Efficacy of the association of cypermethrin, chlorpyriphos, piperonyl butoxide and fluazuron against larvae of Dermatobia hominis in naturally infested cattle

Abstract

The objective of this study was to evaluate the efficacy of a product ectoparasiticide containing an association of cypermethrin, chlorpyrifos, butoxide pireronila and fluazuron in formulating "pour on" the fly control D. hominis in cattle naturally infested. For this, were used twenty bovines, half-breed, without distinction of sex or age. All animals included in the study had naturally occurring D. hominis larvae on both sides of the body. The animals in the treated group were medicated with the combination of cypermethrin (5mg / kg), chlorpyrifos (7mg / kg), pireronyl butoxide (5mg / kg) and fluazuron (2.5mg / kg) at a dose of 1ml for every 10 kg live weight, "pour on" in single-dose. The larvicidal efficacy for D. hominis efficacy was evaluated seven and 14 days after the treatment, from the nodule count of live larvae in the animals of the two groups. The mean number of live larvae in the control group was 24.4 ± 8.11, 23.2 ± 6.49, 25.9 ± 8.97 and in the treated group 24.7 ± 8.34, 1.1 ± 1 , 04 and 0.7 ± 0.78 on days zero, seven and 14 days after treatment The efficacy of the association tested in this study was 95.26% and 97.30% on days 7 and 14 respectively. The association of cypermethrin, chlorpyrifos, pyreronyl butoxide and fluazuron in the pour-on formulation is effective in controlling D. hominis in naturally infested cattle.