氯硝柳胺堆敷灭螺法用药剂量的探讨

目的探讨氯硝柳胺堆敷灭螺法的合理用药量。方法在四川省普格县特兹乡选择地理位置相邻、钉螺密度较高且相似的6块渗水草地作为氯硝柳胺堆敷灭螺试验现场。各试验组的氯硝柳胺用药量分别为16、8、4、2、1g/m2和0,5个月后采用系统抽样法进行螺情调查以考核灭螺效果。结果灭螺5个月后,4g/m2及以上剂量组均未再查出活螺;其他3个组均能查到活螺,其中1g/m2组和对照组尚能查到幼螺,但该3组与灭螺前相比,活螺框出现率和活螺平均密度均大幅度下降(P均0.05),钉螺死亡率均明显上升(P均0.05)。堆敷灭螺法的人工费用为0.45元/m2。结论堆敷灭螺法是一种较为理想的灭螺方法 ,其现场使用的合理剂量为4g/m2。

Study on dosages of niclosamide for Oncomelania snail control with a "heaping" method

Objective To explore an appropriate dosage of niclosamide in the ＂heaping＂ method.Methods Six sods with water,which were contiguous,with the similar density of snail were selected as the study fields in Tezi Township,Puge County,Sichuan Province.The dosages of niclosamide were 16,8,4,2,1 g/m^2 and 0,respectively.The effects of snail control were assessed after 5 months.Results After 5 months,no living snails were found in these study sites with the dosage of 4 g/m^2 and more.However,some living snails were still found in the other 3 study sites,especially in the control group（0 g/m^2）and in the group with a dosage of 1 g/m^2,some juvenile snails could be found.The occurrence rate of frames with living snails and the average densities of snails significantly reduced （P〈0.05）,and in the 3 study fields with the dosages less than 4 g/m^2,the mortality of snails significantly increased （P〈0.05）.The manpower cost of the ＂heaping＂ method was 0.45 Yuan/m^2.Conclusion The ＂heaping＂ method is an effective measure for snail control and its recommended dosage is 4 g/m^2.