Microscopic examination of haemoparasites and the first molecular detection of Theileria equi in horses in Myanmar

The study aimed to determine the prevalence of blood parasites in horses and identify risk factors and molecular detection of piroplasm species (Theileria equi and Babesia caballi) of horses in Myanmar. Blood samples (n = 302) were collected from five regions of Myanmar. Blood smears were screened for presence of piroplasms. Samples positive for piroplasms were subjected to molecular identification using primers specific to the small subunit ribosomal RNA (SSU rRNA) of piroplasms. The overall prevalence of blood parasites (piroplasms, Trypanosoma spp., and microfilaria of Setaria equina) was 30.8% (93/302). The prevalence of piroplasms, Trypanosoma spp., and microfilaria of S. equina, were 22.5% (68/302), 8.3% (25/302), and 2.3% (7/302), respectively. Samples from Yangon (35.0%) and Mandalay (35.0%) showed the highest prevalence, followed by Northern Shan State, Ayeyarwady, and Nay Pyi Taw (33.9%, 25.0% and 24.6%, respectively). The hypothesized factors (age, sex, and breed) showed no significant association (p > 0.05) with the overall occurrence of blood parasites. Although no significant association (p > 0.05) was found between blood parameters (WBCs, RBCs, Hb, and HCT) and the presence of blood parasites, the negative group had a larger WBC count than the positive group. Molecular characterization of piroplasm of two obtained sequences confirmed Theileria equi. This is the first report on microscopic and molecular detection of T. equi in horses in Myanmar, and the findings provide baseline information for blood parasites in horses.