Comparison of indirect immunofluorescence (IIF) and enzyme-linked immunosorbent assay (ELISA) in detecting Babesia bigemina infection in cattle.

An indirect immunofluorescence test (IIF) and an enzyme-linked immuno-sorbent assay (ELISA) were standardised to investigate the prevalence of bovine babesiosis caused by Babesia bigemina in experimentally and naturally infected bovids. Both IIF and ELISA detected antibodies to B. bigemina 7 days after experimental infection with 87.5% and 100% sensitivity, respectively. The IIF results indicated that a titre greater than 1:64 was a reliable indicator of B. bigemina infection. Serological study of 214 serum samples collected from Boophilus microplus infested cattle from the State of Orissa revealed 33.6% overall seroreactivity by ELISA, whereas IIF recorded 9.4%. Both IIF and ELISA showed some degree of cross-reactivity between Indian (Izatnagar) and Mexican strains of B. bigemina.