Detection of Mycoplasma mycoides subspecies mycoides in tissues from an outbreak of contagious bovine pleuropneumonia by culture, immunohistochemistry and polymerase chain reaction

Postmortem observations of 37 cattle from an outbreak of contagious bovine pleuropneumonia (CBPP) in north Italy in 1993 were made at the abattoir, wh ere samples of lung and tracheobronchial lymph node tissues were taken for culture and identification of Mycoplasma mycoides subspecies mycoides (MmmS C), immunohistochemistry with the peroxidase anti-peroxidase (PAP) system, and molecular detection by the polymerase chain reaction (PCR) amplificatio n of specific DNA from MmmSC. Nasal swabs were also taken for testing by PC R. Lung pathology typical of CBPP was observed in 38 per cent of the animal s, and MmmSC was isolated from 19 per cent. DNA of MmmSC was detected by PC R in 64 per cent of lung samples and 35 per cent of the nasal swabs. Staini ng of lung tissue and lymph node tissue by PAP was positive in 27 per cent and 30 per cent of cases, respectively, and was a useful back-up test. Thes e results suggest that PCR amplification from lung tissue may be used as a rapid and accurate confirmatory test for cases with pathology resembling CB PP.