High prevalence of Trypanosoma spp. and apparent trypanocidal drugs inefficacy in cattle in Al Radom National Park, Sudan

Trypanosomosis is a major infectious disease affecting cattle in Sudan. In South Darfur, data on cattle trypanosomosis has been limited since the Darfur civil war (2003-2007). This study assessed the prevalence and distribution of Trypanosoma spp. in cattle in the tsetse fly endemic Al Radom National Park, and collected questionnaire data on trypanocide use and apparent efficacy. Blood from 509 cattle across four regions was analysed. Of these, 3.1%, 19.8% and 35.8% tested positive for trypanosomes by microscopy, buffy coat technique and PCR, respectively. At the regional level, prevalence was 50.0%, 42.9%, 27.3% and 22.9% in Al Radom Livestock Market, Kafindibei, Al Radom town and Murayrayah, respectively. Trypanosoma congolense savannah (15.7%), Trypanosoma vivax (9.6%), Trypanosoma brucei (0.8%) and Trypanosoma theileri (13.4%) were identified. Prevalence was significantly correlated with region and age (P < 0.05). Older cattle showed significantly higher prevalence (44.7%) than 1-3 years old (29.7%) and < 1 year old cattle (22.7%). Most cattle (86.8%) had received trypanocides within 30 days before sample collection, mainly diminazene aceturate, either alone or combined with isometamidium chloride and/or quinapyramine. Despite treatment, 30.7% were Trypanosoma-positive by PCR. In conclusion, trypanosomes are prevalent in Al Radom National Park, even in treated cattle, indicating apparent drug inefficacy, which requires further research and control measures.