Trypanosome infection rate of Glossina pallidipes and trypanosomosis prevalence in cattle in Amaro Special District of Southern Ethiopia

Abstract

The survey was conducted in Amaro Special District, Southern Ethiopia in 2010. It was initiated to determine the trypanosome infection rate, population density of Glossinaspecies and prevalence of trypanosomosis in cattle. Glossina pallidipes was the only species of tsetse found in the study area during the study period. A total of 202 flies were dissected. The overall infection rate of G. pallidipes was 6.93%, among which 1 (0.49%) was male and 13 (6.43%) female flies. The prevalence was significantly higher (c2 = 99.82; P = 0.00) in female flies than male flies. In determination of tsetse flies population density, flies were trapped using baited stationary traps, and other biting flies were estimated in relation to altitude levels and vegetation types. Higher proportion of tsetse flies was caught in the riverine vegetation type followed by savanna and bush areas. Blood samples from 561 randomly selected cattle of both sex and different age groups were collected and examined with conventional haematological and parasitological techniques. Out of the total examined animals, 74 (13.19%) cattle were infected with trypanosomes. Most of the infections were due to Trypanosomacongolense (78.37%) followed by Trypanosoma vivax (12.13%), mixed infections of T. congolense and T. vivax (8.1%) and the rest were Trypanosoma brucei (1.35%). There was no statistically significant difference (P > 0.05) in infection between male and female, and altitude levels. Mean packed cell volume (PCV) value of parasitaemic and aparasitaemic animals was significantly (P < 0.05) different. Diagnosis of trypanosomosis in tsetse or domestic livestock is a basic requirement for epidemiological studies as well as for planning and implementing control operations. Therefore, the results of this study should be used to define the strategy of disease control in places where tsetse and trypanosomosis challenge were reported. Key words: Cattle, apparent fly density, Glossina pallidipes, Infection rate,Trypanosomosis, Southern Ethiopia.