Ash Hayley, Smith Tessa E, Knight Simon, Buchanan-Smith Hannah M
Behaviour and Evolution Research Group, Scottish Primate Research Group, Psychology, Faculty of Natural Sciences, University of Stirling, Scotland, UK.
Department of Biology, University of Chester, Parkgate Road, Chester, England, UK.
Physiol Behav. 2018 Mar 1;185:14-22. doi: 10.1016/j.physbeh.2017.12.018. Epub 2017 Dec 15.
Cortisol levels are often used as a physiological measure of the stress response in captive primates, with non-invasive measures of this being an important step in welfare assessment. We report a method of collecting saliva samples voluntarily from unrestrained captive common marmosets (Callithrix jacchus), and validate an enzyme-linked immunosorbent assay (ELISA) technique previously unused in this species. Saliva samples were collected from marmosets housed in pairs in a UK laboratory. The assay showed parallelism, precision, accuracy and sensitivity, meeting the criteria typically used to investigate the effectiveness of new analytical techniques. Use of Salimetrics® Oral Swabs considerably increased the amount of cortisol recovered in comparison with previous studies using cotton buds. However, while use of banana on the swabs can encourage chewing, it may influence results. Although increases in cortisol levels have traditionally been interpreted as an indicator of stress in primates, there are many factors that affect the hypothalamic-pituitary-adrenal axis, with some studies showing decreases in cortisol levels post-stressor. Following a likely stressful event (capture for weighing), we also found cortisol levels significantly decreased, possibly due to social buffering or 'blunting' of the HPA axis. Order of weighing also had an effect. The method therefore provided an effective non-invasive means of assessing acute changes in cortisol level that may be more useful than previous methods, improving our ability to study physiological aspects of welfare in primates. We discuss methodological considerations, as well as implications of using cortisol as a measure of stress.
皮质醇水平常被用作圈养灵长类动物应激反应的生理指标,对此进行非侵入性测量是福利评估中的重要一步。我们报告了一种从不受约束的圈养普通狨猴(Callithrix jacchus)中自愿采集唾液样本的方法,并验证了一种此前未在该物种中使用过的酶联免疫吸附测定(ELISA)技术。唾液样本是从英国一家实验室中成对饲养的狨猴中采集的。该测定显示出平行性、精密度、准确性和灵敏度,符合通常用于研究新分析技术有效性的标准。与之前使用棉签的研究相比,使用Salimetrics®口腔拭子大大增加了回收的皮质醇量。然而,虽然在拭子上使用香蕉可以促使狨猴咀嚼,但这可能会影响结果。传统上,皮质醇水平的升高被解释为灵长类动物应激的指标,但有许多因素会影响下丘脑 - 垂体 - 肾上腺轴,一些研究表明应激源出现后皮质醇水平会下降。在经历了一次可能有压力 的事件(捕捉称重)后,我们还发现皮质醇水平显著下降,这可能是由于社会缓冲或下丘脑 - 垂体 - 肾上腺轴的“钝化”。称重顺序也有影响。因此,该方法提供了一种有效的非侵入性手段来评估皮质醇水平的急性变化,可能比以前的方法更有用,提高了我们研究灵长类动物福利生理方面的能力。我们讨论了方法学上的考虑因素,以及使用皮质醇作为应激指标的意义。