Detection of Toxoplasma gondii (Apicomplexa: Sarcocystidae) in the Brown Dog Tick Rhipicephalus sanguineus (Acari: Ixodidae) Fed on Infected Rabbits

Abstract

The brown dog tick Rhipicephalus sanguineus is a three-host tick that feeds primarily on dog and occasionally on other hosts, including human. Toxoplasmosis is generally considered the most important disease that causing abortion of both pregnant women and different female animals throughout the world. Therefore, the aim of this study was to determine the ability of the brown dog tick R. sanguineus to acquire Toxoplasma infection through feeding its larvae on experimentally infected rabbits with T. gondii. The R. sanguineous larvae were feed on rabbits experimentally infected with locally isolated virulent Toxoplasma gondii strain. Nymphs moulted from these larvae were investigated to detect the presence of T. gondii specific B1 gene DNA using PCR at 193 bp. Histological examination for liver, lung and heart of experimentally infected rabbits was performed to confirm the infection of animals with T. gondii. The histopathological examination of infected rabbit tissues (heart, lung liver) revealed infiltration of T. gondii tachyzoites and polymorph nuclear inflammatory cells in addition the presence of different tissue alterations and degeneration other than that in normally histological tissues of non-infected rabbits. The nymphs of R. sanguineus were free from T. gondii. Further investigations are needed on the other developmental stages of R. sanguineus to ensure the ability of this tick species in transmission of T. gondii.