If you walk out a back door at the Jefferson City Animal Shelter (JCAS) on Hyde Park Road, you'll see a big furnace for animal cremation and an industrial-sized freezer.
What one may not notice is a smaller, white freezer. It's just like one someone may have in his or her home, but it has an entirely different purpose than preserving foods. It's a gas chamber, used to euthanize wildlife and feral cats.
The Jefferson City Police Department, which oversees JCAS and Animal Control, announced Tuesday that the gas chamber will only be used at the shelter to euthanize wildlife and feral cats when the new interim veterinarian, Dr. Corey McCann, is not readily available for euthanasia by injection. The use of the chamber will only occur at the direction and with the authority of McCann.
The press release also announced that McCann will assume all control over the city's Animal Control Program, which includes JCAS.
The shelter veterinarian position was left vacant by Dr. Amanda Dykstra, who resigned from the shelter June 14 and was released early from her month's notice June 27. Her resignation was due in part to her concern regarding the shelter's use of a gas chamber to kill wildlife and feral cats and regarding disagreements between she and the shelter director.
Missouri statute defines humane killing of animals as "the destruction of an animal accomplished by a method approved by the American Veterinary Medical Association's (AVMA) Panel on Euthanasia."
The AVMA deems euthanasia by a gas chamber legal.
Dr. Keith Branson, a clinical assistant professor and anesthesiologist at the University of Missouri College of Veterinary Medicine, said the three most common forms of animal euthanasia are injection, carbon monoxide poisoning in a gas chamber and carbon dioxide poisoning in a gas chamber.
Euthanasia by injection
"The preferred method of euthanasia for animals that are handleable is by intravenous injection of a euthanasia agent," Branson said. "That's considered the preferred method, but the key is animals that are handleable."
Branson said euthanasia by injection is basically an overdose of anesthetic through an IV.
"The first thing that happens is unconsciousness," he said. "Obviously an animal is not going to feel pain or distress if they're unconscious.
"The anesthetic agents also depress respiration, and at really high doses, they decrease how well the heart pumps blood."
Euthanasia by gases
The second most common form of euthanasia is the use of carbon monoxide, most usually in some sort of gas chamber, Branson said.
"The vast majority of concerns about carbon monoxide are not its suitability as a euthanasia agent, but the fact that it's also rather hazardous to the humans that are employing it as the euthanasia method," Branson said. "It works by blocking the red blood cells' ability to carry oxygen through the body."
He said the method is described as an insidious method of euthanasia, because the animal is not really aware what's going on.
"Carbon monoxide poisoning produces unconsciousness by a lack of oxygen to the brain, because you're limiting the animal's ability to transmit the oxygen from the lungs to the tissues and then that's what produces the unconsciousness and ultimately death," Branson said.
He said injection and carbon monoxide are by far the two most commonly used methods of animal euthanasia. Carbon dioxide gas is the third most commonly used.
"It's usually limited to small containers for wildlife," Branson said.
He said carbon monoxide is flammable, so it's better for Animal Control to be driving around with carbon dioxide, which isn't flammable.
Branson said the AVMA also has guidelines pertaining to mechanisms for gas chambers.
He said he has never heard of an old freezer being used as a gas chamber, which is the case at JCAS.
"There are commercially made carbon monoxide chambers and there are some homemade gas chambers," Branson said. "Most of the time, it's more a small closet, or a purpose built room."
He said the biggest thing regarding chambers is that if multiple animals are put in at once, they must be separated.
"Obviously you don't want to put two animals in there that are going to be aggressive towards each other," Branson said. "Then, you have to have a mechanism for delivering the gas so that the concentration goes up fairly quickly, so that they become unconscious rapidly."
When asked about JCAS's gas chamber, Police Department spokesman Capt. Doug Shoemaker said it's obvious what it is.
"It's a gas chamber," he said. "It's a method of euthanasia approved by the state of Missouri."
But he declined to answer specific questions about how animals are euthanized in the freezer and what chemicals are used.
He said he doesn't know who constructed the chamber or how long it's been used at JCAS, but that it has been there for quite some time.