Stafford K J, Mellor D J
Animal Welfare Science and Bioethics Centre, Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Private Bag 11222, Palmerston North, New Zealand.
N Z Vet J. 2005 Oct;53(5):271-8. doi: 10.1080/00480169.2005.36560.
Castration is an ancient husbandry procedure used to produce docile cattle for draught work, to reduce unwanted breeding, and to modify carcass quality. All the physical methods used to castrate cattle have side-effects and cause pain. The plasma cortisol response to castration using Burdizzo clamps and, by inference, the acute pain experienced, is less than that caused by surgical, rubber-ring or latex-band castration. The cortisol response may be influenced by the age of the animal castrated, but this has not been well defined. Local anaesthesia virtually eliminates the cortisol response, and thus the acute pain, caused by rubber-ring or latex-band castration, but needs to be combined with a systemic analgesic such as the non-steroidal anti-inflammatory drug ketoprofen to eliminate the cortisol response to Burdizzo or surgical castration. When used alone, ketoprofen sometimes reduces the cortisol response to Burdizzo or surgical castration but may need to be accompanied by local anaesthesia to eliminate the pain-induced behaviour seen during the castration process itself. Thus, pharmacological methods are available to virtually eliminate the acute pain experienced by calves during the 12 h following castration. The use of these methods is an additional cost for farmers and may be limited by the availability of drugs for farmers to use and the scarcity of veterinarians in farm animal practice.
去势是一种古老的畜牧操作，用于培育温顺的役用牛、减少不必要的繁殖以及改善胴体品质。所有用于给牛去势的物理方法都有副作用并会引起疼痛。使用布尔迪佐去势钳去势后血浆皮质醇的反应，以及由此推断出的所经历的急性疼痛，都小于手术去势、橡胶环或乳胶带去势所引起的反应。皮质醇反应可能受去势动物年龄的影响，但这一点尚未明确界定。局部麻醉实际上消除了橡胶环或乳胶带去势所引起的皮质醇反应，进而消除了急性疼痛，但需要与全身性镇痛药（如非甾体抗炎药酮洛芬）联合使用，以消除布尔迪佐或手术去势引起的皮质醇反应。单独使用时，酮洛芬有时会降低布尔迪佐或手术去势引起的皮质醇反应，但可能需要辅以局部麻醉，以消除去势过程中出现的疼痛诱发行为。因此，药理学方法实际上可以消除犊牛去势后12小时内所经历的急性疼痛。这些方法的使用对养殖户来说是一项额外成本，而且可能会受到养殖户可用药物的供应情况以及农场动物诊疗中兽医短缺的限制。
