Raj A B, Whittington P E
Department of Clinical Veterinary Science, University of Bristol, Langford.
Vet Rec. 1995 Mar 25;136(12):292-4. doi: 10.1136/vr.136.12.292.
The efficacy for the euthanasia of day-old chicks of mixtures of carbon dioxide and air, or carbon dioxide and argon containing 1, 2 or 5 per cent residual oxygen, or argon containing 1 or 2 per cent residual oxygen was tested in three experiments. The time to the onset of unconsciousness of individual chicks, determined from the time to loss of posture, was similar during their exposure to 2 per cent oxygen in argon, 20, 30 or 40 per cent carbon dioxide in argon with 2 per cent residual oxygen, or 90 per cent carbon dioxide in air. The exposure of chicks in batches of 20 to a mixture of 20, 30 or 40 per cent carbon dioxide in argon resulted in the death of all the chicks within two minutes. However, a residual oxygen level of 5 per cent in these mixtures resulted in the survival of some chicks for longer than two minutes. With argon alone the level of residual oxygen was critical; less than 2 per cent was essential to achieve 100 per cent mortality within three minutes, and a rise from 2 to about 3 per cent resulted in up to 20 per cent of the chicks surviving for seven minutes.
在三个实验中测试了含有1%、2%或5%残余氧气的二氧化碳与空气的混合物，或二氧化碳与氩气的混合物，以及含有1%或2%残余氧气的氩气对一日龄雏鸡实施安乐死的效果。根据雏鸡失去姿势的时间确定，个体雏鸡在暴露于含2%氧气的氩气、含2%残余氧气的20%、30%或40%二氧化碳与氩气的混合物，或空气中90%二氧化碳的过程中，开始失去意识的时间相似。将20只一批的雏鸡暴露于含20%、30%或40%二氧化碳的氩气混合物中，所有雏鸡在两分钟内死亡。然而，这些混合物中5%的残余氧气水平导致一些雏鸡存活时间超过两分钟。单独使用氩气时，残余氧气水平至关重要；低于2%对于在三分钟内实现100%死亡率至关重要，而从2%上升到约3%会导致高达20%的雏鸡存活七分钟。
