蜂桶寨自然保护区中华姬鼠和社鼠食性的季节变化及与肠道长度的关系

Diet composition of Apodemus draco and Niviventer confucianus in Fengtongzhai Nature Reserve,China and its effects on their intestinal lengths

为揭示啮齿动物食性及其对消化道肠道长度的影响,我们于2008年在四川省宝兴县蜂桶寨国家级自然保护区内以中华姬鼠和社鼠为对象展开了研究。结果发现社鼠和中华姬鼠均以摄食种子为主,食谱中各食物成分在性别之间无显著差异,但季节变化明显。在各食物成分中,摄入种子百分比与中华姬鼠及社鼠小肠长之间呈显著正相关,而昆虫成分则相反。分析认为,中华姬鼠和社鼠取食食物成分的季节变化,可能与不同季节中食物资源可获得性的不同有关,消化道长度的变化可能体现了对季节性食物资源和能量需求的适应。

We conducted a field survey on the sympatric Apodemus draco and Niviventer confucianus in 2008 in Fengtongzhai Nature Reserve, China to examine the annual diet composition of small rodents and its effects on their intestinal lengths. The results indicated that, for both rodents, seed was the primary component on their annual diet, and that their diet composition varied significantly across seasons. Of the four categories of diet components, percent of seed ingested had a significant positive influence upon the length of the small intestine, and the influence of the remaining diet components varied depending on the species. We believe that the difference of diet composition for the two species across seasons was likely related to the availability of food resource in the reserve, and the change of digestive tract length perhaps play an important role in the adaptation to seasonal energy demand and food resources. Therefore, possible interspecific difference should be considered when investigating physiological strategies adaptive to different types of food resources for different species in future research.