【摘要】 <正> 环境温度是哺乳动物分布的一个重要的限制因子。哺乳动物能否适应各种环境又取决于动物本身的代谢和体温调节的能力。所以研究哺乳动物的代谢和体温调节,对于了解它们适应各种环境的能力是十分重要的。啮齿动物是哺乳动物中种类最多、分布最广、与人类关系也比较密切的一类恒温动物,所以采用啮齿动物作为比较研究的对象。 近年来国外对啮齿动物的代谢和体温调节的研究,报道颇多,以居住类型而言而:穴居、挖洞型啮齿动物的代谢和体温调节的研究有分布在热带、温带的种类,也有分布在山区、平原、沙漠干旱地带的种类;地上活动型啮齿动物的这方面研究有分布在平原、山区、沙漠干旱地带、沿海和中湿地区的种类。而同一地区不同居住类型的比较研究报道较少。更多还原

【Abstract】 Three species of rodents were studied on metabolism and thermoregulation, They arc mandarin vole （Microtus mandarinus ） . fossorial! ratlike hamster （ Cricclu lus triton） , burrowing; buff-breasted rat （ Rattus flavipccius ） , above ground.Their body temperature （ T_b ）, oxygen consumption （ ml0₂/g.h ） and body weight （ W ） were measured at different ambient temperatures （ T_a ）, 5°,10°,20°,25°,30°, 35℃.The differences of oxygen consumption in the tiree spcies as due to the differences of their body weights were adjusted with the method analysis of covariance, and the mean minimum oxygen consumption of each species in resting slate was taken as the basal metabolic rate （ BMR ） : in mandarin vole, the BMR at an ambient temperature of 20℃, being 3.07 m10₂/g.h, and rat-like hamster and buff-breasted rat at 25℃, T_abeing 2.31 m10₂/g.h and 2.62 m10₂/g.h respectively.（ table 2 ）.The thermoneutral zone（TNZ）for M.mandarinus extends from 20℃ to 25℃ and for C.triton and R.flavipectus from 25℃ to 30℃.Below the lower critical temperature ( T_IC ), ml0₂/g.h increased with reducing T₂; above the upper critical te-mperalure(T_UC, m10₂/g.h increased with increasing T₄. The mean body temperature （ T ） . for M .mandarinus increased .1. 1 C at 30 C T_a, and for the other two spcci es increased 2.8℃ and 3.1℃ at 35℃ T_b respectively.Below thermoneutrality, the regression equations of metabolism on ambient temperature were calculated.In each species, when metabolic rate was zero, the curve of metabolism on ambient temperature acrossed with the axis of abscissae, and the point crossed was higher than the body temperature so the slope of the curve which included physical and chemical regulations did not represent thermal conductance （ C ） . Below thermoneutrality, the mean minimum thermal conductance （ Cm ） was calculated with the formula C = MR/（ T_b - T_a ） （Morrison & Ryser 1951） . Cm in M .mandarinus being 0.1956ml0₂/g.h.C: in C.lriton,0.1920ml0₂/g.h.c: and in R.fla-vipectus, 0.1667ml0₂/g.h.c.In our experiment, the fossorial form, has the lowest BMR: in the above ground form, BMR being the highest; while in the burrowing or semi-fossorial forms, BMR being intermediate. On the contrary, Cm in the fossorial form was the highest; in the above ground species, it was the lowest; where as in the semi-fossorial burrowing species, it: was medium.At T_a =5℃, all the three species were found to eroueh in the eage, and M. mandarinus and C.triton appeared to bite the wires of the cages. In hyperthermy C. iriton and R.flavipcctus rendered their pelages wet with saliva.Cm of the three species were found to approximate the values studied dy McNab （1979） . The BMR of M.mandarinus and C.triton were approximately equal to the value of fossorial forms as found by McXab （1979）; where as the BMR of R.fla-vipccius being higher than the value of non-1 ossorial species, which McNab （ 1979 ） showed.In the three species, the relationship of metabolism being thermal neutrality to the body weight and ambient temperature could be expressed with the following experiential formula: MR= （ 210 - 5.8T_a ） w-^0.88, which indicated evidently that MR was affected by the two factors （ T_a and W ） simultaneously.更多还原