Prevalence and impact of bovine trypanosomiasis in Mayo Rey division, a Soudano-Sahelian zone of Cameroon

Abstract

For several years, pastoralists in Mayo Rey division have reported the presence of trypanosomiasis within their herds, and have used trypanocides in the complete absence of laboratory diagnosis. This present study aimed to establish the prevalence of trypanosomiasis and its impact on local cattle. A parasitological survey was carried out in 24 herds for a total of 270 cattle selected and followed-up for a period of one year. Blood samples were collected aseptically and screened using the Buffy coat technique, and the packed cell volume (PCV) was measured. The results showed that 149 animals were found infected with trypanosome at least once during the four follow-ups, corresponding to an annual prevalence and incidence rates of 55.2 and 31.9%, respectively. The risk of bovine trypanosomiasis was higher in the rainy season. Three species of trypanosome were identified: Trypanosoma congolense, Trypanosoma brucei and Trypanosoma vivax. T. congolense was the most abundant species. The PCV was significantly higher for mixed and single infections with T. vivax. Analyses have shown that cattle breed and age group affect significantly the prevalence of trypanosomiasis. The effect of trypanosomiasis on weight loss was noticeable, but significant in the rainy season only. This study has established the prevalence and the endemicity of trypanosomiasis in the Mayo Rey division; it suggests that tsetse flies and other mechanical vectors may be abundant in the zone and raise the need for entomological investigations. Key words: Cattle, trypanosomiasis, Buffy Coat Test, packed cell volume, Soudano-Sahelian region, Cameroon.