Ixodid ticks of traditionally managed cattle in central Nigeria: where Rhipicephalus (Boophilus) microplus does not dare (yet?)

Background: Ticks and tick-borne diseases (TBDs) undermine cattle fitness and productivity in the whole of sub-Saharan Africa, including Nigeria. The aim of this study was to document the composition of tick species, assessing the burden of infestation, in traditionally managed cattle in an area of central Nigeria where acaricides have not been used historically. Methods: The study was carried out in September 2010 in 9 villages belonging to three neighbouring local government areas in Plateau State, Nigeria. In each village all visible adult ticks were collected from at least 15 cattle (mean number = 25). Collected ticks were preserved in 70% ethanol to be counted and morphologically identified to the species level. Results: A total of 5011 ixodid ticks (1935 males and 3076 females) were collected from 228 cattle, comprising 14 calves, 33 juveniles, and 181 adults. Three tick genera (i.e., Amblyomma, Hyalomma, and Rhipicephalus, including the Boophilus sub-genus) and 11 species were identified. The most prevalent species was Rhipicephalus (Boophilus) decoloratus (41.4%), followed by Rhipicephalus (Boophilus) annulatus (15.4%), Rhipicephalus guilhoni (12.0%), Rhipicephalus (Boophilus) geigyi (7.6%), Hyalomma truncatum (7.4%), Amblyomma variegatum (6.3%), Rhipicephalus simus Group (4.0%), Rhipicephalus turanicus (1.2%), Rhipicephalus sanguineus (0.3%), Hyalomma rufipes (0.2%), and Rhipicephalus lunulatus (n = 1). Mean tick loads recorded were relatively high (22 +/- 1.4), in spite of the practice of hand removal of ticks traditionally undertaken by the Fulani pastoralists in the area. Calves bore a significantly lower tick burden than adults (p = 0.004). Rhipicephalus (Boophilus) microplus was not found in the area, suggesting that the eastbound expansion of this tick species in West Africa, has not yet reached central Nigeria. Conclusions: This study ascertained the presence of a broad variety of cattle tick species, most of which are of veterinary importance. The presence of each tick species is correlated with the potential occurrence of tick-borne pathogens and suggestions for tick control in the area are considered. Results should assist the diagnosis of related TBDs in cattle as well as the strategic planning of cost-effective tick control.