布氏田鼠体温调节能力的胎后发育  

Postnatal development of thermoregulation in Brandt’s voles Lasiopodomys brandtii

作　　者：迟庆生[1] 王德华[1] 

机构地区：[1]中国科学院动物研究所农业虫害鼠害综合治理研究国家重点实验室

出　　处：《动物学报》2005年第5期780-789,共10页ACTA ZOOLOGICA SINICA

基　　金：国家自然科学基金(No.30430140;No.30170151);中国科学院知识创新工程项目(No.KSCX2-SW-103)~~

摘　　要：为探讨布氏田鼠幼体体温调节能力的发育特点,我们对其胎后发育过程中代谢产热和体温的变化进行了观察。测定记录了1-40日龄的布氏田鼠幼体在巢中的体温,在23℃和30℃条件下的静止代谢率,以及在23℃和30℃时暴露1·5-2h后体温的变化,计算了幼体的总热传导率和恒温指数,并测定了聚群对幼体代谢产热的影响。布氏田鼠是典型的晚成型发育类型,幼体出生时身体裸露,体温调节能力很差。17日龄前,幼体在23℃冷暴露1·5-2h不能维持恒定的体温,9-17日龄幼体的恒温能力发育迅速,17日龄后幼体在23℃时开始表现出有效的恒温能力。幼体发育过程中逐渐升高的恒温指数和逐渐下降的总热传导率,也反映了幼体不断增强的恒温能力。虽然幼体在发育早期恒温能力差,表现出变温性的特点,但代谢率的测定表明,即使刚出生的幼体也具有受到冷刺激而增加产热的反应。聚群实验结果表明,幼体的聚群行为在降低代谢率、节约能量方面有明显的作用。巢中幼体体温的测定表明,1-40日龄幼体体温逐渐升高的趋势明显,且始终保持在33℃以上。这些结果说明,布氏田鼠的幼体在生长发育过程中,主要靠细致的母体关怀、聚群行为、巢的保温作用以及自身较弱的产热能力来使体温维持在较高的水平,从而不会因体温过低而使幼体的生长速度降低[动物学报51(5):780-789,2005]。To understand the characteristics of postnatal development of thermoregulation in Brandt＇s voles, the whole developmental story was followed from the birth to 45 days old. Infant body temperatures were measured from the age of day 1 to day 40 immediately after removing the animals from the nest. The resting metabolic rate （RMR） of young voles at 23℃ and 30℃ were measured from day 1 to day 45 using an open circuit respirometry system. Body temperatures were measured before and after the exposure to ambient temperature of 23℃ and 30℃ for 1.5 - 2 hours during the postnatal development. The homeothermy index and total thermal conductance were also calculated. The effects of huddling on the RMR were investigated. The neonates of Brandt＇s voles are typical altricial, born naked with very poor thermoregulatory ability when isolated. Before day 17, voles cannot maintain a constant high body temperature after solitarily exposed to 23℃ for 1.5- 2 hours. From day 9 to day 17, the voles increased their thermoregulatory ability rapidly. Young voles started to thermoregulate efficiently on day 17 when the homeothermy index is about 0.97 and no significant difference between body temperatures before and after 23℃ exposure. Although vole pups show characters of poikilotherms during their early lives, the results of RMR measurements indicated that even the newborns can respond to cold by increasing thermogenesis. Huddling among vole pups can decrease their RMR significantly. Although Brandt＇ s vole pups are relatively weak in heat production and poor in insulation, careful parental care and huddling in the nest can prevent heat loss, thus they can maintain body temperatures at a relatively high constant level （above 33℃ ） even on day 1, and this can further increase the growth rate [Acta Zoologica Sinica 51 （5） ： 780 - 789, 2005].

关 键 词：布氏田鼠 体温调节 发育 聚群 晚成型 恒温指数 总热传导率 

分 类 号：Q413[生物学—生理学]