Comparison between Enzyme-Linked Immunosorbent Assay, Disc Film Inhibition and Complement Fixation tests for the diagnosis of Mycoplasma bovis

Abstract

A total of 1300 bovine field sera was tested by the Indirect ELISA, Complement Fixation (CF) and Disc Film Inhibition (DFIT) Tests, for the detection of Myco-plasma bovis infections by the determination of circulating antibodies in naturally infected cattle. ELISA showed the highest specificity (96%) for detection of antibody against M. bovis, when ELISA OD ³ 0.900 was considered as positive, testing negative sera in DFIT, and considering CF titres of 1/40 as positive. For sensitivity evaluation, the highest sensitivity of ELISA (90%) was obtained considering ELISA OD ³ 0.600 as positive, testing sera positive in DFIT, and considering CF titres of 1/40 as negative. The ELISA proved to be a sensitive and specific test for Mycoplasma bovis serodiagnosis. The immunoglobulin classes measured by each of the tests under study are discussed.