Advantages of using fecal samples for stable isotope analysis in bats: evidence from a triple isotopic experiment.
Advantages of using fecal samples for stable isotope analysis in bats: evidence from a triple isotopic experiment.
复制标题
使用蝙蝠粪便样本进行稳定同位素分析的优点：来自三重同位素实验的证据。
DOI：
--
复制
发表时间：
2013
影响因子：
2
通讯作者：
K. Koselj
中科院分区：
文献类型：
--
作者：
Ioanna Salvarina;E. Yohannes;B. M. Siemers;K. Koselj
理由
生态学研究中的稳定同位素分析通常是在需要捕获动物的生物材料（例如肌肉和血液）上进行的。粪便很少用于稳定同位素分析，尽管有可能进行非侵入性取样，并对饮食变化作出短期反应。由于缺乏校准实验和未知的饲料-粪便同位素差异（Δ（饲料-粪便）），这种有前途的方法被忽视。
方法
为了填补这一空白，我们模拟了自然界中发生的营养变化，当动物切换觅食栖息地时，例如从淡水到陆地系统，从耕地到森林或改变与海洋环境的距离。在一项对照实验中，两种蝙蝠（鼠耳蝠，菊头蝠ferrumequinum）的饮食被改变为同位素不同的。我们测量了粪便中稳定的氮、碳和很少使用的硫同位素，并计算了Δ（饮食-粪便）值。
结果
粪便在食物摄入后2-3小时内获得新的饮食特征;因此，它们适合于检测最近和快速的饮食变化。不同种属或饲料之间的Δ（饲料-粪便）（Δ）无差异（总平均值±标准差（sd））：Δ（15）N：1.47 ± 1.51‰，Δ（13）C：-0.11 ± 0.80‰，Δ（34）S：0.74 ± 1.10‰。M只有Δ（15）N。鼠耳蝠与零显著不同，并且在实验的天数中仅Δ（13）C不同。
结论
粪便稳定同位素现在可以进一步应用于哺乳动物生态学。这包括一系列的应用，如在短时间尺度上研究营养水平、资源或生境利用的变化。这种资料对于监测受人类活动影响而迅速变化的生态系统越来越重要。
RATIONALE
Stable isotope analysis in ecological studies is usually conducted on biomaterials, e.g. muscle and blood, that require catching the animals. Feces are rarely used for stable isotope analysis, despite the possibility of non-invasive sampling and short-term responsiveness to dietary changes. This promising method is neglected due to a lack of calibration experiments and unknown diet-feces isotopic difference (Δ(diet-feces)).
METHODS
To fill this gap, we simulated trophic changes occurring in nature when animals switch feeding habitats, e.g. by moving from freshwater to terrestrial systems, from cultivated areas to forests or changing distance from marine environments. In a controlled experiment, the diet of two bat species (Myotis myotis, Rhinolophus ferrumequinum) was altered to an isotopically distinct one. We measured stable nitrogen, carbon and the rarely used sulfur isotope in feces, and calculated Δ(diet-feces) values.
RESULTS
The feces acquired the new dietary signature within 2-3 h from food ingestion; thus, they are suited for detecting recent and rapid dietary changes. The Δ(diet-feces) (Δ) did not differ between species or diet (overall means ± standard deviation (sd)): Δ(15)N: 1.47 ± 1.51‰, Δ(13)C: -0.11 ± 0.80‰, Δ(34)S: 0.74 ± 1.10‰. Only Δ(15)N for M. myotis was significantly different from zero and only Δ(13) C differed among the days of the experiment.
CONCLUSIONS
Fecal stable isotopes can be now further applied in mammalian ecology. This includes a range of applications, such as studying changes in trophic level, resource or habitat use, on a short time-scale. Such information is gaining importance for monitoring rapidly changing ecosystems under anthropogenic influence.