A comparative study of serological tests and PCR for the diagnosis of equine piroplasmosis

A total of 105 serum samples from endurance horses from different stables in Dubai were examined for the presence of antibodies against Theileria equi and Babesia caballi using immunofluorescence antibody test (IFAT) and competitive enzyme-linked immunosorbent assay (cELISA). A TaqMan real-time polymerase chain reaction (PCR) was used to detect DNA of piroplasms in specimens of clotted blood or EDTA blood samples of the same animals. Out of the 105 serum samples, the IFAT detected antibodies against T. equi in 35 (33.3%) cases while the cELISA gave 34 (32.4%) positive results. Eleven (10.5%) of the 105 sera were positive in the B. caballi IFAT while an additional five (4.8%) other specimens were diagnosed positive using the cELISA. The serological results showed that 13 (12.4%) horses had antibodies against both T. equi and B. caballi. The TaqMan real-time PCR detected DNA of piroplams in 33 (31.4%) samples while serological methods found antibodies in 38 (36.2%) horses.