Immunofluorescence Technique for Detection of Mycoplasma Hvopneumoniae in Swine Lungs'

Direct and indirect immunofluorescence techniques and a culture method were compared for detection of Mycoplasma hyopneumoniae in lungs of experimentally infected swine. Pneumonic lungs were obtained fiam SPF pigs that had been exposed by contact 6 to 7 weeks previously to other SPF pigs which had been inoculated with the organism. A good association was found between isolation of M. hyopneumoniae, positive immunofluorescence test results and presence of macroscopic or microscopic lesions typical of mycoplasmal pneumonia of swine. Direct and indirect immunofluorestence tests were equally efficient for detection of M. hyopneu,noniae in sections of lung. An azo dye counterstain reduced nonspecific fluorescence and provided a good color contrast without reducing sensitivity of the indirect immunofluorescence test.