Programa de Pós-graduação em Zootecnia, Faculdade de Ciências Agrárias e Veterinárias, UNESP - São Paulo State University, Jaboticabal, SP, Brazil.
Maneja Bem-estar animal, MANEJA, Concórdia, SC, Brazil.
J Anim Sci. 2020 Jul 1;98(7). doi: 10.1093/jas/skaa204.
Twenty-seven neonate piglets (range from 0.35 to 1.17 kg) were evaluated for the effectiveness of blunt force trauma as a method of on-farm cull. Brainstem function, brain injury, and hemorrhage scores (increasing from 0 to 3) were assessed after striking the head against a concrete floor. Electroencephalograms (EEG) from a subset of 15 piglets were recorded before and after blunt force trauma for electrophysiological assessments. Blunt force trauma was performed by a single experienced farmer in a commercial farm by holding the piglet by its both hind legs and striking the head against the concrete floor. All piglets remained recumbent and did not show brainstem reflexes. Only one piglet did not presented tonic/clonic physical activity. The mean time to the onset of persistent isoelectric EEG was 64.3 ± 7.3 s (range 18 to 115). Total power, theta, alpha, and beta power decreased to approximately 45%, 30%, 20%, and 15% from pretreatment power, respectively, by 15-s post-impact. There were no periods of normal-like EEG after the culling. Bruises in the neck and shoulder were found in 67% and 70% of piglets, respectively. All piglets presented skull fractures with 20% having the nasal bone(s) fractured. Brain damage was found in all piglets, mainly in the frontal lobe(s). The occipital lobe(s) presented the greatest frequency of severe damage. The analysis of the radiographs also found a high frequency of fractures in this region. Hemorrhage was most frequent in the frontal, parietal, occipital lobes, and midbrain. When performed correctly with the appropriate weight class, blunt force trauma can be used as an effective method for the on-farm killing of nursing piglets resulting in death. However, this method should not be promoted over more reliable and repeatable cull methods such as captive bolt gun. As with blunt force trauma, there is a significant potential for animal welfare harm associated with inappropriate practice, lack of accuracy, issues with repeatability, and operator fatigue.
27 头新生仔猪（体重范围为 0.35 至 1.17 公斤）被评估使用钝力创伤作为一种在农场进行淘汰的方法的有效性。在将头部撞击混凝土地面后，评估脑干功能、脑损伤和出血评分（从 0 增加到 3）。从 15 头仔猪中选择了一部分进行脑电图（EEG）记录，在进行钝力创伤前后进行电生理评估。在商业农场中，由一名经验丰富的农民通过抓住仔猪的两条后腿并将其头部撞击混凝土地面来进行钝力创伤。所有仔猪仍然仰卧，没有表现出脑干反射。只有一头仔猪没有出现强直性阵挛性身体活动。持续等电 EEG 发作的平均时间为 64.3 ± 7.3 秒（范围为 18 至 115 秒）。总功率、θ 波、α 波和 β 波分别下降到预处理功率的约 45%、30%、20%和 15%，在冲击后 15 秒。在淘汰后没有出现正常样 EEG 的时期。在 67%和 70%的仔猪中分别发现颈部和肩部有瘀伤。所有仔猪均出现颅骨骨折，其中 20%的仔猪鼻骨骨折。所有仔猪均发现脑损伤，主要位于额叶。枕叶（s）出现最严重损伤的频率最高。对 X 光片的分析还发现该区域骨折的频率很高。在额、顶、枕叶和中脑，出血最常见。使用适当的体重等级正确进行时，钝力创伤可作为一种有效的方法，用于在农场杀死哺乳仔猪，导致其死亡。然而，与更可靠和可重复的淘汰方法（如击晕枪）相比，这种方法不应该被推广。与钝力创伤一样，由于不适当的实践、缺乏准确性、可重复性问题和操作人员疲劳等原因，存在严重的动物福利危害。
