Morrison Rebecca, Hemsworth Paul
Rivalea (Australia), Research and Innovation, Redlands Road, Corowa, NSW 2640, Australia.
Animal Welfare Science Centre, Faculty of Veterinary and Agricultural Sciences, University of Melbourne, Parkville, VIC 3010, Australia.
Animals (Basel). 2020 Sep 20;10(9):1701. doi: 10.3390/ani10091701.
This experiment assessed the efficacy of the cauterisation procedure with or without pain relief (injectable meloxicam) in mitigating the acute stress response to tail docking. Male piglets ( = 432) were allocated to the following treatments at 2-d post-farrowing: (1) no handling, (2) sham handling, (3) tail docked using clippers, (4) tail docked using a cauteriser, (5) meloxicam + clipper, and (6) meloxicam + cauteriser. Meloxicam treatments used Metacam at 5 mg/mL injected i.m. 1 h prior to tail docking. Blood samples were collected at 15 and 30 min post-treatment and analysed for total plasma cortisol. Behaviours indicative of pain such as escape attempts, vocalisations and standing with head lowered were measured. The duration of vocalisations and frequency of escape attempts during treatment were greater in all tail docking treatments compared to the sham treatment. Piglets in the clipper treatment had higher ( < 0.05) cortisol concentrations at 30 min but not 15 min after treatment and stood for longer ( < 0.001) with head lowered in the first 60 min after treatment than those in the cauterisation treatment. Meloxicam reduced ( < 0.05) both the cortisol response at 30 min after tail docking with the clipper as well as the behavioural response in the first 60 min after tail docking with the clipper. In comparison to the sham treatment, cortisol concentrations at 15 min were higher in the two tail docking treatments whereas the tail docking treatments with meloxicam were similar to the sham handling treatment. In comparison to the sham handling treatment, cortisol concentrations at 30 min post-docking were higher ( < 0.05) only in the clipper treatment. While cauterisation appears to be less aversive than the clipper procedure, the administration of meloxicam did not mitigate the behavioural response during tail docking using either procedure, but reduced standing with head lowered in the first hour after docking for both methods. The commercial viability of administration of meloxicam requires consideration before it is recommended for use compared to cauterisation alone, as it requires additional handling of piglets and costs.
本实验评估了有无疼痛缓解措施（注射用美洛昔康）的烧灼术在减轻断尾急性应激反应方面的效果。将432头雄性仔猪在分娩后2天分配到以下处理组：（1）不处理，（2）假处理，（3）用剪子断尾，（4）用烧灼器断尾，（5）美洛昔康+剪子，（6）美洛昔康+烧灼器。美洛昔康处理组在断尾前1小时肌肉注射5mg/mL的美他昔康。在处理后15分钟和30分钟采集血样，分析血浆总皮质醇。测量了如逃避尝试、鸣叫和低头站立等表明疼痛的行为。与假处理相比，所有断尾处理组在处理过程中的鸣叫持续时间和逃避尝试频率都更高。剪子断尾处理组在处理后30分钟时皮质醇浓度较高（P<0.05），但在处理后15分钟时没有，且在处理后的前60分钟内低头站立的时间比烧灼术处理组更长（P<0.001）。美洛昔康降低了（P<0.05）用剪子断尾后30分钟时的皮质醇反应以及用剪子断尾后前6分钟内的行为反应。与假处理相比，两种断尾处理组在15分钟时的皮质醇浓度较高，而使用美洛昔康的断尾处理组与假处理组相似。与假处理相比，断尾后30分钟时仅剪子断尾处理组的皮质醇浓度较高（P<0.05）。虽然烧灼术似乎比剪子断尾术的厌恶程度更低，但使用美洛昔康并不能减轻使用任何一种方法断尾过程中的行为反应，但两种方法在断尾后第一小时内都减少了低头站立的情况。在推荐将美洛昔康与单独的烧灼术相比使用之前，需要考虑其商业可行性，因为它需要对仔猪进行额外处理且成本较高。
