Minnesota's $2.5 billion hog industry is on the defensive, with farmers under growing pressure to change how they raise pigs.
At issue is the widespread practice of housing pregnant sows in stalls so small the animal can't turn around. The hog stall used by most farmers is roughly seven feet long by two feet wide — about the same size as a pregnant sow weighing 600 pounds or more.
Inside the stall, there is room for the animal to back up a bit, but not turn around. That keeps the sow from contaminating her food and water with her own waste.
Although most farmers say the hog stall is an efficient production tool, the stalls have been the target of a long-running campaign alleging they impose a lifetime of misery on the pigs. But according to new research paid for in part by pork producers, the stalls may well be better for the animals than letting them roam free.
That isn't likely to convince opponents of the practice, however.
"Sow gestation stalls are something that's just not going to be possible to sell to the public," said Temple Grandin, a world-renowned animal science professor at Colorado State University.
Grandin has compared the stalls to living in an airline seat. A consultant for many large meat companies including Minnesota-based Hormel, she uses her frequent airplane trips to gauge public opinion by showing seatmates pictures of the stalls.
A typical reaction came from someone who had hunting dogs.
"He said 'I wouldn't put my hunting dogs in that,' " Grandin recalled. "And the thing that bothered him was the fact that they couldn't turn around for most of their life."
Some corporations are putting intense pressure on farmers to abandon stalls. Hormel, McDonalds, Safeway and Smithfield Foods all say they'll either stop using stalls, or stop buying pork from stall farms. At least eight states have also passed legislation restricting or phasing out the stalls. But many people approve of the use of stalls. Firmly in that group, are most of the nation's hog farmers.
Southwest Minnesota hog producer Randy Spronk has watched the criticism of hog stalls grow from a few scattered voices to a concentrated campaign. In his current position as president of the National Pork Producers Council, the country's largest hog group, he's right in the middle of the debate.
"The way it's being portrayed I think is going to mislead society and be detrimental to society in the long run," said Spronk, a third-generation livestock farmer.
Eliminating confinement pens would raise the cost of pork for the consumer, he said. Farmers would have to renovate their barns into stall free facilities, driving up the cost of production.
That also might be problematic for farmers, Spronk said, because when sows are housed together in open pens, they fight.
"There are sows that become very aggressive in biting," he said. "And can cause lacerations, can cause bleeding and actually can cause lameness in some other sows. They can be very vicious."
There are studies supporting both sides in the debate. But peer-reviewed University of Minnesota research, paid for in part by the pork producers council, suggests sows in crates experience less stress than those in open pens.
At the University of Minnesota's swine research facility in Waseca, long rows of hog stalls line one of the main barns on campus. Nearby are sows in open pens.
For 11 years, Animal Science Associate Professor Sam Baidoo has compared the two groups. To gauge stress levels, Baidoo measured a hormone called cortisol, a stress indicator. Baidoo found that cortisol levels of sows in open pens are more than 75 percent higher than those of sows confined in stalls. He said that could help explain why sows in stalls typically produce more baby pigs, Baidoo said.
"Those in stalls performed better than those in the group," he said.
But stall opponents don't buy it. They say producers could breed hogs that are less aggressive, to reduce fights.
Matthew Prescott, corporate outreach director for The Humane Society of the United States' factory farming campaign, said the bottom line is that consumers will not stand to see hogs living in those small stalls.
"Preventing an animal from even turning around, that's just not common sense and it's not good welfare," Prescott said.
Farmers are counting on the consumers to support them at the meat counter. They say they'll be fine if consumers continue to buy stall-produced pork.