When animal-shelter employee Rosemary Ficken opened the door to the St. Louis pound's gas chamber one August day in 2003, she couldn't believe her eyes: A reddish brown mutt, standing on top of six dead dogs, was still alive.

In the shelter's 64 year history, no dog had ever survived the chamber's noxious fumes.

Unwilling to close the door and re-gas the dog, Ficken called Randy Grim, the founder of Stray Rescue of St. Louis. The Missouri organization rescues abused and neglected animals, restores them to health, and places them in new homes.

Grim retrieved the big-eared Basenji mix and named him Quentin after California's San Quentin prison.

Quentin's life was spared that day, but many others are not so lucky. Nearly four million dogs and cats in the United States are put to death in shelters each year.

Carbon monoxide gas chambers—a euthanasia method used since World War II—are routinely used in animal shelters throughout the country, including Rhode Island, Ohio, Texas, and Virginia.

The American Veterinary Medical Association—whose euthanasia guidelines are widely followed—considers carbon monoxide gassing an acceptable method when done in a properly manufactured and equipped chamber. Many animal-welfare advocates, though, say the method is inhumane.

"It's America's dirty little secret," said Grim, who has written the book Miracle Dog: How Quentin Survived the Gas Chamber to Speak for Animals on Death Row （Alpine Publishing）. "If people actually saw the gas chamber working, they would sign a petition tomorrow to ban it." Due to Grim's fundraising and lobbying efforts, the St. Louis gas chamber shut down in January of this year.

From start to finish, the process of gassing an animal takes about 25 minutes. One or more animals are placed in an airtight chamber, and a high concentration of bottled carbon monoxide gas is released. Cats and dogs are rendered unconscious within a minute, then eventually die from lack of oxygen.

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."

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 states—Colorado, Georgia, Indiana, and Nebraska—require 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.

毒气或注射 动物安乐死引争论

那是2003年8月份的一天，当美国一家动物保护组织的工作人员罗斯玛丽·菲肯打开动物毒气室的大门时，她被眼前的一幕惊呆了。她简直不能相信自己的眼睛，因为在这个动物收容所长达64年的历史中，没有一只被送到毒气室来的小狗还能生还！而她眼前这只其貌不扬的红褐色小狗却做到了，这只小狗站在其它6只已经断气的狗身上，它依然活着。

看到眼前这一幕，菲肯不愿意再把毒气室的门关上，让这只侥幸生还的小狗再次置身于可以致命的毒气室中了。就这样，小狗得救了，它奇迹般地捡回了一条命。

据报道，菲肯是美国圣路易斯迷路动物收容所的创立者，这个动物收容所是位于美国密苏里州的一家非营利性动物营救组织，它主要对那些被人们虐待或是被主人忽视的小动物实行救援，帮助它们恢复健康，并给它们寻找新主人，安置新家。

动物福利的倡导者兰迪·格里姆成了这只小狗的新主人，而且他还以美国加州著名的圣-昆廷监狱的名字给这只大难不死的小狗取名为昆廷。昆廷是一只长着大耳朵的混合着巴辛吉犬血统的小狗，是个名副其实的幸运儿。但是和它比起来，其它一些小狗则远没有昆廷那么幸运。有数据显示，美国每年将近有400万只生活在动物收容所中的小猫小狗要被杀死。

一氧化碳毒气室——这是自二战以来美国各州的动物收容所（其中包括罗得岛州、俄亥俄州和得克萨斯州等）普遍使用的一种安乐死方法。

尽管美国兽医协会（American Veterinary Medical Association）认为，在一个人造的，装备得很好的小房间中释放一氧化碳气是个可以被接受的安乐死方法。但是，美国许多动物福利提倡者却认为这个方法是不人道的，而且是很残忍的。

“这是个美国的肮脏的小秘密”，昆廷的主人格里姆如此说道，“如果人们真切地看到毒气室运作，他们或许就会签署一份请愿书，要求禁止这项行为了”。格里姆还把昆廷的经历写成一本名为《非凡的小狗：昆廷如何在毒气室中生还并代表死囚区的动物讲话》（Miracle Dog: How Quentin Survived the Gas Chamber to Speak for Animals on Death Row）的新书，另外由于他积极筹款以及不懈地游说相关人员，在他的努力下，圣路易斯毒气室终于在今年1月份被关闭。

从开始到结束，对动物完成毒气安乐死的过程只需要25分钟左右。当一只或几只“被判死刑”的动物被送到一个密封室之后，一个装有高浓度一氧化碳气的瓶子就会不断释放出这种有毒气体。这时，密闭室里的小猫或小狗会在一分钟之内丧失知觉，并且最终会因为缺氧而死亡。

对此，动物安乐死专家道格·法克玛表示，在理论上，毒气室这个方法听起来还不错，但事实上，这个方法是很可怕的。他说：“很多被实施安乐死的动物通常会置身于一个暖箱或者很热的箱子里，它们不知道接下来将要发生什么事情。释放毒气的时候，毒气室内会发出嘶嘶作响的声音，这些动物会觉得眩晕，它们会惊慌失措，会发生彼此间的撕咬，有时人们还能听见它们痛苦的叫声。”

现在，美国大部分私人及城市的动物收容所采用静脉注射巴比妥钠盐的方法对动物实施安乐死。专家表示，这种方法能在几秒钟内使动物没有痛苦地死去。一些私人经营的动物医院也对一些患有重病或者年老力衰的家养宠物实施静脉注射安乐死。

对此，美国人道协会（American Humane Association，AHA）表示，这种静脉注射的方法是惟一一种能够被接受的，可用于狗和猫的安乐死方法。据美国人道协会称，现在美国有13个州，其中包括加利福尼亚、佛罗里达和纽约等，要求动物收容机构以静脉注射的方法对一些动物实施安乐死。

而在美国犹他州伊诺克的乡下村舍里，动物收容机构使用的是古老的小型敞蓬卡车排放出的一氧化碳气，对动物实施安乐死。2002年，动物福利组织对其做法进行了严厉的批评。为了平息外界的争论，该地的动物收容所还专门雇佣了一名兽医，对一只死于毒气室的体重为50磅（约为23公斤）的狗进行了尸检。兽医的验尸报告显示，在这只狗的呼吸道内没有热伤的证据，另外也没有在狗的嘴部和足部发现损伤，这表明当时这只狗并没有做无谓的反抗，或试图逃脱。

伊诺克的动物管理官员吉姆·米切尔表示，因为这个动物收容所一个新扩建的房间阻碍了敞蓬卡车与毒气室的联接，所以该毒气室将很快使用瓶装的一氧化碳气对动物实施安乐死。但米切尔同时表示，这个动物收容所将不会改用静脉注射的方法，他说：“我认为注射式的安乐死其实是很不人道的，除非现场有一名兽医能对注射安乐死的过程进行监督和执导。”

另外，他还指出，如果对一只狗进行胸腔注射时，过量使用巴比妥酸盐可能会使药剂生效的过程长达20至30分钟，而在这段时间里，这只狗会感觉不舒服，并且很可能会发生抽搐和痉挛的现象。

据美国兽医协会2000年公布的安乐死报告显示，事实上，在动物的肌肉或胸腔内注射巴比妥钠盐也并不是一个非常好的方法。而且，一些具有攻击性的动物还要在注射安乐死药剂之前，先注射镇静剂。

美国人道协会的动物保护工作负责人朱迪·巴克曼表示，对各个动物收容所的工作人员进行正确实施安乐死的技术培训是非常重要的。她说：“我们希望这些工作人员是最最仁慈的，因为他们照顾着这些无人问津的无家可归的动物们。”

现在，美国已经有4个州——科罗拉多州、佐治亚州、印地安纳州和内布拉斯加州要求对给动物实施注射安乐死的工作人员进行特殊的技能培训。

在最近几年中，美国各个动物收容所里被实施安乐死的动物数量也呈下降趋势，专家把其中很大一部分原因归结为动物收容所和其它一些慈善团体发起的对动物进行绝育的计划。另外在美国的一些地区，愿意收养动物人也在增多。一些动物保护计划的志愿者还专程开车到动物数量多的地区，把小猫小狗带回来，然后再送到想收养这些动物的其它城市的居民手中。

对此，有关专家表示，或许10年之内，只有那些患病的动物或者是特别危险不适合收养的动物才会被实施安乐死。