Abstract: Food habit of small mammals is an important component in the study of population ecology. In this study, gastric contents and colon contents of 12 plateau pikas（Ochotona curzoniae）were tested through microhistological analysis in The Haibei Resrarch Station of Alpine Meadow Ecosystem under Chinese Academy of Sciences during July to June, 2018. The results showed that a total of 16 species（genus）of plants from 7 different families were identified in the gastric contents, including 15.07% of Elymus nutans, 9.07% of Oxytropis spp., 7.38% of Kobresia spp., 7.11% of Potentilla anserine. In contrast, only 6 species（genus）of plants from 3 different families were identified in the colon contents, including 21.99% Kobresia spp., 13.68% of Elymus nutans, 5.04% of Poa spp., 2.00% of Potentilla anserine. According to the microhistological results of contents of gastric and colon, through analyzing Simpson diversity index, Shannon-Wiener diversity index, Pielou evenness index and niche width index of the food composition of plateau pikas, it shows that Simpson diversity index, Shannon diversity index and niche width index were higher in gastric contents than in colon contents, however, Pielou evenness index was not. The recognizable rate in gastric contents was significant higher than in colon contents（χ ²=8.619，df=1，P<0.01）. The results indicated that the contents of gastric and colon observed in food habit were obviously different from each, the food preference indices were different, microhistological analysis of gastric contents can more accurately responds food composition and food selectivity of plateau pikas than colon contents.

Key words: Plateau pika, Microhistological analysis, Food habit, Contents of gastric and colon

摘要： 小哺乳动物的食性是种群生态学的重要组成部分。本研究于2018年6—7月，在中国科学院海北高寒草甸生态系统定位站地区，通过显微组织分析法对12只高原鼠兔（Ochotona curzoniae）胃及结肠内容物进行了食性比较分析。结果表明：高原鼠兔胃内容物镜检到7科16种（属）植物碎片，主要组分包括垂穗披碱草（Elymus nutans）15.07%、棘豆（Oxytropis spp.）9.07%、嵩草（Kobresia spp.）7.38%、鹅绒委陵菜（Potentilla anserine）7.11%；而结肠内容物只镜检到3科6种（属）植物碎片，主要组分包括嵩草21.99%、垂穗披碱草13.68%、早熟禾（Poa spp.）5.04%、鹅绒委陵菜2.00%。根据高原鼠兔的胃和结肠内容物镜检结果，分别计算其取食植物的Simpson指数、Shannon-Wiener指数、均匀度指数、食物生态位宽度指数，分析高原鼠兔食物组成多样性，结果显示，除了均匀度指数，其它3种指数胃内容物均高于结肠内容物，且胃内容物和结肠内容物的识别率差异极显著（χ²=8.619，df=1，P<0.01）。上述研究结果表明，食性分析中胃与结肠内容物镜检结果显著不同，所得出的食物选择结果也大相径庭，胃内容物显微分析较结肠能更准确地反映高原鼠兔采食的植物种类以及对食物的选择性。

关键词: 高原鼠兔, 显微组织分析, 食性, 胃与结肠内容物