Molecular characterization of Trypanosoma species infection among cattle in Kwara State, North Central, Nigeria.

Animal trypanosomosis is still a major factor retarding the growth of the livestock industry in Africa, causing great economic losses and increased morbidity and mortality. There has not been a comprehensive report on the molecular characterization of Trypanosoma species in cattle in the entire Kwara State. Therefore, this study was carried out to assess the prevalence, risk factors, and molecular characterization of Trypanosoma species infecting cattle in Kwara State, North Central Nigeria. A total of 325 blood samples were collected from cattle in the three senatorial districts of the state. All samples were subjected to molecular analysis to screen for the presence of Trypanosoma species using conventional polymerase chain reaction (PCR). Positive amplicons were sequenced, and phylogenetic analysis was performed to determine genetic relationships among the positive amplicons and reference sequences retrieved from GenBank. The overall molecular prevalence of Trypanosoma infection was 9.54% (31/325). Two Trypanosoma species were observed: Trypanosoma congolense and Trypanosoma evansi. Body condition score, packed cell volume (PCV), and distance to human settlement were associated with Trypanosoma species prevalence in the multivariate logistic regression analysis. Phylogenetic analysis revealed moderate phylogenetic relationships among T. congolense isolates, which were distributed across multiple phylogenetic clusters and revealed close evolutionary relationships with isolates previously reported from Nigeria, Iraq, Japan, the UK, and other African countries. In contrast, the T. evansi isolate clustered with strains from Nigeria, Brazil, India, Pakistan, and other parts of the globe, demonstrating high phylogenetic similarity and relatively low phylogenetic relationship compared with T. congolense. This study highlights important molecular epidemiological data for understanding bovine trypanosomosis in Nigeria and accentuates the need for continuous molecular surveillance, better management practices for livestock, strategic chemotherapy, and holistic vector control programmes to reduce the burden of the disease and improve cattle productivity.