Espinoza Crystal, Lomax Sabrina, Windsor Peter
School of Life and Environmental Sciences, Faculty of Science, The University of Sydney, Sydney 2006, Australia.
Sydney School of Veterinary Science, Faculty of Science, The University of Sydney, Sydney 2006, Australia.
Animals (Basel). 2020 Feb 17;10(2):312. doi: 10.3390/ani10020312.
Dehorning causes pain and distress to cattle, and there is a need to provide effective and practical analgesia to improve animal welfare. We conducted an experiment to determine the effect of a modified post-operative topical wound management formulation containing two local anaesthetics (TA) on the plasma cortisol concentration (PCC) of scoop-dehorned calves. Two months old Holstein-Friesian heifer calves ( = 30) were randomly allocated to sham dehorning control (CON), scoop dehorning (D), or scoop dehorning with immediate post-operative application of the TA (DTA). Blood samples were obtained via jugular venepuncture prior to sham or actual dehorning, and 40 min, 1.5, 4 and 24 h later. PCC changed significantly over time ( < 0.01). There was a trend for lower PCC in DTA calves compared to D calves ( = 0.09), with the PCC area under the curve lowest in CON calves as compared to D and DTA calves ( = 0.02). Cortisol concentrations were similar between D and DTA at all time points. The TA did not reduce cortisol concentrations up to 24 h following treatment and the cortisol response likely reflects the pain induced by the procedure, the effect of handling and restraint, and haemorrhaging which limited adherence of the TA actives. A multimodal analgesic approach, as assessed through multiple pain indicators, should be the focus of future work.
去角会给牛带来疼痛和痛苦，因此需要提供有效且实用的镇痛措施以改善动物福利。我们进行了一项实验，以确定一种含有两种局部麻醉剂的改良术后局部伤口处理配方（TA）对用铲子去角犊牛血浆皮质醇浓度（PCC）的影响。将30头两个月大的荷斯坦 - 弗里生小母牛犊牛随机分配到假去角对照组（CON）、铲子去角组（D）或铲子去角并在术后立即应用TA的组（DTA）。在假去角或实际去角前以及之后40分钟、1.5小时、4小时和24小时，通过颈静脉穿刺采集血样。PCC随时间有显著变化（<0.01）。与D组犊牛相比，DTA组犊牛的PCC有降低趋势（=0.09），与D组和DTA组犊牛相比，CON组犊牛曲线下的PCC面积最低（=0.02）。在所有时间点，D组和DTA组的皮质醇浓度相似。治疗后24小时内TA并未降低皮质醇浓度，皮质醇反应可能反映了手术引起的疼痛、处理和约束的影响以及出血，而出血限制了TA活性成分的附着。通过多种疼痛指标评估，多模式镇痛方法应成为未来工作的重点。
