Epidemiological study of bovine trypanosomosis and potential vectors of African Animal Trypanosomosis in North-East Benin.

The socio-economic impact of African Animal Trypanosomosis (AAT) makes it one of the major constraints to livestock development in Africa. Thus, in order to study the epidemiology of trypanosomosis in cattle, parasitological and entomological surveys were conducted. The objective of this study is to evaluate the prevalence of bovine trypanosomosis associated with entomological survey in cattle farms in North Benin. To this end, samples were taken from 823 cattle of the Borgou, Goudali, Yakana, Azawak, Zebu and mixed breeds. Microscopic examinations of blood smears stained with 10 % Giemsa gave an overall prevalence of 19.7 % (162/823). This prevalence was high in the crossbreeds (28.1 %) compared to the other breeds. Three species of trypanosomes were identified with a predominance of T. vivax (82.6 %) followed by T. congolense (9.8 %), T. brucei (2.8 %). Mixed infections (5.7 %) were also observed. The mean hematocrit ranged from 25.89 ± 5.46 to 30.31 ± 4.13 in the animals collected. Entomologically, the capture was done with Vavoua type monoconical traps placed in five different biotopes. Collection, sorting and identification revealed two species of tsetse (Glossina p. gambiensis and Glossina morsitans submorsistans). The overall Apparent Density per Trap (ADT) per day recorded was 0.66 flies with a variation from 0.16 flies at the SVD farm to 1.11 flies in the streams/lowlands. These results show that the risk of infection of animals in the environment remains high and can compromise cattle breeding. Therefore, control measures combining the vector, parasite and host must be taken to preserve animal health in Benin.