In the controversial world of animal agriculture, large-scale "confinement" operations have often been vilified by animal activists, more-traditional farmers, and even the media. Critics point to small pens, limited sunshine, and fetid manure pits.
But those who work on - or are supplied by - industrial farms say that reputation is undeserved, and many experts in animal welfare admit that the issue is not always black and white.
Which pork chop came from the happier pig? The key, experts say, may be defining "happy" from an animal's point of view - and understanding that farming efficiency and animal welfare are not mutually exclusive.
An advocate of the free-range method, California-based Niman Ranch works with 250 hog farmers in the Midwest. Sold on the East Coast in Whole Foods stores and used in restaurants across the country, its pork comes from pigs raised unconfined and free of antibiotics. Most Niman Ranch farmers, the majority of whom are in Iowa, also raise their own feed.
Frankie Whitman, a company spokeswoman, is critical of more-conventional farms where, she says, "hogs are seen as industrial input." Niman Ranch meat tastes better, says Ms. Whitman, but more important, people can feel good about eating it. Hogs are kept in outdoor huts where they have room to run. They sleep on natural bedding.
"When you talk to a lot of our growers, [you find] this is the same way that they have always grown hogs," she says. "It's not like this is a radical new idea."
Conversely, farmers using high-tech methods aimed at more-efficient production say their animals run less risk of contracting disease from wildlife. Kept in small areas, they are easier to observe and treat, and environmental temperatures can be easily controlled.
"A pig that's freezing to death is probably not happy," says Tom Burkgren, executive director of the American Association of Swine Veterinarians.
Indeed, each approach has its pros and cons, says Don Lay Jr., research leader for the United States Department of Agriculture's Livestock Behavior Research Unit at Purdue University.
What frustrates many industrial farmers, he says, is that the typical consumer has little farm experience and often assumes - without knowing the whole story - that free-range animals automatically have a higher quality of life.
People picture a pig in a pasture and assume "she must be happy," Mr. Lay says. But that pig might have worms from rooting in the dirt, he says. Faced with a Midwestern summer and without the cooling mechanisms found in large barns, it's probably hot.
"It's very important that we don't look at animals as being little people," agrees Edmond Pajor, assistant professor of animal behavior and welfare at Purdue. "What's appealing to you or what you think is important ... is completely irrelevant."
So in a world of tradeoffs, which is the best environment? "I think there's lots of suitable environments," Lay says. And Mr. Pajor says animals need complex environments with room to move.
As researchers try to understand animals' perspectives, Pajor says both traditional and modern livestock producers are striving to find the middle ground between economics and ethics.
"Is that even doable? I don't know," he says. "I think people are trying to do it."