关键词: 生物学测定方法, 印鼠客蚤, 缓慢细蚤, 猫栉首蚤, 溴氰菊酯, 触杀效果

Abstract: Objective To establish a method for flea susceptibility bioassay to contact insecticides,and to supply an easy technology for the study of fleas insecticide susceptibility evolution,resistance selection,resistance inheritance,and insecticide exploitation.Methods Applied 100 μl insecticide acetone or ethanol solution on a 35 mm diameter filter paper disk,put it into a 50 ml centrifugal tube lid,about 15 adult fleas were pleased into the tube with 20 holes(diameter 0.5 mm) and than covered and fastened the lid immediately,inversed the tube to let fleas contact the insecticide freely.Treated insects were held in an incubator without light,a temperature of(25±1)℃,and RH(80±5)%.The survivors were recorded after 24 h,LC₅₀s and 95% fiducial limits were estimated by DPS system.The method was estimated and applied for susceptibility bioassay of Xenopsylla cheopis,Leptopsylla segnis,Ctenocephalides felis felis.Results There were no significant difference of susceptibility to deltamethrin among 5,26,30 and 37 d eclosion non-suck blood meal X.cheopis with a sex ratio ♀∶♂=1∶0.2-1∶3.1,the LC₅₀s were from 0.1236 to 0.2371 μg·ai/cm².The LC₅₀s of female and male were 0.2068(0.1007-0.4874) and 0.2234(0.1986-0.2529)μg·ai/cm² respectively,they were very similar.Comparing to non-blood suck fleas,fleas sucked blood meal with a LC₅₀ value 0.3283(0.2618-0.4359)μg·ai/cm² decreased susceptibility significantly.For L.segnis,X.cheopis and C.felis felis,the LC₅₀s were 0.1236(0.0905-0.1578),0.0071(0.0052-0.0103) and 11.4708(5.8633-43.6013)μg·ai/cm² respectively,there was a very significant difference among them.Conclusion This contact insecticide effective evaluating method is characterized by easily operating,avoiding the fleas escaping,higher repetitive,but standard testing insect,the same insecticide and standard method should be used.