云南省黄胸鼠体表恙螨地域分布分析

Geographical Distribution of Chigger Mites on Rattus flavipectus in Yunnan Province

目的探讨云南省不同地理区域黄胸鼠体表寄生恙螨差异。方法汇总2001-2012年来自云南省25个县(市)的现场调查资料,对云南省5个动物地理小区(横断山中部小区、横断山南部小区、滇东高原小区、滇西高原小区和滇南山地小区)中黄胸鼠体表恙螨的构成比(Dr)、染螨率(RM)、平均多度或螨指数(MA)、感染度(MI)、物种丰富度指数(S)和多样性指数(H′)等指标进行统计分析。运用系统聚类方法比较5个动物地理小区黄胸鼠体表恙螨群落之间的相似性。结果共捕获黄胸鼠2 118只,采集体表恙螨11 040只,分类鉴定为3亚科17属114种,总染螨率为19.6%(416/2 118),平均多度为5.2只螨/鼠,感染度为26.5只螨/鼠。不同动物地理小区的黄胸鼠体表恙螨的种类数、种类构成和优势螨种不一致,其中,滇南山地小区的恙螨感染率、平均多度和感染度最高,分别为28.9%(179/620)、10.6只螨/鼠和36.6只螨/鼠。黄胸鼠个体数量与恙螨种类数之间存在明显直线正相关关系(r=0.942,P<0.05)。地处低海拔地段的滇西高原小区和滇南山地小区的黄胸鼠体表恙螨群落相似性最高,主要优势螨种为地里纤恙螨(Leptotrombidium deliense);横断山中部小区、横断山南部小区和滇东高原小区主要优势螨种为印度囊棒恙螨(Ascoschoengastia indica)和舌盾棒六恙螨(Schoengastiella ligula)等。结论云南省黄胸鼠体表恙螨感染普遍,物种多样性高,不同地域的黄胸鼠体表恙螨构成差异较大。

Objective To investigate species composition of chigger mites on Rattus flavipectus in different zoo- geographical subregion of Yunnan Province. Methods The field investigation was carried out in 25 counties of Yunnan Province during 2001-2012. Some conventional statistical methods were adopted to calculate the species of collected chigger mites, constituent ratio （Dr）, mite infestation rate （RM）, mean abundance （MA）, mean intensity （MI）, species richness （S） and species diversity index （H＇） of chigger mites in five zoogeographical subregions. The hierarchical clus- ter analysis was used to compare the similarity of chigger mite communities on the rats in the subregions. Results A total of 2 118 R.flavipectus were captured. 11 040 individuals of chigger mites were identified as 3 subfamilies, 17 gen- era and 114 species. The overall RM, MA and MI of chigger mites were 19.6%（416/2 118）, 5.2 mites per examined rat and 26.5 mites per infested rat, respectively. The species richness, species composition and dominant species of chigger mites on R.flavipectus were not identical among the subregions. The RM（28.9%, 179/620）, MA （10.6） and /1,//（36.6） of chigger mites in the mountainous subregion of southern Yunnan were the highest among the five subregions. There was a significantly linear positive correlation between the number of R.flavipectus and the species of chigger mites （r=0.942, P〈 0.05）. The similarity of chigger mite communities between plateau subregion of western Yunnan and mountainous subre- gion of southern Yunnan was the highest, and the dominant species of chigger mites was Leptotrombidium deliense. The main dominant species of chigger mites in middle subregion and southern subregion of Hengduan Mountains, and eastern plateau subregion of Yunnan were Ascoschoengastia indica and Schoengastiella ligula. Conclusion The infestation of chigger mites on R. flavipectus is common with a high species diversity. The composition of chigger mite community in different geographical subregions is siginificantly different.