A comparison of the efficacy of two commercial acaricides (fipronil and amitraz) with Azadirachta indica (neem) on the brown dog tick (Rhipicephalus sanguineus) from canines in Trinidad

ABSTRACT

Objective: Rhipicephalus sanguineus, the most common species of tick found on canines in Trinidad. It is a potential vector for potentially fatal zoonotic diseases such as borreliosis (Lyme disease), babesiosis, anaplasmosis and human granulocytic ehrlichiosis. Common acaricides used by pet owners such as fipronil and amitraz are often misused and abused as owners may fail to follow the manufacturers' instructions. The objectives of this study were to compare the efficacies of the commercial acaricides (fipronil and amitraz) to the herbal alternative, neem on brown dog ticks in Trinidad. Design and Methodology: The Larval Packet Test (LPT) was conducted in triplicate for each of three concentrations (high, recommended and low concentrations) of fipronil, amitraz, neem oil and neem leaf extract. STATA version 15 was used to perform a mixed effects Poisson regression analysis. Results: Both the commercial and herbal acaricides were effective in causing death of the larvae. Larvae were susceptible to amitraz and fipronil at all concentrations used, however they displayed variable resistance to the neem oil and neem leaf extract. Conclusions: The commercial preparations (amitraz and fipronil) proved to be more effective than neem oil and neem leaf extract, however the latter can be used as a herbal alternative to control R. sanguineus in Trinidad.