Steybe Linda, Kress Kevin, Schmucker Sonja, Stefanski Volker
Department of Behavioral Physiology of Livestock, Institute of Animal Science, University of Hohenheim, Garbenstraße 17, 70599 Stuttgart, Germany.
German Genetic, Schweinezuchtverband Baden-Wuerttemberg e.V., Im Wolfer 10, 70599 Stuttgart, Germany.
Animals (Basel). 2021 Feb 26;11(3):618. doi: 10.3390/ani11030618.
The aim of this study was to investigate whether the well-known positive effects of immunocastration on the behavior and welfare of pigs persist under varying environments. One hundred forty-four male pigs were studied with regard to their sex category (EM: entire males, IC: immunocastrates, BA: barrows) and housing environment (ENR: enriched, STD: standard, MIX: repeated social mixing). The vaccination of immunocastrates included two injections at the age of 12 and 22 weeks. Regardless of the housing conditions, frequencies of sexual and fighting behavior expressed by immunocastrates shifted from boar-like to barrow-like behavior after the second immunocastration vaccination (Mixed model analysis, < 0.05). Penis biting decreased in IC after the second vaccination (Wilcoxon signed-rank tests, = 0.036) and penile injuries were lower in IC animals compared to EM (Mixed model analysis, < 0.001). Housing-dependent effects on behavior could also be observed in the animals at a relatively young age. Enriched housing showed a beneficial effect on play behavior (Chi-square test, < 0.001) and the social mixing environment reduced the number of social nosing events (Mixed model analysis, < 0.05). The positive effects of immunocastration thus are robust to all housing conditions assessed in this study.
本研究的目的是调查免疫去势对猪的行为和福利的众所周知的积极影响在不同环境下是否持续存在。对144头雄性猪进行了研究，涉及它们的性别类别（EM：未阉割公猪、IC：免疫去势猪、BA：阉割公猪）和饲养环境（ENR：丰富环境、STD：标准环境、MIX：反复社会混合）。免疫去势猪的疫苗接种包括在12周龄和22周龄时进行两次注射。无论饲养条件如何，在第二次免疫去势疫苗接种后，免疫去势猪表现出的性行为和争斗行为的频率从公猪样行为转变为阉割公猪样行为（混合模型分析，<0.05）。第二次接种疫苗后，IC组的咬阴茎行为减少（Wilcoxon符号秩检验，=0.036），与EM组相比，IC组动物的阴茎损伤更低（混合模型分析，<0.001）。在相对年轻的动物中也观察到了饲养环境对行为的影响。丰富环境对玩耍行为有有益影响（卡方检验，<0.001），社会混合环境减少了社会嗅闻事件的数量（混合模型分析，<0.05）。因此，免疫去势的积极影响对本研究评估的所有饲养条件都具有稳健性。
