塔里木兔年龄鉴定指标的研究

STUDIES ON THE AGE DETEKMINATION INDICES OF YARKAND HARE(LEPUS YARKANDENSIS)CHEN

本文对塔里木兔的体重、体长、颅全长、颧宽、门齿孔长、下颌骨长和晶体干重等７项生长指标进行了主分量分析，确定了各项指标在年龄鉴定价值上的排序，结果显示用颅全长（因子负荷量０．９８）鉴定塔里木兔的年龄比较合理。

In order to determine the ages of Yarkand Hare(Lepus yarkandensis), seven growth indices of the specimens were studied by using principal component analysis ,They werebody weight,head and body lengths, full skull length, zygomatic width,the length ofincisive foramen, mandibular length and the dry weight of eye lenses;On the first prin-cipal component axis(Z_1 ), the contribution rate of the male correlation matrix was 79.36%while the female one was 88. 97%。The analyzed indices arranged in order offactor load on the first principal component axis,showed the following findings:1.On the axis of Z_1 male and female full skull lengths had the greatest factorLoads。So,full skull length could reflect the growth best。2.The factor loads of the length of incisive foramen and mandibular length on Z_1were above 0.93.So both the lengths could be used as age indices。3.Although body weight and head and body lengths were convenient age indices,it was not easy to measure the head and body lengths accurately and the exact body weight would be affected when female hare were pregnant。 4.Dry weight of eye lenses was not a suitable age index for Yarkand Hare because of their small factor loads on Z_1 To sum up,the full skull length would be used as the age indicator for Yarkand Hare。Through further analysis,the population of Yarkand Hare could be divided intothree age groups:juvenile(full skull length was less than 69.00 mm),subadult(69.00 75. 50 mm)and adult groups(over 75. 50 mm)