Grandin Temple
Department of Animal Science, College of Agricultural Sciences, Colorado State University, Fort Collins 80523-1171, USA.
J Am Vet Med Assoc. 2002 Nov 1;221(9):1258-61. doi: 10.2460/javma.2002.221.1258.
To evaluate efficacy of penetrating captive bolt stunning of cattle in commercial beef slaughter plants and identify potential causes of a return to sensibility among stunned cattle.
Observational study.
21 federally inspected commercial beef slaughter plants.
In each plant, stunning of at least 100 cattle (19 large plants) or a minimum of 1 hour of production (2 small plants) was observed, and cattle were evaluated for signs of returning to sensibility on the bleed rail. Cattle with a limp, flaccid head, a lack of spontaneous blinking, and an absence of a righting reflex were considered insensible.
In 17 of the 21 (81%) plants, all cattle were rendered insensible before they were hoisted onto the bleed rail. The remaining 4 plants had cattle that had signs of returning to sensibility; these cattle were restunned prior to skinning or leg removal. Of 1,826 fed steers and heifers, 3 (0.16%) had signs of returning to sensibility, whereas 8 of 692 (1.2%) bulls and cows did. Return-to-sensibility problems were attributed to storage of stunner cartridges in damp locations, poor maintenance of firing pins, inexperience of the stunner operator (ie, shooting cattle too high on the forehead), misfiring of the stunner because of a dirty trigger, and stunning of cattle with thick, heavy skulls.
Results suggest that efficiency of captive bolt stunning of cattle in commercial slaughter plants can be safely and objectively assessed. Care should be taken to maintain stunners correctly, particularly when stunning bulls and cows with heavy skulls.
评估在商业肉牛屠宰厂中使用穿透式击晕枪对牛进行击晕的效果，并确定被击晕的牛恢复知觉的潜在原因。
观察性研究。
21家联邦检查的商业肉牛屠宰厂。
在每家工厂，观察至少100头牛的击晕情况（19家大型工厂）或至少1小时的生产过程（2家小型工厂），并在放血轨道上评估牛恢复知觉的迹象。肢体无力、头部松弛、无自主眨眼且无翻正反射的牛被视为失去知觉。
在21家工厂中的17家（81%），所有牛在被吊起至放血轨道之前均已失去知觉。其余4家工厂有牛出现恢复知觉的迹象；这些牛在剥皮或去腿之前再次被击晕。在1826头育肥牛和小母牛中，有3头（0.16%）出现恢复知觉的迹象，而在692头公牛和母牛中有8头（1.2%）出现此情况。恢复知觉的问题归因于击晕枪弹药筒存放在潮湿的地方、撞针维护不佳、击晕枪操作员缺乏经验（即在前额过高位置射击牛）、扳机脏污导致击晕枪误发以及对颅骨厚且重的牛进行击晕。
结果表明，商业屠宰厂中对牛使用击晕枪的效率可以安全、客观地评估。应注意正确维护击晕枪，尤其是在对颅骨重的公牛和母牛进行击晕时。
