppliers will be cage-free. And it may need more of those Egg McMuffins: The company recently announced plans to serve breakfast all day long.
Chad Gregory says that farmers who've made the switch are making a pleasant discovery. "They're finding out that those cage-free systems aren't as scary as they once feared," he says.
New cage-free structures allow manure to be removed more easily than in old-style houses, for one thing.
So farmers are hedging their bets, building both enriched cages and cage-free houses.
Old-style cages, meanwhile, appear to be on their way out, although they may not disappear completely for many years.
RENEE MONTAGNE, HOST:
We can say this definitively about selling eggs. Consumers prefer cage-free eggs, which is why McDonald's USA says it will gradually move away from the other kind. NPR's Dan Charles reports.
DAN CHARLES, BYLINE: When egg farmers moved their chickens into small cages made of metal wire decades ago, they thought it was progress. Chad Gregory, president of United Egg Producers, says chicken manure didn't pile up on the floor anymore. Chickens weren't walking around in it.
CHAD GREGORY: The eggs are super clean. The birds remain super clean. And the feed, the water, everything in these houses all of a sudden became super, super clean.
CHARLES: Cages became the industry standard. Ninety percent of the country's egg-laying chickens still live in them. But animal welfare advocates have been fighting these cages with some notable successes. California now demands that all egg-laying chickens at least have enough room to stretch their wings and turn around. Farmers can go cage-free. That's where chickens can roam around freely inside a building. Or they can build so-called enriched colony cages that give chickens more room, also nests to lay their eggs. Gregory says that's the one that farmers would prefer.
GREGORY: They would all say enriched colony cages are the best for the environment, for the cost, for animal welfare, for food safety.
CHARLES: But cage-free is easier to sell to consumers?
GREGORY: Yes, yeah.
CHARLES: A growing number of big egg buyers are now demanding cage-free eggs, General Mills, Nestle - and this week, a really big egg customer - McDonald's USA and Canada. Chad Gregory says even farmers are coming around to the idea.
GREGORY: They're finding out those systems - cage-free systems - aren't as scary as they once feared they would be.
CHARLES: There are new ways to remove the manure and collect the eggs. So big egg producers are now hedging their bets, building both enriched cages and cage-free houses. The old-style cages, though, they're on their way out, gradually. Dan Charles, NPR News. Transcript provided by NPR, Copyright NPR.