横断山区中缅树鼩肥满度的初步研究

Preliminary Study on Relative Fatness Intree Shrew(Tupaia Belangeri)in Hengduan Mountain Region

通过对分布于横断山区中缅树鼩的肥满度进行测定,探讨中缅树鼩肥满度与环境之间的关系.将56只体重相近的中缅树鼩随机分为7组(每组8只):对照组(自由取食,control);分别禁食12h(F12h)组、24h(F24h)组和36h(F36h)组;以及禁食36h后重喂食12h(R12h)组、48h(R48h)组和7d(R7d)组.实验结束后测定动物的体重和体长.采用体重与体长立方的比值(K=100 W/L3)作为测定肥满度的指标.结果发现:中缅树鼩雌雄个体肥满度之间差异不显著,不同年龄组之间肥满度差异不显著.中缅树鼩不同季节的肥满度差异极显著,肥满度的季节变化趋势为:冬季最高,秋季较高,春季较低,夏季最低.禁食和重喂食极显著影响中缅树鼩的肥满度,禁食后肥满度降低,禁食24h时达到极显著水平,禁食36h时最小,重喂食7d后能恢复到对照组水平.中缅树鼩肥满度在不同环境条件下的变化模式与其生存的食物波动大、高海拔低纬度和年平均温度较低的横断山区密切相关.

In order to study the relationship between body status and circumstances in tree shrew,relative fatness of tree shrew （Tupaia belangeri）was measured from Hengduan mountain region.56 tree shrews with similar body mass were used in our experiments which were divided into seven groups of eight individuals each group as follows：group 1 （control）：fed control tree shrew; group 2 （F12h）：fasted for 12 h; group 3 （F24h）：fasted for 24 h;group 4 （F36h）：fasted for 36 h; group 5 （R12h）：refed for 12 h following fasted for 36 h;group 6 （R48h）：refed for 48 h following fasted for 36 h;group 7 （R7d）：refed for 7 d following fasted for 36 h.At the end of experiment,we determined body mass and body size.The relative fatness of tree shrew was calculated by empirical formula （K=100 W/L3）.The results showed that there were no significant sexual differences of relative fatness in the tree shrew; the relative fatness showed no significant differences in the groups with different ages; but it had significant differences in different seasons,it was highest in winter and lowest in summer,then higher in autumn and lower in spring.Fasting and re-feeding had significant effects on relative fatness of tree shrew,fasting reduced relative fatness,and it reduced significantly after 24 h fasting,but it was can returned to the control level after re-feeding of 7 d.The changes pattern on relative fatness of tree shrew in different circumstances were related to their microenvironment,such as high elevation,low latitude,lower average ambient temperature and the big change of food resources in Hengduan mountain region.