Molecular and Biological Characterization of Haemaphysalis Leachi (Acari: Ixodidae) in Nigeria West Africa

Abstract

Ticks constitute a serious threat to the wellbeing of humans and other animals. The accurate identification of ticks is paramount in epidemiological investigations. Genetic markers have been identified and used to overcome the limitations of phenotypic identification of ticks. In this study, the cytochrome c oxidase 1 (Cox1) gene was amplified and sequenced for the identification of Haemaphysalis leachi, the putative vector of Babesia rossi in Nigeria. Amplification was successful in 34 out of 39 (87 %) ticks collected from dogs in three Nigerian states with sequence homology of 99 % to H. leachi in Genbank (GenBank: MN663156.1). Maximum Likelihood phylogenetic analysis showed significant grouping of H. leachi sequences in independent monophyletic subclade with a bootstrap value of 100 %. Genetic distance analysis of H. leachi identified in this study indicated a very low level of intraspecific diversity (0.016 %) compared to 0.150—0.190 % interspecific distance to other Haemaphysalis species. The number of eggs laid by engorged female ticks maintained in the laboratory ranged from 885 to 2190 and was proportional to the ticks’ initial weight. The mean value of other biological parameters; female engorgement weight, pre-oviposition period, oviposition period, total egg mass, egg size, efficiency rates of female ticks in converting their food reservoir to eggs and incubation period are, 147.5 mg, 7.8 days, 13.2 days, 59.5 mg, 485.5 × 348.7 µm, 41.2 % and 26.2 days, respectively. This study reports the first molecular identification of H. leachi in Nigeria.

Keywords

• cox1
• identification
• ixodidae
• nigeria
• pcr
• sequencing