Wasser S K, Papageorge S, Foley C, Brown J L
Center for Wildlife Conservation, Seattle, Washington 98103-5897, USA.
Gen Comp Endocrinol. 1996 May;102(2):255-62. doi: 10.1006/gcen.1996.0067.
We developed and validated a noninvasive method to quantify fecal estrogens and progestins as a tool for monitoring long-term ovarian activity in free-ranging African elephants. The lag times between iv injection of [(3)H]estradiol and [(14)C]progesterone and peak excretion of radioactivity in urine and feces were approximately 4 hr and 48 hr, respectively. The majority of progesterone metabolites recovered was excreted in feces (55%) versus urine (45%), whereas comparatively little of the recovered estradiol metabolites were excreted in feces (5%) compared to urine (95%). Intrasample variation in fecal hormone concentrations was extremely high but could be substantially reduced by extracting well-mixed fecal powder from freeze-dried samples, taken from the central or premixed portion of the wet sample. This method resulted in a close correspondence between matched serum and fecal progestins (mean correlation = 0.81, range 0.61-0.94) collected from five nonpregnant adult females over a 7-month period. Fecal estrogen profiles were more ambiguous, tending to overlap with those of fecal progestins. We conclude that analyses of fecal progestins can provide an effective, noninvasive means of characterizing ovarian activity in free-ranging African elephants.
我们开发并验证了一种用于定量粪便中雌激素和孕激素的非侵入性方法，以此作为监测自由放养的非洲象长期卵巢活动的工具。静脉注射[³H]雌二醇和[¹⁴C]孕酮后，尿液和粪便中放射性峰值排泄的滞后时间分别约为4小时和48小时。回收的孕酮代谢物大部分通过粪便排泄（55%），而尿液排泄占45%；相比之下，回收的雌二醇代谢物通过粪便排泄的比例相对较少（5%），尿液排泄占95%。粪便激素浓度的样本内变异极高，但通过从冻干样本中提取充分混合的粪便粉末（取自湿样本的中部或预混合部分），变异可大幅降低。该方法使得在7个月期间从5只未怀孕成年雌性大象收集的配对血清和粪便孕激素之间具有密切的对应关系（平均相关性 = 0.81，范围0.61 - 0.94）。粪便雌激素谱更不明确，倾向于与粪便孕激素谱重叠。我们得出结论，粪便孕激素分析可以提供一种有效、非侵入性的手段来表征自由放养的非洲象的卵巢活动。
