Veterinarians question use of ventilation shutdown

AVMA draws scorn over its qualified endorsement of method for depopulation

Published: June 30, 2020
By Jennifer Fiala

Screenshot of Facebook live event
Members of the animal rights group Direct Action Everywhere spent several days this month protesting in front of the home of Dr. Janet Donlin, CEO of the American Veterinary Medical Association. The group objects to AVMA guidance that includes the use of ventilation shutdown plus heat to cull animals in some circumstances.

The American Veterinary Medical Association has become a target of public and professional outrage over its inclusion of ventilation shutdown, or VSD, along with heat, as a means for mass-exterminating animals during times of crisis.

The controversy has played out on live Facebook posts, media reports and online forums, and spotlights moral and philosophical divides within the profession on when to cull animals and how to do so humanely. The issues are so contentious, some practitioners fear they can't express their opinions about depopulation — even to colleagues — without drawing retaliation, sometimes in the form of public shaming. 

The urgent need to depopulate livestock is a consequence of the COVID-19 pandemic. The United Food and Commercial Workers International Union reports that more than 14,000 meatpacking workers have been sickened by or exposed to the novel coronavirus, causing plants across the country to temporarily close or run below normal operating capacity. COVID-19-related disruptions have caused a backlog of about 600,000 hogs intended for slaughter in Iowa, creating capacity issues and tough choices for farmers forced to thin their herds, state authorities say. 

"Pork producers are going to extraordinary lengths to find solutions, but it's not enough to make up for the backlog happening on farms. Euthanasia is a very difficult decision for producers to make and is always used as a last resort," Iowa Secretary of Agriculture Mike Naig said in a news release.

Federal and state agriculture agencies accept the use of VSD for depopulation in crisis situations, as does AVMA guidance, which states that using VSD to depopulate animals should be as "a last resort" that "must only be considered when all other options have been thoughtfully considered and ruled out." 

In late April, undercover activists surreptitiously recorded the use of VSD, which involved closing doors, turning off fans and pumping hot air into a facility housing hundreds pigs at Iowa Select Farms, the state's largest pork producer. The activists, responding to a tip from a farm employee, filmed as rising temperatures caused the animals to die from hyperthermia. With the recordings circulating the internet, the topic of using VSD to cull pigs — as opposed to other techniques, such as captive bolt or gunshot — has raised polarizing debate among veterinarians. 

Unveiled last week, the website Veterinarians Against Ventilation Shutdown prompts practitioners to petition the AVMA to reclassify VSD as a means for depopulating animals. Other veterinarians recently called for change in a letter to the AVMA. "If the public discovers the AVMA approved and condones Iowa Select Farm's use of ventilation shutdown, it will severely damage the reputation of the profession as caring advocates for animals," the letter states. 

In a statement to the VIN News Service, the AVMA said it was not involved in the Iowa Select Farms incident: "The AVMA has insufficient information about the situation at the Iowa facility to determine whether all feasible alternatives to depopulation were explored prior to the facility making the decision to depopulate pigs using VSD during COVID-19."

Raising public awareness about livestock conditions is an objective of the animal rights group Direct Action Everywhere, which uses internet campaigns and shock tactics, such as burying pig carcasses on the property of Iowa Select Farms CEO Jeff Hansen, to drive a message that using VSD to kill pigs is unacceptable. Direct Action Everywhere investigator Matt Johnson and others have protested at AVMA headquarters in Schaumburg, Illinois. During a visit on June 15, activists entered the near-empty building and played from a speaker the sounds dying pigs. "This is the organization which has basically given the industry free rein … to practice this ventilation shutdown. This [is a] barbaric practice, where pigs are literally roasted alive," Johnson shouted in the AVMA lobby

Protesters also demonstrated at the home of AVMA CEO Dr. Janet Donlin, carrying signs reading "AVMA stop roasting pigs alive" and showing an image of Donlin flanked by dollar signs. Police eventually dispersed the activists.

Residential picketing is a "pressure tactic," said Johnson, who grew up on an Iowa dairy farm and says he's familiar with the plight of producers. "If there was another way to accomplish our goals, we'd be all for that," he said in an interview. "There has been no dialogue [with the AVMA] whatsoever."

Asked what he'd consider to be a more acceptable way to cull livestock, Johnson did not offer concrete suggestions but refused to accept that VSD was the most logical, humane way to depopulate pigs. "I think we can figure out a better way to do this," he said.

Depopulation methods outlined

While no single agency in the United States specifically governs the euthanasia or depopulation of animals, a patchwork of federal, state and local regulations include directives for animal welfare, carcass disposal and the humane slaughter of animals. 

The USDA APHIS approves of using VSD, largely as a means for culling diseased animals, when necessary. However, the agency lists gunshot, electric shock, captive bolt and carbon dioxide as the preferred means for depopulating pigs, depending on "field conditions," and cites the AVMA as a source for federal policymaking in this realm.

While the AVMA is not a regulatory body and has no authority over depopulation decisions made by producers or state and federal agencies, the influential organization has long studied how and when to kill mass numbers of animals in times of crisis. For decades, such guidance had accompanied the AVMA Guidelines on Euthanasia, which has been around since 1963. The AVMA issued its first-ever Guidelines for the Depopulation of Animals in April 2019, and an accompanying flowchart for evaluating options for depopulating animals during emergencies. 

Dr. Jan Shearer, the dairy extension veterinarian at Iowa State University and then-chair of the AVMA Panel on Euthanasia, explained at the time that depopulation needed "comprehensive" attention. "I think these guidelines are critically important in the sense that it's what everyone leans on during times of crisis," he said. 

The document was part of a two-year endeavor by the AVMA Panel on Depopulation, which convened more than 60 experts who reviewed some 250 comments for the publication. "All of the AVMA's humane endings documents, including its euthanasia, humane slaughter and depopulation guidelines, are continuously reviewed and updated as new information becomes available," according to a statement the AVMA provided last week to VIN News.

The statement said the AVMA was not consulted by Iowa Select Farms: "We were not involved in their decision to depopulate, we were not consulted as to what method might be most appropriate for their situation, and we were not asked for input on or oversight of the method's implementation."

The statement continued, "... [Q]uestions about why the facility/company decided to depopulate, why they chose VSD as the method to do so, and what happened during the implementation of VSD at the facility are best directed to those responsible for that facility's operations."

Iowa Select Farms Communications Director Jen Sorenson did not return phone calls from VIN News.

Rapid mass culling of animals most often is done to contain infectious diseases. Earlier this month, authorities in the Netherlands gassed tens of thousands of mink raised for fur on Dutch farms, owing to public health concerns that the animals were susceptible to SARS-CoV-2 and could cause new outbreaks in humans.

A more controversial depopulation case occurred in February 2003, when Dr. Gregg Cutler, a prominent poultry veterinarian and epidemiologist in greater Los Angeles, came under fire for authorizing the use of an industrial tree shredder to kill 30,000 hens from egg ranches in Escondido, California, and elsewhere in San Diego County. Cutler, who at the time was a member of the AVMA Animal Welfare Committee, told authorities with the local sheriff's department that "a large chipper can be rented and set up to discharge directly into a loader bucket or other container. Death is instant and humane."

The AVMA, which came under fire for not revoking Cutler's membership, responded with a statement in May 2003 titled "Wood chippers not to be used to euthanize poultry."

"It is absolutely absurd and ludicrous to believe that any veterinary medical association, especially an association that has for more than 140 years been the leading voice for humane and proper care of animals, could or would advocate throwing live chickens into a wood chipper as an appropriate method of euthanasia," said Dr. Bruce Little, who at the time was the AVMA CEO and executive vice president.

Debating reclassification

Dr. Crystal Heath, a practitioner in Berkeley, California, wants the AVMA to be similarly indignant about VSD. "I believe the majority of AVMA members do not approve of VSD except as a 'last resort' depopulation method and AVMA intended VSD to be used only in extreme conditions of infectious or zoonotic disease outbreaks or natural disasters," she said by email. "AVMA approval has allowed pig and poultry producers to use VSD as a cost-savings procedure to cheaply destroy unprofitable or excess animals."

If VSD were reclassified as "not recommended" in the AVMA depopulation guidelines, federal and state regulatory agencies might be less likely to permit its use, Heath said. She pointed out that the American Association of Swine Veterinarians prefers other depopulation methods ahead of VSD, as outlined in its Recommendations for the Depopulation of Swine, updated last month. 

VSD should be permitted only under "constrained circumstances" and used in combination with additional heat sources or carbon dioxide "to achieve the goal of 100% mortality," the AASV document states. Such situations could include "constraints on zoonotic disease response time, human safety, depopulation efficiency, deployable resources, equipment, animal access, disruption of infrastructure, and disease transmission risk."

The AVMA guidelines also uses "constrained circumstances" as a condition that permits the use of VSD and mirrors AASV constraint scenarios. 

Whether economic hardships associated with COVID-19 meet that definition is a matter of opinion. AASV Executive Director Dr. Harry Snelson said he can't speak for how the group's 1,700 members feel about the use of VSD but says veterinarians take seriously their responsibilities to promote the health of animals, the public and food safety. COVID-19, he said, has been stressful on farmers and swine veterinarians, and presents a "unique situation" that's forced veterinarians and their clients to make tough decisions. 

"It's one thing if you have to put down sick or diseased animals, but it's another to have to dispose of healthy animals because of conditions out of your control," Snelson said by email. "Swine vets and their clients have done an incredible job finding ways to avoid having to dispose of these animals. They are holding the animals longer than normal in existing facilities, they have altered the diets to slow the growth, they have given animals away, they have sold animals to nontraditional markets, etc.

"But, despite all their efforts," he continued, "at some point the decision has been made to dispose of the animals, and vets and farmers have to determine what methodology is most appropriate for their given situation."

Little consensus

VSD and the pig-culling controversy have spurred heated discussions on message boards the Veterinary Information Network, an online community for the profession and parent of the VIN News Service. In a post that's generated 146 comments to date, Dr. George Bates of Chambersburg, Pennsylvania, invited colleagues to read an article about the findings at Iowa Select Farms by undercover activists. "Death by slow roasting has never before, to my knowledge, been classified as a 'humane death,' " he said. 

Most of the comments that immediately followed echoed Bates' sentiments. Then Dr. Jami Stromberg, who owns a small-animal practice in Brooklyn Park, Minnesota, weighed in, noting that while "the entire situation sucks," she could share some understanding of what's she's learned about swine production systems.

"These plants are not equipped to handle pigs that weigh more than a certain amount," she said in the discussion. "They would literally break the machinery. Therefore, the pigs coming to market size had no place to go. If they stayed on the farm, the farmers would have to restrict their rations — literally starve them — to keep them from growing. And that doesn't buy a lot of time because the pigs will still grow, and now you have young pigs coming in that need a place. Options included slaughtering them at smaller facilities, but these facilities were already overloaded with demand. You could sell the live pigs to people to slaughter themselves, but how many people want to do that?"

She continued: "... There are not a lot of good ways to kills hundreds or thousands of pigs in a short time. Can you think of a better way? Hold them down one-by-one and inject them? Shoot them in the head? These are 300 plus pound animals. ... Trust me, many companies lost a ton of money by essentially having to bury food, so this was not an economic decision as much as a 'we need to do something now and there aren't a lot of options' decision."

While Stromberg's comment drew a slew of counter responses, some on VIN agreed with her. At least one mixed animal practitioner sympathetic to the plight of pandemic-impacted producers expressed a hesitance to enter the discussion and declined to talk with VIN News, wary of public attack. 

Dr. Joe Waldman, of Alberta, Canada, countered the call to petition the AVMA on VSD. "With all due respect, a team of experts came up with strategies for unprecedented situations," he said in the discussion. "Whether or not this rises to that level is worthy of investigation but I am not comfortable condemning the protocol, the organization or the people who were tasked with drafting it."

Dr. Meghan Ellis, owner of a mobile clinic in Sanford, North Carolina, said the situation calls for greater veterinary oversight of food animal production: "I agree that as things stand now there are maybe no alternatives to VSD. But things gotta be done right, and we have to be present to make sure it is done right. ... Moving forward, the system must change and veterinarians must be involved," she said. 

Editor's note: The headline was changed from the original, post-publication.

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