BOVINE TICK BORNE DISEASE OCCURRENCE IN SOUTHERN RIFT VALLEY OF KENYA

Abstract

Tick borne protozoan diseases, are among the most important diseases affecting the productivity of livestock worldwide and result in high economic losses. A prerequisite for the control of these diseases is to study their epidemiology by mapping their distribution and seasonality of transmission relative to their vectors. The main objective of the study was to determine the prevalence and transmission of tick borne protozoan diseases in bovids in Southern Rift valley. The specific objectives were to determine the prevalence and distribution of tick borne protozoan diseases in three sub counties in relation to age and gender, determine the effects of temperature and humidity on vector abundance and the effectiveness of the vector control measures employed by farmers. Purposive sampling was used in site selection and a total of 196 blood serum samples were collected from 100 randomly selected farms in the three sub counties. Geimsa staining and ELISA Test techniques were employed to identify the parasites while the tick vectors were collected by flagging and identified by use of morphological features and key guides. The results showed that the overall TBDs prevalence rate by microscopy in the three sub counties was 29.6% though it varied among the sub counties, Kericho West (25%) Bureti (36%) and Bomet central having 27.47%. An overall TBDs prevalence rate of 66.84% by serology was observed and more females 116(59.18%) were infected than males 15(7.65%) but the association of gender with seropositivity was significantly indifferent (p > 0.05). Based on age bovids >1 year were more affected 126 (56.12%) compared to bovids < 1 year 70 (10.7%) and this was statistically insignificance (p > 0.05). Comparison of weather variables and vector abundance, showed that temperature was negatively correlated (r = - 0.235) while relative humidity was positively correlated (r =0.216) to vector abundance. Two tick genera (Boophilus and Rhipicephalus) were identified in the region with varying abundances. Majority of the farmers employed hand spraying (77%) in the control of tick vectors however, hand sprayed cattle (55.6%) were more affected than dipped cattle (11.2%). However the difference in effectiveness of the two methods was statistically insignificant (p > 0.05). Three tick borne diseases were diagnosed in the region and these were Theileriosis and Babesiosis The results showed that babesiosis(18.38%) was more prevalent especially in Bomet (27.47%) probably due to warm conditions, grazing system (communal) and host availability and Theileriosis was more prevalent in Kericho. It was concluded that tick borne protozoan diseases are still a problem to livestock farmers and there was a need to improve tick control efforts in the region.