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Environmental cues,as temperature and photoperiod,play an important role in the seasonal regulation of an animals physiology and behavior.In this study,we performed a series of experiment (temperature,photoperiod,temperature×photoperiod) in which Tupaia belangeri was acclimated to different experimental design,as cold acclimation (cold: 5± 1℃),8 light: 16darkness; control: 25±1 ℃,8 light: 16darkness); short photoperiod (SD: 8 light: 16darkness,5±1 ℃) and long photoperiod (LD: 16 light: 8darkness,5± 1 ℃) acclimation; photoperiods (long photoperiod,16L:8D; short photoperiod,8L:16D) and temperatures (warm:30±1℃; cold: 5± 1℃) to test the hypothesis that photoperiod,temperature,or both together can trigger changes in serum leptin level,body mass,thermogenesis,and energy intake.The results shown as follow: 1).Mean core body temperature in cold acclimation animals decreased by 1.13 ℃ compared with controls.Thermogenic capacity,represented by resting metabolic rate and nonshivering thermogenesis increased in cold acclimated tree shrews from initial values of 1.58±0.12 and 2.48±0.10 to 2.76±0.11 and 3.01±0.14 mlO2 g-1 h-1,respectively,and the contribution of NSTmax in the tree shrews was decreased by 20.5% and showed a significant difference with the control group.After cold acclimation,tree shrews increased body mass by nearly 9.41 g compared to the control,the increase in body mass was mainly due to the growth of the digestive organs.This increase corresponded with adaptive adjustments in morphology of digestive tracts with 3.49 g increases in wet mass; Serum leptin levels decreased by 42.37%,and food intake significantly increased by 34.58%,in cold acclimated tree shrews; Uncoupling protein 1 (UCP1) content in brown adipose tissue (BAT) significantly increased by 50.38%.2).At the end,these shrews (SD) had a significant higher body mass,higher levels of energy intake,higher levels of cytochrome C oxidase (COX) activity and mitochondrial uncoupling protein-1 (UCP1) contents in brown adipose tissues (BAT),and higher concentrations of serum tri-iodothyronine (T3),lower thyroxine (T4) compared to LD shrews,but there was not significant in serum leptin and melatonin in the two group.Together,these data suggest tree shrews employ a strategy of maximizing body growth and increasing energy intake in response to cues associated with short photoperiod.3).Temperature was the more important environmental factor for variations of thermogenesis in T.belangeri,it showed body mass,RMR and NST were significantly increased in both cold and short photoperiod.The low temperature could induce an increase mitochondrial protein contents,cytochrome C oxidase (COX) activity of mitochondria and a-glycerophosphate oxidase (a-PGO) of Liver/BAT.But there were no significant differences in protein contents,COX and a-PGO under different photoperiods.Cold temperature could induce an increase of UCP1 in BAT,but showed no significant differences under different photoperiods.It seemed that T.belangeri were more sensitive to temperature.Further,serum leptin was involved in the processes of thermogenesis and body mass regulation in T.belangeri.Conclusion: Cold temperature and photoperiod have a significant effect on the thermoregulation of T.belangeri.Low temperature was more important in thermogenesis than short photoperiod.The short photoperiod affected the adaptive thermogenesis by increasing the activity of T45-DII in BAT.The temperature is the most important limit factor under T.belangeri transmitted towards northern,the liver plays a key role of the adaptive thermogenesis in this process.