Diagnosis of contagious caprine pleuropneumonia by detection and identification of Mycoplasma capricolum subsp. capripneumoniae by PCR and restriction enzyme analysis

Abstract

Contagious caprine pleuropneumonia (CCPP), one of the most serious and dramatic diseases of goats, is caused by Mycoplasma capricolum subsp. capripneumoniae (M. capripneumoniae). This organism is very difficult to isolate and to correctly identify. In a previous report we described a method for the rapid detection and identification of M. capripneumoniae. This method is based on a PCR system by which a segment of the 16S rRNA gene from all mycoplasmas of the M. mycoides cluster can be amplified. The PCR product is then analyzed by restriction enzyme cleavage for the identification of M. capripneumoniae DNA. This system has now been further evaluated with respect to specificity and diagnostic efficacy for the identification and direct detection of the organism in clinical material. Identification by restriction enzyme analysis of amplified DNA from mycoplasmas of the M. mycoides cluster was verified for 55 strains, among which were 15 strains of M. capripneumoniae. The PCR was applied to clinical samples from the nose, ear, pharynx, pleural fluid, and lung tissue containing M. capripneumoniae or other mycoplasmas. As expected, mycoplasmas belonging to the M. mycoides cluster could be detected by the PCR. Restriction enzyme analysis of the PCR products could then be applied for the identification of M. capripneumoniae. Clinical samples and cultures containing M. capripneumoniae were dried on filter paper, to try an easier sample transport method, and were tested by PCR. M. capripneumoniae DNA could be detected in the dried specimens, but the sensitivity of the PCR test was reduced.