Abstract: 【Objective】 This study was aimed to investigate the ectoparasite infection of Myotis chinensis (M.chinensis) in Yunnan province, to analyze the factors affecting ectoparasite infection of M.chinensis in Yunnan province, and to provide a scientific basis for the prevention and control of related vector-borne zoonoses.【Method】 The M.chinensis were captured at three sampling sites in Yunnan province between July 2021 and August 2022, and its surface parasites were collected and identified based on identification data.The χ² test (Chi-square Test), independent-samples t-test, linear correlation, and SPSS 26.0 software were used to statistically analyze the infection status of ectoparasite infections in M.chinensis.【Result】 Of the 53 M.chinensis captured, 49 were infected with ectoparasites, with a high rate of ectoparasite infection (92.45%).All 2 841 ectoparasites collected from the surface of M.chinensis belonged to the Gamasina and Nycteribiidae, with S.myoti, S.kolenatii and M.zhijinensis as the dominant species.The mean abundance (t=-4.566, P<0.01) and mean intensity (t=-4.58, P<0.01) of parasite infections were extremely significantly higher in females than in males, while there was no correlation between body size (forearm length and body weight) and mean abundance of parasites.【Conclusion】 The prevalence of ectoparasite infections in M.chinensis in Yunnan province was high, and there were differences in ectoparasite infection between the sexes of M.chinensis, with a sex-bias.There was no significant correlation between the body size of M.chinensis and the mean frequency of ectoparasite infection.The experimental results would fill in the scarce research on bat ectoparasites in China and provide important theoretical guidance for the prevention of certain vector-borne zoonoses.

Key words: Myotis chinensis; ectoparasite; gamasid mite; bat fly; zoonoses