Braga Goncalves Ines, Heistermann Michael, Santema Peter, Dantzer Ben, Mausbach Jelena, Ganswindt Andre, Manser Marta B
Department of Evolutionary Biology and Environmental Studies, Animal Behaviour, University of Zurich, Winterthurerstrasse 190, 8057, Zürich, Switzerland.
Endocrinology Laboratory, German Primate Center, Kellnerweg 4, D-37077, Göttingen, Germany.
PLoS One. 2016 Apr 14;11(4):e0153161. doi: 10.1371/journal.pone.0153161. eCollection 2016.
In mammals, glucocorticoid (i.e. GC) levels have been associated with specific life-history stages and transitions, reproductive strategies, and a plethora of behaviors. Assessment of adrenocortical activity via measurement of glucocorticoid metabolites in feces (FGCM) has greatly facilitated data collection from wild animals, due to its non-invasive nature, and thus has become an established tool in behavioral ecology and conservation biology. The aim of our study was to validate a fecal glucocorticoid assay for assessing adrenocortical activity in meerkats (Suricata suricatta), by comparing the suitability of three GC enzyme immunoassays (corticosterone, 11β-hydroxyetiocholanolone and 11oxo-etiocholanolone) in detecting FGCM increases in adult males and females following a pharmacological challenge with adrenocorticotropic hormone (ACTH) and biological stimuli. In addition, we investigated the time course characterizing FGCM excretion, the effect of age, sex and time of day on FGCM levels and assessed the potential effects of soil contamination (sand) on FGCM patterns. Our results show that the group specific 11β-hydroxyetiocholanolone assay was most sensitive to FGCM alterations, detecting significant and most distinctive elevations in FGCM levels around 25 h after ACTH administration. We found no age and sex differences in basal FGCM or on peak response levels to ACTH, but a marked diurnal pattern, with FGCM levels being substantially higher in the morning than later during the day. Soil contamination did not significantly affect FGCM patterns. Our results emphasize the importance of conducting assay validations to characterize species-specific endocrine excretion patterns, a crucial step to all animal endocrinology studies using a non-invasive approach.
在哺乳动物中，糖皮质激素（即GC）水平与特定的生命史阶段及转变、繁殖策略以及众多行为相关联。通过测量粪便中的糖皮质激素代谢物（FGCM）来评估肾上腺皮质活动，因其具有非侵入性，极大地便利了从野生动物收集数据，因此已成为行为生态学和保护生物学中的一项既定工具。我们研究的目的是通过比较三种GC酶免疫测定法（皮质酮、11β-羟基表雄酮和11-氧代表雄酮）在检测成年雄性和雌性接受促肾上腺皮质激素（ACTH）药理刺激和生物刺激后FGCM增加方面的适用性，来验证一种用于评估狐獴（Suricata suricatta）肾上腺皮质活动的粪便糖皮质激素测定法。此外，我们研究了FGCM排泄的时间进程、年龄、性别和时间对FGCM水平的影响，并评估了土壤污染（沙子）对FGCM模式的潜在影响。我们的结果表明，组特异性的11β-羟基表雄酮测定法对FGCM变化最为敏感，在注射ACTH后约25小时检测到FGCM水平有显著且最明显的升高。我们发现基础FGCM或对ACTH的峰值反应水平在年龄和性别上没有差异，但存在明显的昼夜模式，早晨的FGCM水平显著高于当天晚些时候。土壤污染并未显著影响FGCM模式。我们的结果强调了进行测定法验证以表征物种特异性内分泌排泄模式的重要性，这是所有使用非侵入性方法的动物内分泌学研究的关键步骤。
