Evaluating the effectiveness of varying concentrations of permethrin on ticks of genus Aponoma on Royal Pythons (Python Regius)

Abstract

Quarantine programs in zoological gardens for reptiles including snakes can only be complete with acaricide treatment due to heavy infestation of ticks especially Aponoma species. The ticks can pose health threats to snakes including death few days to weeks after tick bite. The toxic effects of most available acaricides are grievous as snakes find it difficult to metabolize those drugs readily. The present study therefore focused on identifying these tick vectors and employing a modified method of acaricidal application on Python regius in order to reduce toxicity and health risks due to the acaricidal effect. The study was carried out in Royal python (Python regius) located at University of Ilorin Zoo, Ilorin, Nigeria. A total of ten Royal pythons were selected for the study. The snakes were randomly allocated to four groups (A, B, C and D), each group containing three snakes (A,B,C) and the last snake used as control(D). Off-shelf permethrin acaricide was diluted to three different concentrations and applied to the snake followed by a wiping-off mechanism at the concentration of 0.1%, 0.05% and 0.025% for treatment of groups A, B and C, respectively. The concentration of 1mg/ml (0.1%) produced the best result in terms of efficacy (using Abbott formula), tolerance and repeatability. The result obtained at 0.25 mg/ml (0.025%) concentration did not produce a desired effect with an efficacy of 85% compared with 100% obtained in 1mg/ml group, after treatment. This study therefore establishes that 1mg/ml (0.1%) permethrin produced the best result in terms of efficacy, tolerance and repeatability and can also be applicable in other snake species adhering to the protocols used in this study.

Keywords: acaricides, permethrin, royal python, Aponoma, zoo, Nigeria