McCue Marshall D
Department of Desert Ecology, Blaustein Institutes for Desert Research, Ben Gurion University of the Negev, Sde Boqer, 84990, Israel.
Comp Biochem Physiol A Mol Integr Physiol. 2008 Oct;151(2):239-46. doi: 10.1016/j.cbpa.2008.06.034. Epub 2008 Jul 5.
Fasting-induced changes in fatty acid composition have been reported to occur within the body lipids of several types of animals; however, little is known about the changes in fatty acid profiles exhibited by reptiles subjected to prolonged fasting. This study characterizes the fatty acid profiles of six reptile species subjected to sublethal periods of fasting lasting 0, 56, 112, and 168 days. Analyses of fatty acid methyl esters (FAMEs) conducted on the total body lipids of rattlesnakes (Crotalus atrox), ratsnakes (Elaphe obsoleta), pythons (Python regius), boas (Boa constrictor), true vipers (Bitis gabonica), and monitor lizards (Varanus exanthematicus) revealed that all of the species exhibited similar characteristic changes in their fatty acid profiles during starvation stress. According to ANOVAs, the four most effective indicators of the onset of starvation were significant increases in the [1] fatty acid unsaturation index as well as ratios of [2] linoleic to palmitoleic acid, [3] oleic to palmitic, and [4] arachidonic to total fatty acid concentrations. The results of this study suggest that FAME analyses might be useful for identifying nutritional stress and/or starvation among squamate reptiles; however, forthcoming studies will be required to validate the generality of these responses. I also review the potential limitations of this approach, and suggest experiments that will be important for future applications of FAME analyses. Ultimately, it is hoped that FAME analyses can be used in conjunction with current practices as an additional tool to characterize the prevalence of starvation experienced by free-living reptiles.
据报道，禁食引起的脂肪酸组成变化发生在几种动物的体内脂质中；然而，对于长期禁食的爬行动物所表现出的脂肪酸谱变化却知之甚少。本研究对六种爬行动物在持续0、56、112和168天的亚致死禁食期后的脂肪酸谱进行了表征。对响尾蛇（Crotalus atrox）、鼠蛇（Elaphe obsoleta）、蟒蛇（Python regius）、蚺蛇（Boa constrictor）、真蝰蛇（Bitis gabonica）和巨蜥（Varanus exanthematicus）的全身脂质进行脂肪酸甲酯（FAME）分析后发现，所有物种在饥饿应激期间其脂肪酸谱均表现出相似的特征变化。根据方差分析，饥饿开始的四个最有效的指标是[1]脂肪酸不饱和指数以及[2]亚油酸与棕榈油酸的比率、[3]油酸与棕榈酸的比率和[4]花生四烯酸与总脂肪酸浓度的显著增加。本研究结果表明，FAME分析可能有助于识别有鳞目爬行动物中的营养应激和/或饥饿情况；然而，需要进一步的研究来验证这些反应的普遍性。我还回顾了这种方法的潜在局限性，并提出了一些对FAME分析未来应用很重要的实验。最终，希望FAME分析能够与当前的做法结合使用，作为一种额外的工具来表征自由生活的爬行动物所经历的饥饿流行情况。
