Comparative evaluation of real-time polymerase chain reaction, conventional PCR and microscopy for detection of Babesia bigemina in bovines of Punjab (India)

Babesia bigemina is a major cause of bovine babesiosis, an economically devastating tick-borne disease that needs timely diagnosis for precise treatment. In present investigation, the detection efficacy of real-time PCR (qPCR) in comparison to conventional PCR and microscopy targeting 18 S ribosomal gene was evaluated on 95 bovines (70 cattle and 25 buffaloes) suspected for babesiosis. Real-time PCR was standardized with the 10-fold serial dilutions in duplication of the given positive control (2 × 10 6 copy number) ranging from 10 6 to 10 0 copy number/µL and mean Ct value of each dilution was taken to extrapolate the curve. The samples with Ct value 36.92 of 10 copy number/µL were considered as positive. Out of 95 samples, 5 (5.26%), 21 (22.10%) and 49 (51.58%) positive by microscopy, conventional PCR and real-time PCR were in corresponding range of > 10 6 -10 4 , 10 4 -10 3 , and 10 3 -