Tickicidal efficacy of a spot-on formulation of fipronil directly applied against tick dorsal side

Usability as a supplementary method for treating tick infestation in dogs

Abstract

Ticks occur frequently on dogs, to which they often transmit pathogens of many types, including zoonotic pathogens. Therefore, they should be eliminated quickly. This study evaluated direct application of a spot-on formulation of fipronil to ticks’ dorsal side. For this study, 128 ticks on 30 dogs were treated with the formulated fipronil at a dosage of 5 µL or 500 µg active ingredient. For 104 ticks on the other 30 dogs, a proper dosage was applied with a cotton swab. Within 3 hr, 94% and 96% ticks were eliminated, respectively: all were eliminated within 6 hr. No adverse event was observed for any dog. Direct application of this drug was adopted as a complementary treatment of tick infestation.