Trypanosoma evansi is an important haemoprotozoan parasite from the Indian context. A wide range of variations in the parasite genotype and subsequently, in disease pathogenesis have been described in the literature. The present study was designed to find out the associative genetic diversity, within the various equine isolates of T. evansi across India and the globe, based on the ITS 1 gene. A total of five equine isolates were characterized. PCR products were sequenced. A phylogenetic tree was constructed based on the maximum parsimony (MP) method with the tree–bisection– regrafting (TBR) algorithm. Indian isolates formed three haplotypes. The present isolates showed 99.06-100.00% nucleotide homology within themselves. In broader terms, present isolates were found to be phylogenetically closer isolates from Haryana. Broadly, Indian isolates of T. evansi were closely related to isolates reported from Thailand and China than those from Iran, Nigeria, and Egypt. Another remarkable finding is the close association of equine isolates from India with other isolates of family equidae and their clear divergence from isolates of T. evansi affecting other hosts from India and abroad. Vast genetic divergence was seen between the isolates suggesting of multiple distinct lineages of T. evansi amongst the Indian livestock.

Highlights

• Study comprised of characterization of equine isolates of Trypanosoma evansi from semi arid India based on ITS gene.
• Appreciable genetic diversity was noticed based on ITS gene locus.
• Marked host specific closeness was noticed between equine isolates on the phylogenetic tree.