Doug Fakkema, an animal-euthanasia expert, said that, in theory, the gas chamber doesn't sound bad, but in reality it's awful.
"The animal is in a warm or hot box, usually with other animals. They don't know what's going on. The hiss of the gas is going on inside. They get dizzy, and they panic," he said. Fights can break out, and animals' calls can sometimes be heard.
Today most private and city animal shelters euthanize animals with sodium pentobarbital, a controlled substance that is injected into one of a dog or cat's veins. Animals die in seconds, experts say, and without pain or suffering.
Private-practice animal hospitals also use sodium pentobarbital to euthanize sick and old family pets.
The American Humane Association (AHA), an animal- and child-welfare nonprofit, says that lethal injection is the only acceptable method for putting down dogs and cats.
Currently 13 states, including California, Florida, and New York, require animal shelters to perform death by injection, according to the AHA.
In the rural farming community of Enoch, Utah, the animal shelter's brick gas chamber uses carbon monoxide exhaust from an old pickup truck.
The city was heavily criticized for its method by animal welfare organizations in 2002. To put the controversy to rest, the city hired a veterinarian to perform a necropsy on a 50-pound (23-kilogram) dog euthanized in the shelter's gas chamber.
His report found that there was no evidence of heat injury to the dog's respiratory tract. No mouth or foot abrasions were found, indicating the dog did not try to escape.
Enoch's animal-control officer, Jim Mitchell, said the shelter will soon use bottled carbon monoxide gas, because a newly constructed addition to the shelter is blocking the truck's access to the chamber.
The shelter, however, will not switch to sodium pentobarbital, Mitchell said. "Unless you have an actual veterinarian on site to administer and supervise the process, in my mind euthanization by injection is inhumane."
Mitchell explained that only aggressive dogs are put down at the Enoch shelter, adding that the animals would have to be held with a control stick while a lethal injection was administered to their muscle or chest cavity. (A control stick is a metal pole with a wire loop that tightens around an animal's neck.)
He also noted that the massive overdose of barbiturates may take as long as 20 to 30 minutes to take effect if injected into a dog's chest, during which time a dog would be stressed and possibly have convulsions.
Injecting sodium pentobarbital into an animals muscle or chest cavity, however, is not an acceptable practice, according to the American Veterinary Medical Associations Euthanasia Report released in 2000.
Aggressive or fearful animals should be sedated prior to intravenous (within the vein) administration of the drug, the report states.
Proper Training Urged
Jodi Buckman, director of animal-protection services for the American Humane Association, said training shelter workers on proper euthanasia techniques is important.
"We want them to be the most humane people in our communities, because they are taking care of the homeless animals that no one else has taken responsibility for," she said.
Currently four statesColorado, Georgia, Indiana, and Nebraskarequire special training for workers who use lethal injection to euthanize animals.
Animal welfare advocates say euthanasia rates are on the decline. Experts attribute the decline in large part to aggressive spay and neuter programs initiated by shelters and humane societies.
In some parts of the United States, adoptable animals are now even in demand.
To cover the shortfall, volunteers drive to areas where a severe overpopulation still exists, then take dogs and cats to cities seeking adoptable pets.
The retail giant PETsMART recently built a custom bus specifically for this purpose. The Rescue Waggin' program will save more than 4,000 pets annually, the company says.
"Probably within ten years the only animals that will still have to be euthanized are those suffering, health-wise, or [those] that are too dangerous to adopt out," Fakkema, the euthanasia expert, said.
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