微尾鼩种群繁殖的年龄和季节特征

REPRODUCTION OF ANOUROSOREX SQUAMIPES POPULATIONS IN DIFFERENT AGES AND SEASONS

2003年9月～2004年8月对四川南充地区微尾鼩种群不同年龄组繁殖的差异以及各年龄组在不同季节的差异进行研究.结果表明,微尾鼩总性比为1.05,经χ2检验,两性差异不显著,繁殖个体性比为1.08,两性差异不显著.雄性微尾鼩1、2月份各年龄组的睾丸大小(长径与短径)和重量差异不显著,3～12月份差异极显著.微尾鼩各年龄组睾丸大小和重量在12mo内季节变化为1、2月差异均不明显,3～12月份未成体组(Ⅰ)季节变化明显,而成体Ⅰ组(Ⅱ)和成体Ⅱ组(Ⅲ)差异不明显.雌性子宫斑数在1～10之间,平均胎仔数为4.05±0.14只(N=76),4、9月份为繁殖高峰期,繁殖指数分别为2.37和1.45,4～10月份成体Ⅰ组(Ⅱ)和成体Ⅱ组(Ⅲ)的繁殖力和平均胎仔数年龄差异不明显,成体Ⅱ组(Ⅲ)繁殖力和平均胎仔数在4～12月份季节变化不显著.1、2月份均为雌雄微尾鼩非繁殖期,3～12月份为繁殖期.

The study on the reproduction differences in different ages and seasons of wild Anourosorex squamipes populations was made from September, 2003 to August, 2004 in Nanchong, Sichuan. The results showed that the sex ratios of wild populations and reproductive populations of A. squampies were 1.05 and 1.08 （ ♀/ ♂） respectively, and there was no significant difference between male and female ones. The sizes and weights of testicles among the three age groups were not significantly different from January to February in 2004, but greatly differed during the rest ten months. The seasonal variations of testicles size and weight among the three age groups were insignificantly different between January and February; the seasonal variations of age group Ⅰ from September to December in 2003 and from March to August in 2004 were significantly diffenrent, but insignificantly during the rest two months and between age group Ⅱ and age group m. In main breeding seasons, the mean litter size was 4.05 ＋ 0. 14 （ N = 76） and the numbers of womb spots were from one to ten. The reproduction ability reached the highest point in April and September with the reproductive index as 2.37 and 1.45, respectively. The mean litter sizes and reproduction between age group Ⅱ and age groupⅢ were insignificantly different from April to October, and the seasonal variation of mean litter sizes and reproductive ability of age group m were insignificantly different. From January to February A. squamp- ies could reproduce but not in the rest ten months. Tab 2, Ref 24