Wheeler Brandon C, Tiddi Barbara, Kalbitzer Urs, Visalberghi Elisabetta, Heistermann Michael
Cognitive Ethology Laboratory, German Primate Center, 37077 Göttingen, Germany ; Courant Research Centre Evolution of Social Behaviour, University of Göttingen, 37077 Göttingen, Germany.
Int J Primatol. 2013;34(5):879-898. doi: 10.1007/s10764-013-9703-y. Epub 2013 Aug 16.
Analysis of fecal glucocorticoid (GC) metabolites has recently become the standard method to monitor adrenocortical activity in primates noninvasively. However, given variation in the production, metabolism, and excretion of GCs across species and even between sexes, there are no standard methods that are universally applicable. In particular, it is important to validate assays intended to measure GC production, test extraction and storage procedures, and consider the time course of GC metabolite excretion relative to the production and circulation of the native hormones. This study examines these four methodological aspects of fecal GC metabolite analysis in tufted capuchins (). Specifically, we conducted an adrenocorticotrophic hormone (ACTH) challenge on one male and one female capuchin to test the validity of four GC enzyme immunoassays (EIAs) and document the time course characterizing GC metabolite excretion in this species. In addition, we compare a common field-friendly technique for extracting fecal GC metabolites to an established laboratory extraction methodology and test for effects of storing "field extracts" for up to 1 yr. Results suggest that a corticosterone EIA is most sensitive to changes in GC production, provides reliable measures when extracted according to the field method, and measures GC metabolites which remain highly stable after even 12 mo of storage. Further, the time course of GC metabolite excretion is shorter than that described yet for any primate taxa. These results provide guidelines for studies of GCs in tufted capuchins, and underscore the importance of validating methods for fecal hormone analysis for each species of interest.
粪便糖皮质激素（GC）代谢物分析最近已成为非侵入性监测灵长类动物肾上腺皮质活动的标准方法。然而，鉴于GC在不同物种甚至不同性别之间的产生、代谢和排泄存在差异，目前尚无普遍适用的标准方法。特别是，验证旨在测量GC产生的检测方法、测试提取和储存程序，并考虑GC代谢物排泄相对于天然激素产生和循环的时间过程非常重要。本研究考察了簇绒卷尾猴粪便GC代谢物分析的这四个方法学方面。具体而言，我们对一只雄性和一只雌性卷尾猴进行了促肾上腺皮质激素（ACTH）刺激，以测试四种GC酶免疫分析（EIA）的有效性，并记录该物种GC代谢物排泄的时间过程。此外，我们将一种常见的便于野外操作的粪便GC代谢物提取技术与一种成熟的实验室提取方法进行了比较，并测试了“野外提取物”储存长达1年的影响。结果表明，皮质酮EIA对GC产生的变化最敏感，按照野外方法提取时能提供可靠的测量结果，并且能测量即使储存12个月后仍保持高度稳定的GC代谢物。此外，GC代谢物排泄的时间过程比迄今描述的任何灵长类类群都要短。这些结果为簇绒卷尾猴GC研究提供了指导方针，并强调了针对每种感兴趣的物种验证粪便激素分析方法的重要性。
