Abstract
A control trial of adult house flies, Musca domestica, was done with cyfluthrin mixed with piperonyl butoxide on a pig farm located in Narita-shi, Chiba Prefecture in September and October, 1988. One hundred house flies each collected on the farm were put into 13 cages, with one cage assigned as a non-treated control and the others treated: Two cages were sprayed with tap water in volumes of 50 ml/m2 and 100ml/m2, respectively. Four cages were sprayed with 100-, 200-, 400-, and 800-fold dilutions of a mixture, (at a ratio of 1: 5 calculated as active ingredients, ) of cyfluthrin 5%(W/W) emulsion and piperonyl butoxide in a volume of 50 ml/m2. The other 4 cages were sprayed with 200-, 400-, 800-, and 1600-fold dilutions of the same mixture in a volume of 100 ml/m2. To the remaining 2 cages, 200-and 400-fold dilutions of permethrin 4%(W/W) emulsion including a synergist were sprayed in volumes of 50 ml/m2 and 100 ml/m2, respectively As a result, cyfluthrin took a dose-dependent insecticidal effect, and the effect was almost the same regardless of the spray volume when the same amounts of active ingredient were sprayed. It was also observed that cyfluthrin developed higher efficacy than permethrin in the same amounts Based on the above results, 200-fold dilution of the mixture of cyfluthrin 5% emulsion and piperonyl butoxide was applied to house flies in the pig house in a volume of 50 ml/m2, followed by an application 20 days later with 400-fold dilution in the same volume. Both applications, especially that with the 200-fold dilution, reduced the number of fllies greatly in the house.
