Pig housing law exposes a divided veterinary profession

U.S. Supreme Court mulls constitutionality of California standard

November 4, 2022 (published)
YouTube screenshot
A 2013 video by Pork Checkoff credits sow gestation crates for providing pigs with individualized access to food, water and protection from aggressive animals while offering socialization between stall neighbors. Much of the public, however, considers such tight confinement to be cruel.

A case being decided by the U.S. Supreme Court that could affect millions of pigs highlights disagreement between segments of the veterinary profession over animal welfare and agriculture practices, ethics and ideology.

National Pork Producers Council et al. v. Karen Ross et al. challenges the constitutionality of California's Proposition 12, also known as the Farm Animal Confinement Initiative. (Ross is the state food and agriculture secretary.) The law, which was passed by voters in 2018 and went into effect this year, sets minimum housing sizes for pregnant sows, veal calves and laying hens raised in California, and bans the sale of pork, veal and eggs from out-of-state suppliers that don't meet the housing standards.

The case implications reach beyond animal welfare. The suit raises fundamental questions about states' rights versus the power of individual states to direct the activities of other states, especially when it comes to commerce.

It also has pitted veterinarian against veterinarian, with some coming out in support of the law and others against it.

An amicus brief signed by 378 veterinarians and animal welfare scientists argued to the court that gestation crates cause pigs "needless suffering" and cited supporting research. "Some examples of suffering are physical, such as injuries from crate bars and urinary tract infections that afflict pigs forced to stand, sit, and lie down day after day in their own excrement," the brief says. "Other examples of suffering are psychological."

Arguing for the pork producers, the American Association of Swine Veterinarians submitted an amicus brief maintaining that there's inadequate scientific proof that small enclosures harm animals or that other housing methods are significantly better. In fact, they argue, existing housing systems protect livestock from physical harm by other animals. "Unfortunately, in many respects, the stall issue has been driven primarily by perception ... " the brief reads. "[T]here is strong scientific consensus that individual stalls provide health benefits by protecting sows from aggression and social subordination."

Officials with AASV, which represents approximately 1,300 veterinarians, did not respond to VIN News Service requests to elaborate. Several large animal practitioners in favor of current swine housing practices declined to talk publicly to VIN News, citing concerns that animal activists might retaliate.

In brief

Justices, who heard oral arguments on Oct. 11, recognized the veterinary factions. "We're going to have to balance your veterinary experts against California's veterinary experts, the economic interests of Iowa farmers against California's moral concerns and their views about complicity in animal cruelty," Justice Neil Gorsuch told a lawyer representing pork producers. "Is that any job for a court of law?"

Background on Prop. 12

Under Prop. 12, businesses are barred from selling meat and eggs in California derived from animals confined in a "cruel manner." The law, which took effect in January, requires giving breeding pigs each 24 square feet of space; veal calves 43 square feet; and egg-laying hens 144 square inches. 

The case before the Supreme Court focuses on California's swine housing stipulations and their impact on out-of-state producers. Prop. 12 restricts the importation and sale of meat that was not raised following the state housing rules. With the vast majority of swine operations located outside of California, farmers who use gestation crates say that because they don't know what pork they produce will end up in the state, they would have to alter their housing universally. 

A review by the American Veterinary Medical Association found that a typical gestation crate is 6.5 feet long by 2.5 feet wide — around 14 square feet per sow — to allow sows to lie on their side without their udders protruding from the stall, but dimensions vary. Farrowing crates also provide 14 square feet of space, while gestation pens often are a bit larger, allowing at least 20 square feet per individual and the ability to move freely. 

According to producers, implementing alternative housing such as larger crates or pen systems presents a costly change that result in the loss of farm jobs and raise food prices. Moving away from individual confinement, they say, trades one set of welfare concerns for another: Animals housed in open systems are more vulnerable to disease, parasite infestation and injury due to aggressive pen-mates. 

AVMA to reconsider confinement

Prop. 12 does not call for pen systems, but larger individual crates. Even so, there are advantages and disadvantages to every livestock housing system, the AVMA says. In its policy on pregnant sow housing, the AVMA encourages veterinarians to weigh the risks and benefits of housing systems in accordance with science and their professional judgment.

"For example," the policy reads, "while gestation stall systems minimize aggression and injury, reduce competition, and allow individual feeding and nutritional management, they restrict normal behavioral expression. Group housing systems are less restrictive, but could lead to increased lameness and undesirable social behaviors, such as aggression and competition for resources (e.g., feed, water, space to lie down)." 

For nearly two decades, activist groups such as the People for the Ethical Treatment of Animals and the Humane Society of the United States have pressured the AVMA, which counts some 100,000 veterinarians as members, to oppose gestation stalls and crates. In 2005, the organization responded by vowing to "support sow gestation stalls until a more welfare-friendly housing system that's reliable, efficient and economically viable is conceived."

"Some veterinarians are opposed in principle to close confinement of animals, some are opposed in principle to the use of animals for food, and some work with the swine industry to maintain animal health and productivity," the AVMA noted.

The organization is slated to reassess its stance on pregnant sow housing in 2024, per its regular five-year review cycle. In its existing policy, the AVMA "encourages ongoing research to better understand and meet the welfare needs of gestating sows."

Science might not be enough to decide the matter. As Bernard Rollin, the late bioethicist and philosophy professor at Colorado State University told VIN News in an interview in 2008: "Sound science can tell you how to raise pigs in confinement [but] not if you ought to raise pigs in confinement." 

Laws shaping hog housing

Swine welfare policies aren't limited to California. Judging from a map in a report by the U.S. Department of Agriculture Economic Research Service, 10 states have passed welfare regulations during the past two decades that stipulate minimum space requirements for production pigs. Outside of the U.S., countries such as Switzerland, the United Kingdom, Norway and New Zealand have established farm animal housing standards, and the European Union is poised to eliminate cages altogether.

In the U.S., for the most part, the laws are in states with small pork industries. Ohio, with a 3.3% share of the country's hog inventory, will become the largest hog-producing state to ban gestation crates when a plan passed in 2010 to phase them out takes effect in 2026.

"The proportion of the national herd covered by gestation crate bans is currently estimated at 3% based on expected production in 2022," the USDA report says. "Except for Michigan, each state with existing bans on gestation crates has produced, on average, less than 1% of total U.S. pork production (in pounds) since 2018."

Most of the state laws don't affect producers beyond their borders. Apart from California, only Massachusetts bans the sale of pork from out-of-state hogs raised in gestation crates. Massachusetts law was approved by voters in 2016 through a ballot initiative known as Question 3. It was slated to take effect this August, but enactment is on hold while the Supreme Court considers the reach of Prop. 12. 

The Supreme Court ruling in the California case is expected by next summer.

Update: In a 5-4 vote, U.S. Supreme Court justices upheld a California law that bans the in-state sale of pork products from out-of-state producers that house breeding pigs in spaces that do not allow them to move around freely. The opinion was published on May 11.

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