湖沼型钉螺迁徙水网地区8年生存状况的研究

A research on the living status of the imported Oncomelania snails from lakes in water network regions during 8 years

目的通过模拟观察湖沼型钉螺迁徙水网地区8年生存和繁殖情况,探讨湖沼钉螺在水网地区是否具有持续的生存繁殖能力,为血吸虫病防控中钉螺异地迁徙中的螺点形成提供参考依据。方法采用安徽贵池野生钉螺,按照雌雄各25、50、100、200、400、800只的剂量,于2010年11月25日随机放养于专建的4 m2/池的钉螺实验研究池中连续观察2922 d,每日观察记录实验池中泥土表面的钉螺及子代新螺活动情况,进行统计分析。结果观察期间,各投螺池中泥土表面的总螺量呈下降趋势,不同年度同一剂量和同一年度不同剂量钉螺总数、不同年度同一剂量子代螺总数和同一年度不同剂量子代螺总数差异均有统计学意义(P<0.05)。结论湖沼型钉螺离开原生存地至水网地区可以生存繁殖但难以持续繁殖生存,提示血吸虫病防治工作中钉螺监测的重点应放在本地区和邻近有螺地区的监测,而非关注跨地区远距离播散的钉螺监测。

Objectives To know the living and reproducing status of the imported Oncomelania snails from lakes in water net regions during 8 years,and provide evidences on imported snail spots forming for preventing and controlling schistosomiasis.Methods 6 ponds of 4 square meters each were provided where there were 25,50,100,200,400,800 pairs of wild snails respectively from Guichi,Anhui on November 25 th,2010.During the 2922 days,the amounts of the total snails and the second birth snails on the surface of the soil were recorded and then analyzed.Results There was a descending trend of the total snails in each pond.According to the Kruskal Wallis tests,there were significant differences of the total snails and the second birth snails among the doses of the same year and the years of the same dose(P<0.05).Conclusion Imported snails from lakes could survive in water net region,but then could not reproduce continuously,which indicated that local snails or neighborhood snails rather than the remote trans-regional imported snails should be monitored in preventing and controlling schistosomiasis.