The first molecular detection and genetic diversity of Babesia caballi and Theileria equi in horses of Gansu province, China

Equine piroplasmosis, caused by Theileria equi and Babesia caballi, is an economically important tick-borne disease worldwide. In the current study, 242 blood samples were randomly collected from horses in Zhangye city of Gansu province, China. The presence and genetic diversity of piroplasms were evaluated with a nested PCR assay, gene sequencing and phylogenetic analysis. The results showed that seventy-five (31.0%) samples were positive for piroplasms. Sequences analysis showed that seventy-three (30.2%) were positive for T. equi, and seven (2.9%) for B. caballi, five of which (2.1%) were infected with T. equi and B. caballi. Phylogenetic analysis revealed two T. equi genotypes (C and E) and one B. caballi genotype (A). The molecular epidemiological and genetic diversity results provide important epidemiological data for control of equine piroplasmosis caused by T. equi and B. caballi in China.