Euthanasia methods, corticosterone and haematocrit levels in Xenopus laevis: evidence for differences in stress?
Euthanasia methods, corticosterone and haematocrit levels in Xenopus laevis: evidence for differences in stress?
复制标题
非洲爪蟾的安乐死方法、皮质酮和血细胞比容水平：压力差异的证据？
作者：
G. A. Archard;A. Goldsmith
两栖动物，像其他脊椎动物一样，通过释放糖皮质激素类固醇激素来调节对压力的生理和行为反应。应激激素的测量为改善实验动物的福利提供了一种潜在的手段。例如，实验室的住房和程序的操作结合糖皮质激素的测量可以确定哪些条件下更紧张的动物。这一点很重要，因为很少有实验证据来指导两栖动物和其他低等脊椎动物的福利最佳实践。我们研究了不同方法的安乐死对循环血浆皮质酮水平的非洲爪蛙（非洲爪蟾），一种模型两栖动物的有机体，经常在实验室中使用的效果。特别是，我们研究了不同浓度和pH值的麻醉剂甲基磺酸三卡因（MS-222）的效果。MS-222的低浓度和未缓冲（低pH值）溶液导致皮质酮水平升高，但仅在考虑MS-222处理对血液体积的影响后。动物所经历的干扰水平也会影响皮质酮水平。因此，我们的数据表明，为了使X的应力最小化。在最小干扰后，应将动物置于3 g L-1 MS-222溶液（缓冲至pH 7）中实施安乐死。两栖动物福利使用皮质酮措施作为一种工具的改善潜力进行了讨论。
Amphibians, like other vertebrates, respond to acute stressors by releasing glucocorticoid steroid hormones that mediate physiological and behavioural responses to stress. Measurement of stress hormones provides a potential means to improve the welfare of laboratory animals. For example, manipulations of laboratory housing and procedures combined with measurement of glucocorticoids may identify which conditions are more stressful to animals. This is important because there is very little experimental evidence to guide best practice for welfare in amphibians and other lower vertebrates. We investigated the effect of different methods of euthanasia on the circulating plasma corticosterone levels in the African clawed frog (Xenopus laevis), a model amphibian organism that is frequently used in laboratories. In particular, we investigated the effect of different concentrations and pH of the anaesthetic tricaine methanesulphonate (MS-222). Low concentration and unbuffered (low pH) solutions of MS-222 caused elevated corticosterone levels, but only after the effect of MS-222 treatment on blood fluid volume had been taken into account. The level of disturbance that animals experienced also affected corticosterone levels. Thus, our data suggest that to minimise stress to X. laevis, animals should be euthanised after minimal disturbance and in a 3 g L−1 MS-222 solution, buffered to pH 7. The potential for the improvement of amphibian welfare using corticosterone measures as a tool is discussed.