MOLECULAR CHARACTERIZATION OF TICK-BORNE PARASITES IN NATURALLY INFECTED CATTLE IN ACCRA AND ADIDOME, GHANA

ABSTRACT

Tick-borne pathogens and ticks pose significant problem to livestock production especially cattle production. This causes huge economic decline to livestock farmers in tropic and sub-tropic regions of Africa. The most economically important tick-borne pathogens to the production of bovine include Babesia, Anaplasma, Theileria and Ehrlichia. In Ghana, inadequate data exists on the species and genetic diversity of tick-borne hemoparasites. The current study was conducted to detect and characterize tick-borne pathogens and determine their genetic diversity in naturally infected cattle in two agro-ecological zones in Ghana. A total of forty cattle, twenty from each study site were sampled at four to five week interval over a duration of six months. A nested PCR amplifying the 18S rRNA gene was performed to detect the presence of tick-borne parasites. Host and environmental factors were assessed to determine whether they played a role on frequency of detection of these parasites. Species and genetic identity of the tick-borne parasites were established through sequencing of their 18S rRNA gene amplicons followed by sequence homology search at NCBI DNA data base and phylogenetic analysis of the sequenced amplicons.

Theileria species and Babesia species were the two genera of tick-borne pathogens identified. T. velifera was the predominant species of tick-borne hemoparasite identified at both study locations. Also, T. mutans and B. bovis were identified at Accra and Adidome respectively. The tick-borne parasites exhibited diverged dynamics of infection throughout the period of the study. Breed of cattle significantly affected the frequency of detection of the tick-borne parasites. Environment and sex did not play a role in the frequency of detection of the parasites. There was no genetic diversity between the same species of parasites identified from the same agro-ecological zones.