Livestock Research of Wageningen UR, 8200 AB Lelystad, the Netherlands.
Poult Sci. 2010 Dec;89(12):2551-8. doi: 10.3382/ps.2010-00815.
Behavioral and neural responses of 47 broilers to head-only single-bird electrical stunning were evaluated using cone-shaped restrainers in which the broilers were suspended by their feet. Meat quality assessment was performed on 2 groups of 25 broilers stunned using the head-only method or a conventional water bath method. Hemorrhages were quantified by a visual grading system. On electroencephalogram recordings, a general epileptiform insult was observed when a set current of at least 190 mA (~100 V, 50 Hz) was applied for a duration of 0.5, 3, or 5 s. This insult showed a tonic phase, followed by a clonic phase and an exhaustion phase, after which the birds recovered. On the basis of visual observation, these birds may have been unconscious for approximately 30, 44, or 65 s. According to correlation dimension analysis scores, these durations were 18, 12, and 16 s, respectively. Within a confidence limit of 95%, taking into account the number of birds with a reliable electroencephalogram, the chance of an effective stun lies between 0.95 and 1.00 with an average current of 190 ± 30 mA. After stunning, the electrocardiogram revealed fibrillation. The heart rate decreased significantly (P < 0.05) after stunning but recovered thereafter. The pH after chilling was (P < 0.05) lower in the group stunned head only compared with the water bath group. The percentages of fillets free of blood splashes were 80% in carcasses of head-only-stunned birds and 16% in carcasses from broilers stunned in the commercial water bath. It was concluded that broilers were insensible and unconscious after head-only electrical stunning using pin-electrodes. Because of the risk that broilers can rapidly regain consciousness after stunning, cutting the neck immediately after stunning is recommended. It is also recommended that the head-only equipment be developed further for practical application and commercial use.
采用锥形束缚器对 47 只肉鸡进行单头电击晕的行为和神经反应进行了评估，肉鸡的脚被悬挂在束缚器中。对使用头部电击晕方法或传统水浴法进行电击晕的两组 25 只肉鸡进行了肉质评估。通过视觉评分系统对出血进行了量化。在脑电图记录中，当施加至少 190 mA（~100 V，50 Hz）的设定电流持续 0.5、3 或 5 s 时，观察到一般癫痫样刺激。该刺激显示强直相，随后是阵挛相和衰竭相，之后鸟类恢复。根据视觉观察，这些鸟类可能处于无意识状态约 30、44 或 65 s。根据关联维数分析得分，这些时间分别为 18、12 和 16 s。在置信度为 95%的情况下，考虑到具有可靠脑电图的鸟类数量，有效电击晕的机会在 0.95 到 1.00 之间，平均电流为 190 ± 30 mA。电击晕后，心电图显示纤维颤动。心率在电击晕后显著降低（P < 0.05），但随后恢复。冷却后的 pH 值在仅头部电击晕组中（P < 0.05）低于水浴组。仅头部电击晕组的无血溅肉片百分比为 80%，而商业水浴组的肉鸡为 16%。研究结论为，采用插电电极对肉鸡进行单头电击晕后，鸡处于无意识和昏迷状态。由于电击晕后肉鸡可能迅速恢复意识的风险，建议在电击晕后立即切断颈部。还建议进一步开发仅头部设备，以便实际应用和商业使用。
