Diversity of ticks and tick-borne protozoan parasites from livestock and wildebeests at the Maasai-mara wildlife- livestock interface, Narok county, Kenya.

Abstract

Wildlife-livestock interfaces are hotspots for tick-borne livestock diseases, which cause high mortalities and morbidity. Wild bovines in these interfaces play a major role in maintaining tick vectors and tick-borne pathogens. This study explored the diversity of ticks infesting blue wildebeests (Connochaetes taurinus), cattle and sheep as well as the diversity of protozoan pathogens harboured by these ticks in the Maasai Mara which is one of the wildlife – livestock interfaces in Kenya. Ticks were collected from cattle, sheep and wildebeests, identified and genetic diversity determined by amplification of Cytochrome C Oxidase subunit 1 (COI), Internal Transcribed Spacer 2 (ITS2) and 12S ribosomal DNA (12SrDNA). Protozoan pathogen diversity was studied by amplification of 18S ribosomal DNA (18SrDNA). Of the 165 ticks collected, 74 (44.8%) were Rhipicephalus evertsi and 69 (41.8%) were Rhipicephalus appendiculatus. Other species collected were Rhipicephalus pulchellus, Rhipicephalus Boophilus decoloratus and Amblyomma variegatum. All the R. appendiculatus ticks were obtained from wildebeests while R. evertsi were collected from cattle, sheep and wildebeests. Eight of the Rhipicephalus evertsi ticks from wildebeest harboured Theileria parva parasite DNA, whereas two were found to be infected by Theileria equi and one harboured Theileria ovis. Theileria parva was found in ten of the R. appendiculatus ticks while Theileria equi was found in two R. appendiculatus ticks. Phylogenetic analysis showed that both R. evertsi and R. appendiculatus were significantly similar across domestic and wild hosts, suggesting that the vectors could be shared across both wild and domestic animals. R. evertsi was present across wild and the domestic species (wildebeest, cattle and sheep) in the Maasai Mara ecosystem. Theileria species responsible for bovine (T. parva), equine (T. equi) and ovine theileriosis (T. ovis) were found harboured by both R. appendiculatus and R. evertsi warranting further studies on the specific role of these tick species in transmission of these parasites within the Maasai Mara. Two strains of Babesia parasites, with genetic similarity to B. microti and B. canis were also identified in both R. appendiculatus and R. evertsi ticks. Protozoan pathogens of zoonotic importance were not detected in either of the analysed tick species.