Eficácia de uma formulação “Spray” de Fipronil associado ao Piriproxifen no controle de Ctenocephalides felis felis (Bouché, 1835) e Rhipicephalus sanguineus sensu lato (Latreille, 1806) em cães artificialmente infestados

Abstract

The objective of this work was to evaluate the efficacy of a product in the spray formulation containing the combination of fipronil and pyriproxyfen in the control of Ctenocephalides felis felis and Rhipicephalus sanguineus. This study consisted of three distinct studies, and the combination of fipronil and pyriproxyfen at the concentrations of 7.5 and 4,44mg/kg respectively, was administered to all dogs in the treated group. The animals in the control group did not receive any type of treatment. For the evaluation of pulicidal and acaricidal efficacy, 14 dogs were used, divided into two experimental groups. The infestations were carried out with 100 specimens of C. felis felis and 50 of R. sanguineus, and occurred on days: +5, +12, +19, +23, +26, +33, +40, +47, +54 , +61, +68 and +75. The evaluations for the calculation of effectiveness occurred on days: +2, +7, +14, +21, +28, +35, +42, +49, +56, +63, +70 and +77. The acaricidal efficacy was greater than 90% for up to 28 days, while the pulicidal efficacy was greater than 90% for up to 63 days. For the evaluation of the action of speed of kill 36 dogs were selected, divided in six experimental groups. Dogs were infested on days -2, +5, +12, +19 and +26 with 100 specimes of C. felis felis and 50 of R.sanguineus. The evaluations were carried out at two, four and 24 hours after treatment and infestations for a period of 28 days. The counting dates of the parasites for the determination of efficacy were on the experimental days 0, +1, +7, +8, +14, +15, +21, +22, +28, +29. Regarding the acaricidal efficacy, the association did not show efficacy greater than 90% in any of the experimental moments. However, in terms of pulicidal efficacy was greater than 90% in the two-hour assessment group for seven days, in the four-hour assessment group for 14 days, and in the 24-hour assessment group for 28 days. For the study of the action in the inhibition of the development of egg to adult of C. felis felis were used 12 dogs, forming two experimental groups. Infestations with 200 specimens of C. felis felis occurred on days: -7, -2, +7, +14, +21, +28, +35, +42, +49, +56, +63, +70 , +77, +84, +91 and +98. The evaluations for the calculation of pulicidal efficacy and collection of kennel eggs were performed on days + 2, +10, +17, +24, +31, +38, +45, +52, +59, +66, +73 , +80, +87, +94 and +101. The recovered eggs were incubated in two repetitions containing 20 eggs, for a period of 30 days. After this period, the number of emerged adult fleas was counted in each repetition to determine the emergency percentage. The association tested showed more than 90% efficacy in control of C. felis felis adults for up to 45 days, reduced egg production by 52 days and emergence of adults for 66 days. The association tested is effective for the control of R. sanguineus and C. felis felis in artificially infested dogs.