Feral swine are a highly destructive invasive species around the globe. Wildlife managers commonly trap and euthanize feral swine with firearms to reduce their adverse impacts. The utility of euthanizing domestic swine with firearms has been considered when emergency situations arise such as in the event of a foreign animal disease outbreak in domestic swine. Similarly, the rapid depopulation of domestic swine facilities became necessary when the COVID-19 pandemic disrupted pork production in 2020. Evaluation of the effects of caliber, cartridge, size of feral swine, and shot placement on effectiveness and safety of the method is needed. We collected data from feral swine euthanized in traps on how those variables influenced the effectiveness in time to death and number of shots required and safety risks based on the occurrence of bullet pass-through (i.e., bullet exiting the pig). We tested 3 cartridges of 2 calibers (0.22 long rifle, 0.22 Winchester magnum rimfire, and 0.308 Winchester) delivered from a rifle with 3 shot placements targeting the brain. From 570 euthanization events, we calculated an average time to death of 100.06 (SD = 29.24) s, with larger feral swine taking slightly longer. Most feral swine (73%) were euthanized with a single shot but averaged 1.28 (SD = 0.48) shots overall. Safety risks from pass-through shots were more common when using the 0.308 Winchester cartridge, and when rear and side shot placements were used. Overall, we recommend a 0.22 long rifle cartridge and frontal shot placement as an effective and safe option for euthanizing feral swine in traps, and likely for domestic swine of similar size and shot distances.

中文翻译：

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在陷阱中对野猪 （Sus scrofa） 实施安乐死的步枪弹药筒和射击位置的评估


野猪是全球极具破坏性的入侵物种。野生动物管理者通常用枪支诱捕和安乐死野猪，以减少它们的不利影响。当出现紧急情况时，例如在家猪中爆发外来动物疾病时，已经考虑了用枪支对家猪实施安乐死的效用。同样，当 COVID-19 大流行在 2020 年扰乱了猪肉生产时，国内养猪设施的快速减少变得必要。需要评估口径、弹药筒、野猪大小和注射位置对该方法有效性和安全性的影响。我们从在陷阱中安乐死的野猪中收集了数据，了解这些变量如何影响死亡时间和所需射击次数的有效性，以及基于子弹穿过（即子弹离开猪）发生的安全风险。我们测试了从步枪发射的 3 个 2 口径弹药筒（0.22 长步枪、0.22 温彻斯特马格南边缘火和 0.308 温彻斯特），其中 3 发子弹瞄准大脑。从 570 次安乐死事件中，我们计算出平均死亡时间为 100.06 （SD = 29.24） s，较大的野猪需要的时间略长。大多数野猪 （73%） 被一次性安乐死，但总体平均为 1.28 （SD = 0.48）。当使用 0.308 Winchester 弹药筒以及使用后弹和侧弹位置时，传递弹丸的安全风险更为常见。总体而言，我们建议使用 0.22 长的步枪弹药筒和正面射击放置，作为对陷阱中的野猪实施安乐死的有效且安全的选择，并且可能适用于类似大小和射击距离的家猪。