黔中地区小家鼠种群繁殖特征

Study on population reproduction of Mus musculus in Qianzhong areas

为了摸清小家鼠种群繁殖特征在黔中地区的变动规律，为种群数量预测预报提供依据。通过对1990～2002年贵州省息烽县小家鼠种群繁殖特征分析，共解剖标本1679只，其中，雌鼠885只，雄鼠794只，结果表明：小家鼠在当地全年均可繁殖。主要繁殖期在2～11月，每年3—4月和9—10月为妊娠高峰期。种群性比为1．11，平均怀孕率35．79％±6．03％，平均胎仔数为4．67±1．25只，平均繁殖指数为0．86±0．17，平均睾丸下降率为73．88％±8．83％。不同年龄组之间种群繁殖力存在显著差异。随着种群年龄的增长繁殖力不断增加。同时比较了全国各地小家鼠种群繁殖特征的变化情况，胎仔数具有随纬度的升高趋向增多的特征。

1679 samples （885 males and 794 females） of Mus musculus were dissected to investigate the population reproduction characteristic during 1990 - 2002 in Xifeng county for forecasting the population quantity in the future. The results indicate that Mus musculus can reproduce in Xifeng county all the year round, the main reproduction season is between February and November and the peak pregnancy durations are between March and May and between September and October. The mean pregnancy rate,foetus number,reproductive index and descent rate of testis are 35.79 % ± 6.03 % ,4.67 ± 1.25, 0. 86 ± 0. 17 and 73.88 % ± 8.83 % ,respectively. There is a significant difference in the reproductive efficency among different age groups and the reproductive efficency gradually increases with the increase of population age. The foetus number increases with increase of latitude too.