Stead S K, Meltzer D G, Palme R
Wildlife Unit, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa.
J S Afr Vet Assoc. 2000 Sep;71(3):192-6. doi: 10.4102/jsava.v71i3.712.
Conventionally, the assessment of adrenal responses to stress relies on blood sample collection. However, blood collection from animals is impossible without restraint or immobilisation that influences results. This study was undertaken to validate recently established enzyme immunoassays that measure faecal glucocorticoid metabolites in elephants, and to perform a preliminary investigation into the biological relevance of this non-invasive method for use in assessing the degree of stress in this species. Four juvenile African elephants were injected i.m. with 2.15 mg synthetic adrenocorticotrophic hormone (Synacthen, Novartis, Switzerland). Blood and faecal samples were collected over 4 h and 7 d respectively. Concentrations of serum cortisol and faecal cortisol metabolites were determined using immunoassay. Variability of basal and peak values in blood and faeces was observed among the elephants. After ACTH injection, serum cortisol concentrations increased by 400-700%. An 11-oxoaetiocholanolone enzyme immunoassay (EIA) proved best suited to measure cortisol metabolites (11,17-dioxoandrostanes) when compared to a cortisol and corticosterone EIA in faecal samples. Concentrations of faecal 11,17-dioxoandrostanes increased by 570-1070%, reaching peak levels after 20.0-25.5 h. Greater levels of glucocorticoid metabolites were measured in faecal samples from elephants kept in small enclosures compared to levels in the faeces of animals ranging over a larger area. The results of this preliminary study suggest that non-invasive faecal monitoring of glucocorticoid metabolites is useful in investigating adrenal activity in African elephants.
传统上，评估肾上腺对应激的反应依赖于采集血样。然而，在不限制或固定动物的情况下采集血样是不可能的，而这会影响结果。本研究旨在验证最近建立的用于测量大象粪便中糖皮质激素代谢物的酶免疫测定法，并对这种非侵入性方法在评估该物种应激程度方面的生物学相关性进行初步调查。对4头非洲幼年象进行肌肉注射2.15毫克合成促肾上腺皮质激素（瑞士诺华公司的赛可同）。分别在4小时和7天内采集血样和粪便样本。使用免疫测定法测定血清皮质醇和粪便皮质醇代谢物的浓度。观察到大象之间血液和粪便中基础值和峰值的变异性。注射促肾上腺皮质激素后，血清皮质醇浓度增加了400 - 700%。与粪便样本中的皮质醇和皮质酮酶免疫测定法相比，11-氧代雄烷醇酮酶免疫测定法（EIA）被证明最适合测量皮质醇代谢物（11,17-二氧代雄烷）。粪便中11,17-二氧代雄烷的浓度增加了570 - 1070%，在20.0 - 25.5小时后达到峰值水平。与在较大区域活动的动物粪便中的水平相比，饲养在小围栏中的大象粪便样本中测量到的糖皮质激素代谢物水平更高。这项初步研究的结果表明，对糖皮质激素代谢物进行非侵入性粪便监测有助于调查非洲象的肾上腺活动。
