灭蚊真菌贵阳腐霉对几种动物的急性安全性测试

A Report of Acute Experiments on the Safety of Pythium guiyangense SU to Several Kinds of Animals

目的:了解灭蚊真菌贵阳腐霉(Pythium guiyangenseSU)对非靶动物是否有毒害作用。方法:用贵阳腐霉菌丝体及游动孢子以灌胃法和腹腔注射法处理小鼠,观察小鼠的食欲、活动等一般情况并监测体重;用贵阳腐霉菌丝体通过经皮、黏膜染毒,过敏休克试验,接触过敏试验等方法处理豚鼠、家兔、鱼、鸡等动物,观察动物受试部位的局部变化及一般综合情况。结果:真菌菌丝体对小鼠经口LD50(1600 mg/kg,经腹腔注射LD50(400mg/kg;游动孢子经口、腹腔注射的LD50(104孢子/ml,对小鼠、豚鼠、家兔等无感染致病性;对皮肤、黏膜无刺激性,试验动物无超敏反应表现。结论:灭蚊真菌贵阳腐霉对小鼠、豚鼠、草鱼、金鱼以及家禽等受试动物是安全的,是一株具有开发应用价值的灭蚊真菌,为贵阳腐霉防治蚊虫的推广应用及安全使用提供了毒理学依据。

Objective： To investigate if there possibly exist toxic effects of Pythium guiyangense SU, a mosquito-killing fungus isolated in Guiyang, China in 1994, on several non-target animals. Meth- ods： Acute safety experiments were conducted on mice, guinea pig, rabbit, fish and chicken with the fungus including： （1） pouring mycelia into the stomach, or injecting mycelia or zoospores into peritioneal cavity of mice; （2） putting mycelia onto the skin and mucous membrane of mice, guinea pig, rabbit, fish and chicken to test allergies or toxic reaction. Changes of the animals general conditions were observed for 28 days. Results： No proof was obtained that the fungus caused any mycetic disease in these animals. The LD50 dosages of mycelia to mice were higher than 1600mg/kg by oral adminis- tration and higher than 400mg/kg through intraperitoneal injection, while those of zoospores were high- er than 104/ml via both the two ways. Contiguity tests didn＇t cause supersensitive reaction. Conclu- sions： P. guiyangense does not show pathogenicity to these animals tested. Since they are good repre- sentatives of mammals, birds and fish, and the experiments were designed strictly following the nation- al regulations for drug tests, the research results have given us confidence that P. guiyangense should be a safe agent for mosquito biocontrol.