作者自1971年夏起在美国路易斯安那释放奈氏线虫(Reesimermis nielseni)处理孳生地,直到1974年冬,尽可能地逐周抽样检查,每个样品随机捞捕50条幼虫,按蚊种和龄期分别解剖检查感染线虫情况;必要时,对幼龄幼虫保持到可加鉴别。有时孳生地因缺少幼虫或缺水而采不到样品。每年12月初至次年3月底为低温季节,不利于线虫的 The authors released the breeding grounds for Reesimermis nielseni from Louisiana in the summer of 1971 until the winter of 1974 and conducted weekly sampling inspections whenever possible. Fifty larvae, Necropsy were conducted to examine the nematode infection at each instar, and young larvae were maintained until they were identified as necessary. Occasionally, samples can not be collected due to lack of larvae or lack of water. Every year from early December to the end of March next year for the cold season, is not conducive to nematodes