Effect of Abamectin on Reproduction and Development of an Avian Tick, Argas (Persicargas) arboreus (Ixodoidea: Argasidae)

Kairiyah Aboutaleb,Shimaa Ahmed,Nawal Shanbaky,Nadia Helmy

doi:10.21608/eajbsa.2019.59645

Abstract

Topical application of a single dose (10µl/tick or egg batch) of different concentrations of abamectin (an avermectin) has lethal and biological effects on the engorged mated adult female, immatures and egg of Argas (Persicargas) arboreus that induced 100% mortality at 25,15 and 10 ppm, respectively. Abamectin treatment at lower concentrations of 1-10 ppm interfered with the female reproduction, nymphal and egg development. Abamectin topical (3-10 ppm) application on mated engorged adult female A. (P.) arboreus at different intervals of its reproductive cycle reduced fecundity and fertility of the female, prolonged its preoviposition, oviposition and the egg incubation periods. The effects were most prominent during vitellogenesis and the least at the start of oviposition. Abamectin treatment of the newly moulted fed 2nd nymphal instar, delayed its moulting and of the resulted 3rd instar and reduced adult emergence. The treatment caused paralysis and various deformities (15.6-28.6%) as missing legs at the coxal level, changes in colour and failure to moult or to detach the old exuvia in the resulted 3rd nymphal instar. Egg batch treatment by dipping the freshly deposited eggs for 20 seconds in an aqueous solution of 1-5 ppm abamectin was more effective in reducing normal hatching, increasing unhatching and total inhibition of egg development than topical treatment. However, both methods of treatment similarly prolonged the egg incubation periods and caused abnormal hatching, malformations, and anomalies in the eggs and embryos

Highlights

The tick, Argas (Persicargas) arboreus Kaiser, Hoogstraal, and Kohls (Khalil et al, 1980) infests herons and other medium size wading birds in their heronries in many areas of Africa
Application of Abamectin: 1. Female Treatment: For biological studies on reproduction, a single dose (10μl/tick) of three selected concentrations (3,5 and10 ppm) of abamectin was used to apply, where preliminary experiment showed that higher doses either completely prevented egg production or hatching and caused very slow motion and mortality of the females to reach 100% at 25 ppm within 10-20 days after treatment
Abamectin treatment at lower concentrations of 1-10ppm interfered with female reproduction, nymphal and egg development

Summary

Introduction

The tick, Argas (Persicargas) arboreus Kaiser, Hoogstraal, and Kohls (Khalil et al, 1980) infests herons and other medium size wading birds in their heronries in many areas of Africa. In Egypt, Argas (P.) arboreus is a host of the bacterium, Salmonella typhimurium (Floyd & Hoogstraal 1956), the rickettsia microorganism, Wolbachia persica (Suitor & Weiss 1961) and the spirochete Borrelia anserina (Hoogstraal, 1985). It is naturally infected with Quaranfil and Nyamanini viruses (Taylor et al 1966, Hoogstraal 1966). Protection of the cattle egret B. ibis becomes more efficient by increasing our knowledge on the bird relationships with its environment and biological associates especially vectors of disease agents such as parasitic ticks and their control

Methods

Results

Conclusion