Department of Animal and Food Sciences, University of Delaware, Newark 19716, USA.
Poult Sci. 2012 Dec;91(12):3057-64. doi: 10.3382/ps.2012-02514.
The mass depopulation of production birds remains an effective means of controlling fast-moving, highly infectious diseases such as avian influenza and virulent Newcastle disease. Two experiments were performed to compare the physiological responses of White Pekin commercial ducks during foam depopulation and CO(2) gas depopulation. Both experiment 1 (5 to 9 wk of age) and 2 (8 to 14 wk of age) used electroencephalogram, electrocardiogram, and accelerometer to monitor and evaluate the difference in time to unconsciousness, motion cessation, brain death, altered terminal cardiac activity, duration of bradycardia, and elapsed time from onset of bradycardia to onset of unconsciousness between foam and CO(2) gas. Experiment 2 also added a third treatment, foam + atropine injection, to evaluate the effect of suppressing bradycardia. Experiment 1 resulted in significantly shorter times for all 6 physiological points for CO(2) gas compared with foam, whereas experiment 2 found that there were no significant differences between foam and CO(2) gas for these physiological points except brain death, in which CO(2) was significantly faster than foam and duration of bradycardia, which was shorter for CO(2). Experiment 2 also determined there was a significant positive correlation between duration of bradycardia and time to unconsciousness, motion cessation, brain death, and altered terminal cardiac activity. The time to unconsciousness, motion cessation, brain death, and altered terminal cardiac activity was significantly faster for the treatment foam + atropine injection compared with foam. Both experiments showed that bradycardia can occur as a result of either submersion in foam or exposure to CO(2) gas. The duration of bradycardia has a significant impact on the time it takes White Pekin ducks to reach unconsciousness and death during depopulation.
大规模扑杀生产禽鸟仍然是控制禽流感和强毒新城疫等快速传播、高度传染性疾病的有效手段。本研究进行了两项实验，比较了泡沫和 CO2 气体扑杀对商品白来航鸭的生理反应。实验 1（5-9 周龄）和实验 2（8-14 周龄）均使用脑电图、心电图和加速度计监测和评估泡沫和 CO2 气体在无意识时间、运动停止时间、脑死亡时间、终末心搏活动改变、心动过缓持续时间和心动过缓开始到无意识开始的时间之间的差异。实验 2 还增加了第三个处理，即泡沫+阿托品注射，以评估抑制心动过缓的效果。实验 1 结果显示，CO2 气体在所有 6 个生理指标上的时间都明显短于泡沫，而实验 2 发现，除脑死亡外，泡沫和 CO2 气体在这些生理指标上没有显著差异，CO2 气体的脑死亡时间明显快于泡沫，心动过缓持续时间短于泡沫。实验 2 还确定，心动过缓持续时间与无意识时间、运动停止时间、脑死亡时间和终末心搏活动改变之间存在显著正相关。与泡沫相比，泡沫+阿托品注射的处理使无意识时间、运动停止时间、脑死亡时间和终末心搏活动改变的时间显著缩短。两项实验均表明，无论是浸泡在泡沫中还是暴露在 CO2 气体中，都可能导致心动过缓。心动过缓的持续时间对商品白来航鸭在扑杀过程中达到无意识和死亡的时间有显著影响。
