Abstract:

Objective To study the survival and reproduction of mountain,water network and lake endemic areas and density Oncomelania in water network region, and to investigate the possibility of Oncomelania which come from mountain and lake endemic areas imported to water network areas, provided scientific basics for the prevention and control of imported Oncomelania snails. Methods The experimental field was located in a water network endemic area at Xiuzhou district of Jiaxing city, Zhejiang province. The experimental field was divided into three group and located in Xiuzhou district of Jiaxing city. The snails were collected from Jinhua city of Zhejiang province(mountain endemic area), Xiuzhou district of Zhejiang province(water network endemic area)and Guichi of Anhui province(lake endemic area)which were divided into 2, 4, 6, 8, 10, 20, 40 snails each cage in low density groups, and 80, 100, 150, 200, 400, 800 snails each cage in high density groups. The snails were paired with female and male in low density groups and random grouped in high density groups. The reproduction situation was observed one year later. Results The survival rates of Oncomelania snails from mountain, water network and lake endemic areas were 17.45%, 4.95%, and 7.47%, and were 48.33%, 35.56%, and 34.44% in low density groups and were 15.84%, 3.35%, and 6.07% in high density groups,respectively. The reproduction rates of Oncomelania snails from mountain, water network and lake endemic areas were 1.99, 3.10, and 1.95, and were 14.48, 24.81, and 11.42 in low density groups and were 1.34, 1.97, and 1.46 in high density groups, respectively. The differences of survival and reproduction rates of Oncomelania snails between low and high density groups in different endemic areas were statistically significant (P<0.05). Conclusion The Oncomelania snails coming from different endemic areas could survive and reproduce in the water network regions,and there were negative correlation between survival and reproduction rates and snails density.

Key words: Endemic areas, Oncomelania, Density, Reproduction regularity

摘要：

目的 调查山丘型、水网型和湖沼型血吸虫病流行区不同密度的钉螺在水网型流行区的生长繁殖情况，分析其他流行区钉螺输入水网型流行区的可能性，为防止钉螺输入和实施防控措施提供科学依据。方法 2014年4月选择水网型血吸虫病流行区浙江省嘉兴市秀洲区，设立钉螺繁殖现场试验地点，将山丘型流行区（浙江省金华市）、水网型流行区（浙江省秀洲区）和湖沼型流行区（安徽省贵池区）钉螺分3个实验组，每组按每框（0.1 m²）2、4、6、8、10、20、40、80、100、150、200、400、800只的钉螺密度进行投放，其中低密度（≤40只/框）各组雌雄配对，高密度（>40只/框）各组随机组合，养殖1年后观察各组钉螺生存繁殖情况。结果 山丘型、水网型和湖沼型钉螺存活率分别为17.45%、4.95%和7.47%，低密度组存活率分别为48.33%、35.56%和34.44%，高密度组存活率分别为15.84%、3.35%和6.07%。3种不同流行区钉螺繁殖倍数分别为1.99、3.10和1.95，低密度组繁殖倍数分别为14.48、24.81和11.42，高密度组繁殖倍数分别为1.34、1.97和1.46。不同流行区钉螺低密度及高密度组间的存活率和繁殖倍数差异均有统计学意义（P<0.05）。结论 不同流行区钉螺均可在水网型流行区生长繁殖，钉螺存活率和繁殖倍数均与其密度呈负相关。

关键词: 流行区, 钉螺, 密度, 繁殖规律