BACKGROUND To avoid destructive sampling for conservation and genetic assessment, we isolated the DNA of clam Cyclina sinensis from their feces. DNA electrophoresis and PCR amplification were used to determine the quality of fecal DNA. And we analyzed the effects of different conditions on the degradation of feces and fecal DNA. RESULTS The clear fecal DNA bands were detected by electrophoresis, and PCR amplification using clam fecal DNA as template was effective and reliable, suggesting that clam feces can be used as an ideal material for noninvasive DNA isolation. In addition, by analyzing the effects of different environmental temperatures and soaking times on the degradation of feces and fecal DNA, we found that the optimum temperature was 4 °C. In 15 days, the feces maintained good texture, and the quality of fecal DNA was good. At 28 °C, the feces degraded in 5 days, and the quality of fecal DNA was poor. CONCLUSIONS The clam feces can be used as an ideal material for noninvasive DNA isolation. Moreover, the quality of fecal DNA is negatively correlated with environmental temperature and soaking time.

中文翻译：

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蛤Cyclina sinensis的粪便DNA分离和降解：用于保护和遗传评估的非侵入性DNA分离。

背景技术为了避免破坏性取样进行保存和遗传评估，我们从蛤仔Cyclina sinensis的粪便中分离了它们的DNA。DNA电泳和PCR扩增用于确定粪便DNA的质量。并且我们分析了不同条件对粪便和粪便DNA降解的影响。结果通过电泳检测到粪便DNA条带清晰，以蛤fe粪便DNA为模板进行PCR扩增是有效和可靠的，表明蛤ces粪便可作为无创DNA分离的理想材料。此外，通过分析不同环境温度和浸泡时间对粪便和粪便DNA降解的影响，我们发现最佳温度为4°C。15天后，粪便保持良好的质地，粪便DNA的质量良好。在28°C下，粪便在5天内降解，粪便DNA质量较差。结论蛤粪可作为无创DNA分离的理想材料。此外，粪便DNA的质量与环境温度和浸泡时间呈负相关。