褐家鼠对捕食者气味的行为和生理响应

The coevolution between the prey and predator is one of the most interesting topics that have been studied by many zoologists and ecologists up to now. The odors of the predators play an important role in the evolution of the prey. But it is debatable what the mechanism by which prey recognizes predator odors is and thereby how the prey trades off the predation risk in the environment. By using the ethological, physiological and molecular methods, this project is to investigate the influence of the odors of different species on the behavioral, hormonal, and molecular levels of the stress genes and the nerves of brain region for three strains of Norway rat which have same genetic background and different experience to odors (field Norway rat, first generation of laboratory bred Norway rat and Wistar rat), to determine the role of genetics and environmental factors in recognizing the odors of the predators for Norway rats, further to analyze the difference and effectiveness of the odors of the different predators, and finally to discuss the underlying mechanism by which Norway rat recognize the odors of the different predators from the perspective of behavior, physiology and genetic. The project also investigates the changes of behavior, hormone, and level of the stress genes in different brain region for the three kinds of Norway rat under the conditions of different exposure concentration, time and type of the odors of the same predator, determines the ability of the Norway rat trading off the predation risk through the odors of the predators, discusses its adaptation strategy. From above, the project will supply the foundational data for understanding the coevolution between the prey and predator and produce the new methods and ideas for controlling the damage of the Norway rat.

捕食者与猎物之间的协同进化一直是动物学家和生态学家研究的热点问题之一，而捕食者气味在猎物的进化过程中有重要作用。然而，猎物对捕食者气味的识别机制及其如何藉此权衡环境中的捕食风险尚无定论。本项目采用行为学、生理学和分子生物学的方法：研究不同物种气味对遗传背景相同、而生活环境和经历不同的三种类型褐家鼠的行为、激素水平、应激基因表达量以及脑神经环路的影响，确定遗传和环境因素在褐家鼠识别捕食者气味中的作用，分析不同捕食者气味源所产生的差异及有效性，从行为-生理-基因三个层次探讨褐家鼠对捕食者气味的识别机制和反应对策；研究三种类型褐家鼠在同种捕食者气味浓度、暴露时间及暴露方式不同时的行为、激素水平、应激基因表达量和脑神经环路的变化，确定褐家鼠通过气味权衡环境中捕食风险大小的反应能力，探讨褐家鼠对捕食者气味的适应对策，为揭示捕食者与猎物之间的协同进化提供理论依据，为褐家鼠的危害防治提供新的思路和方法。

本项目确定了兔、狗獾、猫以及黄鼬气味对野生褐家鼠、室内繁殖褐家鼠和Wistar大鼠的行为、激素水平、应激基因表达量的影响，探讨了褐家鼠对捕食者气味的识别机制和反应对策；测定了气味作用时间对褐家鼠行为、激素、应激基因和脑神经环路的影响，探讨了褐家鼠对捕食者气味的适应对策。项目按计划完成研究内容，完成研究目标。主要研究结果如下：. 在兔气味和天敌动物气味条件下，野生褐家鼠和室内繁殖褐家鼠的防御行为明显增加，非防御行为显著降低；Wistar大鼠对每种气味均具有明显的反应。三种类型褐家鼠的ACTH和Cort水平以及下丘脑c-fos mRNA表达量在兔气味组与对照组之间均没有显著差异，而三种天敌动物气味组与对照组之间均存在显著差异。说明褐家鼠能够识别不同物种气味，Wistar大鼠对外界环境变化较为敏感。. 短期猫气味暴露使室内繁殖褐家鼠和Wistar大鼠的防御行为显著高于对照组个体，非防御行为显著低于对照组个体，随着暴露时间的延长，这些行为又恢复到与对照组无显著差异的水平；同时，它们的应激激素ACTH、CORT的浓度以及下丘脑c-fos mRNA的表达量和四个脑区AHP、VMHC、MeAD、BLA中的Fos活性显著与对照组相比均显著增加，随着暴露时间的延长，也恢复到与对照组无显著差异的水平。说明褐家鼠对天敌动物的气味具有一定的适应性，并从行为和生理上做出响应。. 短期猫气味暴露后，褐家鼠与对照组杏仁核中的差异蛋白有14个，Wistar大鼠与对照组杏仁核中的差异蛋白有17个；长期猫气味暴露后，褐家鼠与对照组杏仁核中的差异蛋白有26个，Wistar大鼠与对照组杏仁核中的差异蛋白有33个，这些蛋白与能量代谢、转录、信号传导、疾病防御、泛素-蛋白酶体途径生物功能相关。. 项目完成期间，申请者以通讯作者发表论文7篇。6篇为SCI收录，1篇为中文CSDS文章。. 项目完成过程中，有4名硕士生和1名博士生参加工作。