锡金小家鼠种群年龄鉴定及繁殖变化规律

为制定锡金小家鼠年龄鉴定的体重划分标准,采用夹夜法调查,收集鼠类标本。对1984～2012年贵州省关岭、三都、大方3个县历年捕获的249只锡金小家鼠体重进行统计分析,结果表明:锡金小家鼠平均体重为(15.57±5.97)g,根据体重的频次分配特征,参照其繁殖状况,将其年龄划分为5个年龄组,制定了各年龄组的体重划分标准:幼年组(Ⅰ)体重≤8.0 g,亚成年组(Ⅱ)体重8.1～13.0 g,成年Ⅰ组(Ⅲ)体重13.1～18.0 g,成年Ⅱ组(Ⅳ)体重18.1～23.0 g,老年组(Ⅴ)体重>23.0 g。不同年龄组体重之间差异极显著,且随着种群年龄的增长而不断增加。不同年龄组种群繁殖力存在显著差异,参与种群繁殖的主要群体为成年Ⅰ组、成年Ⅱ组。种群年龄组成具有明显的季节变化。

Population Age Identification and Reproduction Fluctuation Law of Mus pahari

In order to establish boy weight division criterion for age identification of Mus pahari population,the samples of this mouse were collected and surveyed by using night trapping method.We did statistical analysis on the body weight of 249 heads of Mus pahari which were captured in Guanling county,Sandou county and Dafang county of Guizhou province from 1984 to 2012.The results indicated that the average body weight of these mice was(15.57 ± 5.97) g.According to the frequency distribution characteristics of body weight and the reproductive condition,they were divided into five age groups.We established the body weight division criterion for each age group: young group(Ⅰ) was less than 8.0 g,sub-adult group(Ⅱ) was 8.1 ～ 13.0 g,adult group Ⅰ(Ⅲ) was 13.1 ～18.0 g,adult group Ⅱ(Ⅳ) was 18.1 ～23.0 g,and old group(Ⅴ) was more than 23.0 g.There was a significant difference in body weight among different age groups.With the growth of population age,the body weight increased continuously.Furthermore,there was a significant difference in reproduction capacity among the different age groups.Adult group Ⅰ and adult group Ⅱ were the main reproductive contributors.Moreover,there was a significant seasonal variation in the population age structure.