Antiparasitic Efficacy of 10% w/v Fipronil Spot-on (Fiproline Spot-on) against Experimental Tick (Rhipicephalus sanguineus) Infestations on Dogs

Abstract

This study was conducted to investigate the efficacy of 10% w/v fipronil spot-on for treatment and prevention of Rhipicephalus sanguineus infestations on dogs. Twelve Beagles were randomly separated into two
groups which were treatment and control group (6 dogs/group). The treatment group received 10% fipronil spot-on at the dosage of 6.7 mg/kg on day 0. A group of 60 Rhipicephalus sanguineus was released to feed on each dog on day -7, -2, 7, 14, 21, and 28. The ticks were counted and removed on days-4, 3, 10, 17, 24, and 31. Mean number of tick
infestations in the control group ranged from 16.67-24.50 ticks per dog and the attachment rate ranged from 27.78-40.83%. Mean number of tick infestations in the treatment group on the days before fipronil was applied on the dogs was 21.67 ticks per dog and the attachment rate was 36.11%. Percent efficacy of fipronil used in this study was 71.77, 96.03, 100, 91.84, and 90.21% on days 3, 10, 17, 24, and 31, respectively. There were statistically significant differences between the mean numbers of tick between the control and treatment groups on days 3, 10, 17, 24, and 31. There was no significant difference of complete blood count and kidney and liver functions before and after the study. Skin rash did not show up in the treatment group after fipronil was applied on the dogs.