钉螺耐寒能力的实验研究

Study on cold hardiness of Oncomelania snails in laboratory

目的实验室恒温条件下初步观察钉螺的耐寒能力,推测钉螺在空气环境下的致死低温。方法现场采集安徽贵池的湖北钉螺指名亚种(Oncomelaniahupensishupensis),在实验室条件下测定钉螺在不同温度及不同时间下的存活情况。结果钉螺直接暴露在空气中的死亡率和温度、暴露时间关系的logistic回归方程为MORTALITY=1-1/[1+e(-6.0518-0.6584×TEMPERATURE+0.1014×TIME)],温度和时间的OR值分别是0.518(95%CI=0.503,0.534)、1.107(95%CI=1.096,1.119)。结论干燥环境下钉螺暴露0.125~24h的LT50在-9.17^-5.49℃之间,在-15℃暴露5min以上则全部死亡。

Objective To research the cold hardiness of snails in the constant temperature condition in laboratory, and speculate on the lower lethal temperature of snails in dry air. Methods Snails named Oncomelania hupensis hupensis were collected from the marshland in Guichi, Anhui Province and exposed to different temperature environments for different time in the laboratory, and the mortality was investigated. Results The logistic regression equation between the mortality of the snails exposed directly to dry air and the temperature and the time was MORTALITY= 1-1[1＋e^（-6.0518-0.6584×TEMPERATURE＋0.1014×TIME）], and the OR values of temperature and time were 0. 518 （95%CI=0.503,0.534）,1.096（95%CI=1.085,1.108）, respectively. Conclusions The LT50 of snails exposed to dry air for 0. 125-24 hours is between-9.17℃ and -5.49℃, and snails will die in 5 minutes if they are exposed to the 15℃ dry air.