光周期驯化对树麻雀性腺重量和基础能耗的影响

Effects of Basal Energy Expenditure and Gonad Tissue Masses of Tree Sparrows in Photoperiod Acclimation

为探讨光周期对麻雀基础能耗和性腺重量的影响,对25℃和3种不同光周期的麻雀进行4周人工气候箱驯化后,分别比较了雌、雄麻雀的体重、个体BMR和性腺的鲜重和干重。结果显示,光周期作为繁殖的信号对麻雀性腺重量有极显著的影响。雄麻雀的体重、个体基础能耗和性腺重量的变化幅度比雌麻雀显著,繁殖初期的雄麻雀很可能要早于雌麻雀进入繁殖状态;随光周期的延长和性腺重量的增加,麻雀个体的基础能耗呈现递减趋势。总之,较低的生存压力和个体基础能耗的降低是麻雀繁殖的基础和前提。繁殖初期麻雀拥有相对较低的体重和个体BMR,这是麻雀个体的生存、繁殖与生存压力之间能量预算的结果,也是生存能耗和繁殖能耗与个体适合度之间进行能量预算的结果。

In order to investigate the light cycle on the basal energy expenditure of tree sparrows and the effects of gonadal weight, we domesticated tree sparrows with at a temperature of 25℃, under three photoperiods in a climate box for four weeks, and then measured their body weights, basal metabolic rates （BMR）, as well as the gonadal organ＇s fresh and dry weights. The results showed that photoperiod is the length of the signal propagation caused by the sparrow, and affects the weight of the gonadal organ very significantly. The changes in the male sparrow＇s body weight and BMR and gonadal weight were more significant than that of female, and it entered reproductive status earlier. The basal energy expenditure of tree sparrows may decrease with photoperiod extension and gonadal organ＇s masses increase. We concluded that the lower survival pressure and BMR was the basis and the key for tree sparrow breeding. Tree sparrows in early breeding seasom have a relatively low body weight and individual BMR, which is the result of energy estimates neeeded for survival and reproduction and survival pressures, and also is the result of the energy budget among the survival and reproduction of power consumption and individual fitness.