Li Xing-Sheng, Wang De-Hua
State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Zhongguancun, Haidian Beijing, People's Republic of China.
J Comp Physiol B. 2005 Nov;175(8):593-600. doi: 10.1007/s00360-005-0022-2. Epub 2005 Sep 7.
Seasonal adjustments in body mass and thermogenesis are important for the survival of small mammals during acclimatization in the temperate zone. To determine the contributions of short photoperiod and cold temperatures to seasonal changes in thermogenesis and body mass in Mongolian gerbils (Meriones unguiculatus), body mass, basal metabolic rate (BMR), nonshivering thermogenesis (NST), energy intake and energy digestibility were determined in seasonally acclimatized and laboratory acclimated animals. Body mass showed significant seasonal changes and decreased to a minimum in winter. Both BMR and NST increased in winter, and these changes were mimicked by exposing animals to short photoperiod or cold temperatures in the animal house. Digestible energy intake also increased significantly in winter, and also during exposure of housed animals to both short photoperiod and cold. These results suggest that Mongolian gerbils overcome winter thermoregulatory challenges by increasing energy intake and thermogenesis, and decreasing body mass to reduce total energy requirements. Short photoperiod and cold can serve as effective environmental cues during seasonal acclimatization.
在温带地区适应环境的过程中，小型哺乳动物的体重和产热的季节性调节对其生存至关重要。为了确定短光照周期和低温对蒙古沙鼠（Meriones unguiculatus）产热和体重季节性变化的影响，我们测定了季节性适应和实验室适应动物的体重、基础代谢率（BMR）、非颤抖性产热（NST）、能量摄入和能量消化率。体重呈现出显著的季节性变化，在冬季降至最低。冬季BMR和NST均增加，将动物置于动物房的短光照周期或低温环境中也会出现类似变化。冬季可消化能量摄入量也显著增加，将圈养动物置于短光照周期和低温环境中时也是如此。这些结果表明，蒙古沙鼠通过增加能量摄入和产热、降低体重以减少总能量需求来应对冬季体温调节挑战。短光照周期和低温可作为季节性适应过程中的有效环境信号。
