氯代水杨胺灭螺效果的实验研究

目的 观察氯代水杨胺的灭螺效果和对鱼苗的毒性。 方法 配制不同浓度的氯代水杨胺，用浸泡法、喷洒法观察不同浓度和不同作用时间的灭螺效果，并进行鱼苗毒性实验。氯硝柳胺乙醇胺盐作对照。 结果 氯代水杨胺的浓度为0.25和0.5 mg/L，浸泡48 h，钉螺死亡率分别为97.8%、100%，半数有效致死浓度（LC₅₀）为0.067 4 mg/L；氯硝柳胺乙醇胺盐浓度为0.25和0.5 mg/L，浸泡48 h，钉螺死亡率分别为22.2%、66.7%，LC₅₀为0.3976 mg/L。药物浓度为0.4 mg/L喷洒1、3、7和15 d，氯代水杨胺的灭螺率分别为90%、100%、100%和100%；氯硝柳胺乙醇胺盐的灭螺率分别为60%、70%、70%和50%。0.25 mg/L浸泡48 h，氯代水杨胺和氯硝柳胺乙醇胺盐刺激钉螺离水上爬率分别为32.2%和46.7%。0.4 mg/L药物作用72 h，氯代水杨胺和氯硝柳胺乙醇胺盐的鱼苗死亡率分别为50.0%和100%。 结论 氯代水杨胺有灭钉螺作用，对鱼苗毒性比氯硝柳胺乙醇胺盐略低，并有抑制钉螺上爬作用。

Study on Molluscicidal Effect of Chlorosalicylicamide

OBJECTIVE: To observe the molluscicidal effect of chlorosalicylicamide on Oncomelania hupensis and toxicity on fishes. METHODS: Different concentrations of chlorosalicylicamide were prepared, and immersion and spraying methods were used to test its molluscicidal effect and toxicity to fishes. Niclosamide ethanolamine salt was used as control. RESULTS: Under water temperature of 28 C with the dose of chlorosalicylicamide at 0.25 mg/L and 0.4 mg/L, the mortality rate of snails by immersion was 97.8% and 100% respectively after 48 h, and the LC50 was 0.0674 mg/L. While for niclosamide at the same doses, the mortality rate of snails was 22.2% and 66.7% respectively, and the LC50 was 0.397 6 mg/L. With the concentration of 0.4 mg/L for 72 h, the fish death rate in chlorosalicylicamide and niclosamide was 50.0% and 100% respectively. CONCLUSION: Chlorosalicylicamide shows a molluscicidal effect on Oncomelania snails and a lower toxicity to fishes than that of niclosamide.