Abstract: The ability to obtain sufficient nutrients and energy from the environment determines the survival and reproduction of animals. To clarify the digestive strategies of changing nutrient contents for sympatric rodents with different body sizes, the Mus caroli and Rattus losea were fed with three diets with varied nutrient content. On the 10th and 20th day, the food intake, fecal output, net food intake and apparent digestibility were determined using the food balance method. The results showed that there was no significant change in body weight between the three food groups of M. caroli and R. losea during experiments, indicating that they were able to adapt to changes in food quality. In M. caroli, the daily intake of high-protein group on the 10th day was no different from that of the normal group, but significantly higher than the high starch group; the fecal output of the high protein group was significantly higher than that of the high starch group and the normal group. The apparent digestibility of the high starch group and the normal group was significantly higher than that of the high protein group. On the 20th day, there was no difference in daily food intake among the three groups of animals; the daily fecal output in the high protein group was higher than that in the high starch group and the normal group. The Rattus losea showed only 10 days when the high starch group and the normal group had higher apparent digestibility than the high protein group. This study revealed that M. caroli and R. losea can be adapted to changes in the nutrient composition of the food through different feeding and digestion strategies, although the difference in body size are large between the two rodents.

Key words: Mus caroli, Rattus losea, Diet quality, Food intake, Digestibility

摘要： 动物从环境中获取足够营养和能量的能力决定着其生存和繁殖。为探讨同域分布不同体型的鼠类对不同营养成分食物的摄食消化对策，以三种不同营养成分食物分别饲喂卡氏小鼠和黄毛鼠，在第10天和20天，以食物平衡法测定日摄食量、日粪便量、净摄入量和表观消化率。结果发现，在整个驯化过程中，两种鼠的不同食物组间体重无显著差异，表明均能够适应食物营养的变化维持收支平衡。在驯化第10天时，高蛋白组卡氏小鼠的日摄食量显著高于高淀粉组，但两组与普通组均无差异；高蛋白组卡氏小鼠的日粪便量显著高于高淀粉组和普通组；而净摄入量无组间差异；高淀粉组和普通组的表观消化率显著高于高蛋白组。至第20天时，三组动物日摄食量无差异；高蛋白组的日粪便量高于高淀粉组和普通组。黄毛鼠仅在第10天时高淀粉组和普通组表观消化率高于高蛋白组，三组黄毛鼠其他消化参数在第10天和第20天均无显著组间差异。结果表明，体型不同的鼠类因消化冗余能力的差异，面对相同的食物营养成分变化，会以不同的摄食消化策略调节适应。

关键词: 卡氏小鼠, 黄毛鼠, 食物质量, 摄食, 消化