EPIDEMIOLOGY OF GASTROINTESINAL PARASITES OF HIROLA (BEATRAGUS HUNTERI, SCLATER, 1889) AND LIVESTOCK IN SOUTHERN KENYA

Abstract

The rapid decline in the population of Hirola over the last century has caused great concern among conservationists. Together with factors such as predation, drought, habitat loss, competition for resources with livestock and poaching, diseases including parasitoses have been implicated in this sudden decline. Parasite driven declines in wildlife have become increasingly common and pose significant risks to natural populations. A study on the epidemiology of gastrointestinal parasites of Hirola (Beatragus hunteri) was conducted between September 2009 and March 2010. The main goals were to determine the prevalence and intensity of gastrointestinal parasites in Hirola and livestock, to investigate the influence of area, season and host characteristics of age and sex on prevalence and intensity of gastrointestinal parasites in Hirola and livestock and to determine the level of aggregation of gastrointestinal parasites in Southern Kenya. The results showed that both Hirola and livestock were infected by a wide variety of strongyles, trematodes, cestodes and coccidia. These parasites differed significantly in terms of prevalence and intensity in the hosts with strongyles being the most prevalent (67.97%) and coccidia having the highest intensity of infection (537.78 oocysts per gram ±135.59SE). Season and age were found to be the main factors influencing infection patterns in both Hirola and livestock with significantly higher prevalence (χ2 = 9.928; df = 1, p = 0.002) and intensity (F1, 409 = 23.36; p = 0.001) were being recorded during the wet than dry season and higher prevalence being observed among the young than adult animals. Generally, females had higher prevalence but slightly lower intensities of infections than males though the difference was not statistically significant (prevalence: χ2 = 0.023; df = 1, p = 0.878; intensity: F1, 409 = 0.010; p = 0.921. Apparently, Hirola in Ishaqbini had slightly higher prevalence and intensity than those in Tsavo with contrary observations being made among cattle. The results also indicated high levels of aggregation of individual parasite taxa among the hosts (k<1). The features of these results showed the need to target the young Hirola (or calves) in the future control and management of gastrointestinal parasites at the Hirola-livestock interface in Southern Kenya as these appeared to be at a higher risk. This should consider the seasonal patterns influencing prevalence and intensity of the parasites. In future, a study to develop a checklist of gastrointestinal parasites of both Hirola and livestock in Southern Kenya is also recommended in order to better understand the transmission of gastrointestinal parasites between the two herbivores.