Low atmospheric pressure stunning (LAPS) has been suggested for use in poultry under 4 kg in the abattoir as a more humane alternative to carbon dioxide (CO₂). However, there are currently no studies offering a direct comparison of the aversion between methods. Here, we trained adult female broiler breeders to relinquish a food reward by moving to another area of the gas chamber in response to aversive stimuli. They were then stunned and subsequently killed using single exposure to either CO₂, N₂, LAPS or medical air as a control. Birds exposed to CO₂ relinquished the food reward the quickest and exhibited gasping and headshaking more than the other groups. LAPS resulted in the quickest time to loss of posture (LOP) and birds in the N₂ group took the longest. Birds exposed to N₂ displayed the longest duration of ataxia of any group; however, they did not show any wing-flapping prior to LOP, unlike the LAPS and CO₂. Collectively these data demonstrate that both LAPS and N₂ are less aversive to poultry than CO₂ and may offer a significant welfare refinement for poultry killed for meat production.

中文翻译：

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使用单一厌恶测试范例评估低气压，二氧化碳或氮气下的家禽惊呆状态。

已建议在屠宰场中的4 kg以下家禽中使用低气压击晕（LAPS），作为二氧化碳（CO ₂）的更人道替代品。但是，目前尚无研究可以直接比较两种方法之间的厌恶。在这里，我们培训了成年雌性肉鸡种鸡，以通过响应厌恶刺激而移至气室的另一个区域来放弃食物奖励。然后将它们震惊并随后使用一次暴露于CO ₂，N ₂，LAPS或医用空气作为对照将其杀死。鸟类暴露于CO ₂最快地放弃食物奖励，并且比其他群体表现出更多的喘气和摇头。LAPS导致失去姿势（LOP）的时间最快，而N ₂组的鸟类花费的时间最长。暴露于N _2的鸟类显示出任何一组中共济失调的时间最长；但是，与LAPS和CO ₂不同，它们在LOP之前没有出现任何机翼拍打。总的来说，这些数据表明，LAPS和N ₂对家禽的厌恶性都比CO _2小，并且可以为肉类生产中杀死的家禽提供显着的福利改善。