关键词: 年龄鉴定, 黄胸鼠, 胴体重, 沧源县

Abstract: Objective To establish a standard system for Rattus tanezumi age divisions in Cangyuan county, Yunnan province, China, and to provide a scientific basis for monitoring and control of R. tanezumi. Methods Trap-at-night method was used during 2010-2011 to capture R. tanezumi in all farming areas of the county. The rats were then divided into different age groups based on nes weight. Results One hundred and ninety-nine rats were collected, 170 of which had an average nes weight of (62.65±2.26) g. According to the nes weight while taking into account the reproductive status and morphological characteristics, the rats were divided into five age groups. Division standards for each group were: infancy group (Ⅰ), nes weight ≤30.0 g; junior group (Ⅱ), nes weight 30.1-55.0 g; adultⅠ group (Ⅲ), nes weight 55.1-85.0 g; adultⅡgroup (Ⅳ), nes weight 85.1-115.0 g, and senior group (V), nes weight >115.0 g. T-test showed that the difference between the mean values of each two groups was of statistical significance (P<0.01), while the nes weight and body weight showed a positive correlation with statistical significance. Conclusion Nes weight method is simple, relatively precise and easy for grassroot-level surveillance on rodents. It can be recommended as a main method for age determination of R. tanezumi in the field.

Key words: Age determination, Rattus tanezumi, Nes weight, Cangyuan county