RESUMO
Two insect growth regulators, Methorprene and Hydroprene were evaluated as growth hormones one the common house dust mite; Dermatophagoides farinae. The adults and immature stages were treated with 4 concentrations of each regulator as contact and as diet. The data were recorded 30 and 90 days post- exposure. Both compounds significantly suppressed population growth, as compared to >/= 5% acetone controls. Methoprene was more effective than Hydroprene when given in diet by corporation bioassays but, slightly more effective for the 1st 30 days of the contact assays. A second set of contact and diet -incorporation assays was done using a 75% of Methoprene and Hydroprene to determine efficacy on D. farinae population dynamics, at weekly intervals for 13 weeks. The average number of the mites in the untreated control population was increased by more than 10 times than the original ones. One the other hand, the number of treated mites was not significantly increased. This was similar for both the contact and the diet-incorporation bioassays, although the average number of mites/container was significantly higher when the treatment was incorporated in the house dust mite diet than when applied directly as contact. Consequently, the insect growth regulators minimized the allergic efficacy of D. farinae experimental exposed mice