On 16th May 2023, a coalition of animal protection organisations submitted a rulemaking petition to the US Department of Agriculture to require pig slaughter plants to install cameras inside gondola cages used in CO2 stunning systems. The petitioners are the Animal Welfare Institute, Compassion in World Farming, the Humane Society of the United States, the Humane Society Legislative Fund, the Humane Society Veterinary Medical Association, and World Animal Protection.

An estimated 90% of the 130 million pigs killed in the United States each year are slaughtered using CO2 gas, and recent undercover investigations in the US and Australia have documented extensive suffering during this process, including pigs screaming, gasping, thrashing, and convulsing before collapsing in steel cages. As a result, more than 100 US veterinarians have joined in a letter to the American Veterinary Medical Association, expressing concerns about pigs’ aversive reaction to the gas.

Currently, US government inspectors are unable to determine whether pig slaughter plants using CO2 gas are complying with the federal Humane Methods of Slaughter Act (HMSA). Inexplicably, the use of CO2 gas appears to be the only approved slaughter method that plant inspectors are not able to directly observe.

Zack Strong, senior attorney for the farmed animal program at the Animal Welfare Institute, said, “Since pigs represent the largest percentage of mammals that fall under the HMSA, the USDA is failing to enforce the nation’s sole humane slaughter law for a large majority of the animals killed for food in our country. By granting our petition, the department will be able to determine if it has been missing a significant number of humane slaughter violations by not observing CO2 stunning.”

Gillian Lyons, director of regulatory affairs for the Humane Society Legislative Fund, said, “The USDA is not allowed to take a ‘see no evil’ position regarding the slaughter of pigs; the agency has a duty to ensure each animal is stunned and slaughtered in accordance with the HMSA, and they obviously can’t do that if their inspectors are unable to observe this process.”

Jordi Casamitjana
“Originally from Catalonia, but resident in the UK for several decades, Jordi is a vegan zoologist and author, who has been involved in different aspects of animal protection for many years. In addition to scientific research, he has worked mostly as an undercover investigator, animal welfare consultant, and animal protection campaigner. He has been an ethical vegan since 2002, and in 2020 he secured the legal protection of all ethical vegans in Great Britain from discrimination in a landmark employment tribunal case that was discussed all over the world. He is also the author of the book, ‘Ethical Vegan: a personal and political journey to change the world’.