多代驯化对布氏田鼠非繁殖期性激素本底水平的影响

为阐明驯化过程对季节性繁殖的布氏田鼠Lasiopodomys brandtii性腺活性的影响，采用放射免疫技术从秋季（11月）至翌年春季（3月）对室内驯化1月、3年和10年的雌雄鼠粪便中的性激素水平进行监测。结果显示，在11—12月非繁殖季节，驯化10年组雄鼠睾酮水平分别达到3年组和1月组的3.5倍和13.3倍，驯化10年组雌鼠雌二醇水平分别达到3年组和1月组的2.0倍和3.7倍，且差异均达到显著水平；长期（3年和10年）驯化组雄鼠在繁殖初期（1—3月）的睾酮水平也较短期驯化组显示出更大幅度的提升。表明在经历长期驯化后布氏田鼠对稳定的室内环境逐渐适应，非繁殖期性腺活性抑制的程度逐渐减弱，呈现出随驯化时长增加而逐渐递增的趋势，从而导致鼠类繁殖表型发生了可塑性变化。

Effects of multigenerational domestication on the baseline of gonadal hormones in Brandt's vole Lasiopodomys brandtii in the non-breeding season

To clarify the impacts of the domestication process on the reproductive activity of Brandt''s vole Lasiopodomys brandtii, the change of gonadal hormone levels in feces among lineages with different durations (1-month, 3-year, and 10-year, respectively) of domestication from autumn (November) to the following spring (March) were detected and compared with using radioimmunoassay. The results showed that 10-year domesticated male voles displayed 3.5 and 13.3 times higher testosterone levels than 3-year and 1-month groups, respectively. Similarly, 10-year domesticated female voles also displayed 2.0 and 3.7 times higher estradiol levels than 3-year and 1-month groups, respectively. Moreover, the increase of testosterone levels was higher in the two long-term domesticated groups than that in 1-month group during initial mating period (January-March). These results indicated that the inhibition of gonadal activity in the non-breeding season was attenuated along with the prolongation of domestication and gradual adaption to the stable housing conditions, which led to the change in the plasticity of reproductive phenotype.