Genetic Characterisation of Trypanosoma vivax Isolates from Cattle in the Tsetse Belt of Kogi State Using Molecular Markers

This study provides the first genetic characterisation of Trypanosoma vivax isolates from cattle in the tsetse belt of Kogi State, located in Nigeria's North Central geopolitical zone, using molecular markers to define population structure and geographic variation. T. vivax is the most prevalent trypanosome species in West African cattle and is responsible for significant mortality and production losses, yet its genetic diversity and population structure in Nigeria have been poorly defined, limiting understanding of spread dynamics and potential drug resistance origins. Using a cross-sectional molecular epidemiology design, blood samples were collected from 200 T. vivax-positive cattle identified by buffy coat microscopy across six local government areas in the tsetse-endemic forest-savanna transition zone of Kogi State. DNA was extracted from buffy coat fractions, and T. vivax was confirmed by ITS1 PCR. Genetic diversity was assessed by microsatellite typing at eight loci and by sequencing of the cathepsin-L-like cysteine protease gene. Population genetics metrics including expected heterozygosity, allelic richness, and linkage disequilibrium were calculated. The study fills a foundational molecular epidemiology gap for T. vivax in the Middle Belt. Findings revealed high genetic diversity and predominantly clonal population structure, with evidence of geographic clustering consistent with restricted gene flow between northern and southern Kogi populations. Keywords: Trypanosoma vivax, molecular characterisation, genetic diversity, Kogi State, trypanosome.