Abstract:

Objective: To investigate the rodents species, density, and pathogens they carry in Zunyi, Guizhou Province, China. Methods: A total of 70 sampling points were set in 14 counties/districts of Zunyi, with five points in the east, south, west, north, and center of each county/district. Small mammals were monitored through night trapping in Zunyi from October 2021 to October 2022, followed by species identification and pathogen detection. Excel 2021 was used for data organization. SPSS 26.0 was used to analyze the density, species, and pathogen-carrying status of small mammals through rate or constituent ratio comparison with the Chi-square test (P < 0.05 indicates a statistically significant difference). Results: A total of 9 969 effective traps were placed at all the surveillance points, capturing 549 small mammals in total, of which 522 were rodents. The total density of small mammals was 5.51%. The total density of rodents was 5.24%. The rodent density was highest in Honghuagang District (12.94%), followed by Fenggang County (12.34%), and lowest in Chishui City (1.80%). There was a statistical difference in rodent density between the counties/districts (χ²=195.619, P < 0.001). Rattus norvegicus was the dominant rodent species in urban residential areas, rural residential areas, and key industries, while Apodemus agrarius was the dominant species in farming areas. The composition of rodent species statistically differed in different regions (the center, north, east, and west) of Zunyi (χ²=117.357, P < 0.001). Each small mammal was examined for Leptospira interrogans and Orientia tsutsugamushi in the liver, spleen, and kidney; Dabie bandavirus in the liver, spleen, and lung; and Hantavirus in the lung. Among 343 samples tested, 27 were positive, all for L. interrogans, with a pathogen detection rate of 7.87%. Shrews had the highest detection rate (16.00%), followed by A. agrarius (12.35%), and R. norvegicus had the lowest detection rate (1.64%). There was a significant difference in the detection rates of different species of small mammals (χ²=14.372, P=0.002). The detection rate was 9.66% (26/269) in farming areas, which was highest, and 2.94% (1/34) in key industries, with negative detection results in urban and rural residential areas. There were no differences in detection rates between different habitats (χ²=5.171, P=0.160). The detection rate was 27.03% in Meitan County, followed by 25.00% in Suiyang County, and zero in Renhuai City, Fenggang County, and Yuqing County, with a statistical difference between different counties/cities/districts (χ²=35.409, P=0.001). Conclusions: The density of rodents was relatively high in Zunyi. The detection of L. interrogans should be a warning of the possibility of related diseases. Local authorities should strengthen rodent control in spring and autumn and take comprehensive control measures according to actual situation and dominant rodent species and pathogen detection status in different habitats, so as to reduce the density of rodents and prevent the occurrence of rodent-borne diseases.

Key words: Rodent surveillance, Rodent density, Small mammal, Species composition, Pathogen

摘要：

目的: 了解遵义市鼠种类、密度及其携带病原体情况。方法: 设置遵义市14个县（市、区）为监测点，各县（市、区）均设置东、南、西、北、中5个采样点，共70个采样点，采用夹夜法于2021年10月－2022年10月开展遵义市2022年度鼠类及其病原学监测。对捕获到的小型兽类（小兽）标本进行种类鉴定和病原体检测，采用Excel 2021软件进行数据整理，SPSS 26.0软件进行统计学分析，计数资料分析采用率或构成比之间的χ²检验，P < 0.05为差异有统计学意义，分析小兽密度、种类构成和病原体携带情况。结果: 各监测点共布放有效夹9 969夹次，捕获小兽549只，其中鼠类522只，小兽总密度为5.51%，总鼠密度为5.24%，红花岗区鼠密度最高，为12.94%，其次是凤冈县，为12.34%，赤水市最低，为1.80%，各县（市、区）鼠密度差异有统计学意义（χ²=195.619，P < 0.001）。城镇居民区、农村居民区和重点行业的优势鼠种均为褐家鼠，农田耕地以黑线姬鼠为优势鼠种。遵义市不同区域（中部、北部、东部、西部）小兽种类构成差异有统计学意义（χ²=117.357，P < 0.001）。取每只小兽标本的肝、脾和肾[问号钩端螺旋体（钩体）、恙虫病东方体]、肝、脾和肺（大别班达病毒）和肺（汉坦病毒）进行病原体检测，共抽取检测标本343份，检出病原体阳性27份，阳性病原体均为问号钩体，病原体检出率为7.87%，其中鼩鼱检出率最高，为16.00%，其次为黑线姬鼠（12.35%），褐家鼠最低（1.64%），不同种类小兽检出率差异有统计学意义（χ²=14.372，P=0.002）；农田耕地小兽问号钩体检出率最高，为9.66%（26/269），重点行业检出率为2.94%（1/34），城镇居民区和农村居民区均未检出，不同生境类型检出率差异无统计学意义（χ²=5.171，P=0.160）；湄潭县小兽问号钩体检出率最高，为27.03%，其次为绥阳县（25.00%），仁怀市、凤冈和余庆县未检出，不同地区检出率差异有统计学意义（χ²=35.409，P=0.001）。结论: 遵义市鼠密度较高，检出问号钩体，需警惕相应疾病的发生，各地应积极响应，加强春、秋季灭鼠工作，根据各生境优势鼠种和病原体检出情况，并结合各地区实际采取综合防制措施，降低鼠密度，防止鼠传疾病的发生。

关键词: 鼠类监测, 鼠密度, 小型兽类, 种类构成, 病原体