Leibniz-Institute for Zoo Biology and Wildlife Research, PF 601103, D-10252 Berlin, Germany.
Gen Comp Endocrinol. 2010 Jun 1;167(2):287-96. doi: 10.1016/j.ygcen.2010.03.023. Epub 2010 Mar 25.
With the increasing prevalence of faecal hormone metabolite analysis, it is important to develop a better understanding of the dynamics of faecal metabolite composition. The aim of this study was to compare the quantitative faecal gestagen and estrogen metabolite composition in the four lynx species: Eurasian lynx, Iberian lynx, Canada lynx and bobcats. Comparative HPLC immunograms were generated from faecal samples collected before, during, and after pregnancy from individual females of each lynx species. Gestagens and estrogens revealed three similar classes of immunoreactive faecal metabolites: (1) polar metabolites which were enzyme-hydrolysable and thus may be designated as conjugates, (2) non-hydrolysable polar metabolites, and (3) non-polar metabolites or free steroids. For both hormones, strong similarities in the HPLC immunograms across species suggests that steroid metabolism is relatively conserved among Lynx species. Gestagens were primarily excreted as polar conjugates or unknown metabolites, whereas estrogen metabolism revealed a huge proportion (approximately 50%) consisting of 17beta-estradiol and estrone. These results are consistent with patterns of steroid metabolism in other felid species. Only two minor species-specific patterns emerged. In bobcats, we observed an exceptionally high proportion of gestagen conjugates, and in Iberian lynx, there was an exceptionally high proportion of estrone. The comparison of HPLC immunograms within individuals revealed that intra-individual variations in steroid metabolite composition are considerably high. However, changes in metabolite composition did not correlate with specific reproductive stages; rather, they seemed to occur at random. We assume that these differences may reflect changes in liver metabolism and/or qualitative and quantitative variations in gut bacteria composition, resulting in differences in faecal metabolite composition.
随着粪便激素代谢物分析的日益普及，深入了解粪便代谢物组成的动态变化非常重要。本研究的目的是比较欧亚猞猁、伊比利亚猞猁、加拿大猞猁和短尾猫这四个猞猁物种的定量粪便孕烷和雌激素代谢物组成。比较高效液相色谱免疫图谱是从每个猞猁物种的个体雌性在怀孕前、怀孕中和怀孕后收集的粪便样本中生成的。孕烷和雌激素揭示了三种类似的免疫反应性粪便代谢物类别：（1）极性代谢物，可被酶水解，因此可被指定为共轭物，（2）非水解极性代谢物，和（3）非极性代谢物或游离甾体。对于这两种激素，物种间 HPLC 免疫图谱的强烈相似性表明甾体代谢在 Lynx 物种中相对保守。孕烷主要以极性共轭物或未知代谢物形式排泄，而雌激素代谢则揭示了大约 50%的 17β-雌二醇和雌酮。这些结果与其他猫科动物物种的类固醇代谢模式一致。仅出现了两种较小的物种特异性模式。在短尾猫中，我们观察到孕烷共轭物的比例异常高，而在伊比利亚猞猁中，雌酮的比例异常高。个体内 HPLC 免疫图谱的比较表明，类固醇代谢物组成的个体内变异相当高。然而，代谢物组成的变化与特定的生殖阶段无关；相反，它们似乎随机发生。我们假设这些差异可能反映了肝脏代谢的变化和/或肠道细菌组成的定性和定量变化，导致粪便代谢物组成的差异。
