POLYMERASE CHAIN REACTION-BASED DIAGNOSIS OF MOLLICUTE INFECTION OF COMMERCIAL ANIMAL SERA

A total of 72 commercial animal sera were assayed for mollicute infect ion by a polymerase chain reaction (PCR)-based detection method and by four classical detection methods. The methods included microbiologica l assay by inoculation onto agar and into broth, DNA staining of an in dicator cell line with 4',6-diamidino-2-phenylindole dihydrochloride ( DAPI) fluorochrome, enzyme-linked immunosorbent assay (ELISA) and aden osine phosphorylase (AdoP) screening. Mollicutes were detected in 2 of the 72 sera assayed. The species isolated was Acholeplasma laidlawii in both cases. When detection methods were compared, PCR, microbiologi cal culture and DNA staining were perfectly concordant. ELISA and AdoP detection produced false-negative results for 1 of the 2 infected ser a each. False positive results appeared in 1 of the 70 mollicute-free sera with ELISA and in 16 of the 70 with AdoP detection. It was conclu ded that the PCR-based detection method is a useful tool in addition t o current methods of detection of mollicutes in animal sera, with rega rd to reliability, sensitivity, specificity and time.