Zenth Friederike, Morocutti Elena, Palme Rupert, Nicoloso Sandro, Giacomelli Stefano, Macho-Maschler Sabine, Storch Ilse, Corlatti Luca
Chair of Wildlife Ecology and Management University of Freiburg Freiburg im Breisgau Germany.
Department of Life Sciences University of Siena Siena Italy.
Ecol Evol. 2025 Jan 29;15(2):e70662. doi: 10.1002/ece3.70662. eCollection 2025 Feb.
Faecal cortisol/corticosterone metabolites (FCMs) have become increasingly popular as an easy-to-sample, non-invasive and feedback-free alternative to assess glucocorticoid (GC) levels, key components of the neuroendocrine stress response and other physiological processes. While FCMs can be a powerful aid, for instance, for gaining insights into ecological and evolutionary processes, as well as to assess animal welfare or impacts of anthropogenic stressors on wildlife populations, this method comes with specific challenges. Because GCs are heavily metabolised before excretion, it is critical to validate the enzyme immunoassays (EIAs) used to measure FCMs. Additionally, because species may differ in metabolite profiles, assay validation must be performed separately for each focal species. Despite this, the use of unvalidated assays remains widespread. We performed a biological validation experiment to test a set of EIAs to measure FCMs and adrenocortical activity in free-living Alpine marmots . We capitalised on capture and handling as part of a relocation project of marmots under the assumption that capture, and handling represent a stressful event and tracked changes in FCM levels over the following 48 h. Faeces samples collected at capture were assumed to return baseline FCM levels. Of the three EIAs tested, only the 11-oxoetiocholanolone '72T' EIA detected an increase in FCM levels about 18 h after capture. This result paves the way for future studies using FCMs to investigate the adrenocortical activity in this species.
粪便皮质醇/皮质酮代谢物（FCMs）作为一种易于采集、非侵入性且无反馈的替代方法，用于评估糖皮质激素（GC）水平，已越来越受欢迎。糖皮质激素是神经内分泌应激反应和其他生理过程的关键组成部分。例如，虽然FCMs可以有力地帮助我们深入了解生态和进化过程，以及评估动物福利或人为应激源对野生动物种群的影响，但这种方法也面临着特定的挑战。由于糖皮质激素在排泄前会大量代谢，因此验证用于测量FCMs的酶免疫分析（EIA）至关重要。此外，由于不同物种的代谢物谱可能不同，必须针对每个目标物种分别进行分析验证。尽管如此，使用未经验证的分析方法仍然很普遍。我们进行了一项生物学验证实验，以测试一组用于测量自由生活的阿尔卑斯旱獭粪便中FCMs和肾上腺皮质活性的EIA。我们利用捕获和处理作为旱獭迁移项目的一部分，假设捕获和处理代表应激事件，并跟踪接下来48小时内FCMs水平的变化。捕获时收集的粪便样本被认为反映了FCMs的基线水平。在测试的三种EIA中，只有11-氧代雄烷醇酮“72T”EIA检测到捕获后约18小时FCMs水平有所升高。这一结果为未来使用FCMs研究该物种肾上腺皮质活性的研究铺平了道路。
