Molecular Detection and Characterization of Trypanosomes Infecting Traditionally Managed Cattle in the Tropic Warm Sub-Humid Zone of Nigeria

Traditionally managed cattle constitutes the main source of animal protein to humans in Nigeria. However, seasonal migration in search of pasture exposes them to several vector-borne infections such as the African Animal Trypanosomosis (AAT), which limits their productivity. In this study, blood samples from 130 cattle in Plateau and Nasarawa states collected from May to June, 2021 were examined by the Polymerase Chain Reaction (PCR) and sequencing methods to determine the prevalence of pathogenic trypanosomes. Overall, the DNA of T. vivax was detected in 19 out of the 130 (14.6 %) samples examined by the PCR. However, using the micro-hematocrit centrifugation technique, motile haemoparasites were detected in only six (4.6 %, confidence interval [CI] 0.5—6.9 %) of the samples. The higher prevalence of T. vivax was recorded in samples sourced from the abattoir than in samples submitted from the field in Plateau state (16.7 % versus 11.5 %). However, the reverse was the case in Nasarawa state (2.9 % versus 37.5 %). The difference in prevalence of T. vivax between the abattoir and field samples was significant (P = 0.009) in Nasarawa state, but not in Plateau state (P = 0.55). The mean PCV (Packed Cell Volume) of the trypanosome infected animals was lower than that of the non-infected animals, but the difference was not significant (P = 0.29). The internal transcribe spacer region (ITS) nucleotide sequences of T. vivax generated in this study were 100 % identical to each other and formed a monophyletic cluster with the sequences of T. vivax from different countries in the GenBank. AAT remains a major constraint to profitable cattle production and food security in Nigeria and deserves more attention.