Abstract: Based on the results obtained by author et al.(1994) with principal component analysis (PCA) to 15 growth indices of brandt’s vole (Microtus brandti), the width between maxillary incisor and molar was decided as the index of age determination due to its objective and practical circumstance.After further analysis, the population of brandt’s vole was divided into five age groups of juvenile (width between maxillary incisor and molar under 6.49mm), subadult (6.50~7.33mm),adult Ⅰ (7.34~8.38mm),adult Ⅱ (8.39~9.43mm) and old age (over 9.44mm) by width between maxillary incisor and molar.This paper also analysed the age composition and its seasonal change and the relationship between age groups and reproduction.

Key words: Brandt’s vole, Age identification, Width between maxillary incisor and molar

摘要： 本文在笔者前期工作的基础上,根据布氏田鼠15项生长指标的主分量分析结果,筛选出以头骨上齿隙作为划分布氏田鼠相对年龄组客观而简便实用的指标。该鼠的头骨上齿隙没有性别差异,对雌雄鼠可采用同一标准同时划分其年龄组。通过进一步分析,将其划分为五个年龄组：幼年组的上齿隙在6.49mm以下,亚成年组为6.50～7.33mm,成年一组为7.34～838mm,成年二组为8.39～9.43mm,老年组在9.44mm以上。此外,本文尚就年龄组成及其季节变化、年龄与繁殖等方面进行了分析。

关键词: 布氏田鼠, 年龄鉴定, 上齿隙