Application of culture and polymerase chain reaction (PCR) methods for isolation and identification of Mycoplasma synoviae on broiler chicken farms

Mycoplasma synoviae (M. synoviae) is a major worldwide poultry pathogen that causes serious economic losses in the poultry industry. This study was designed to detect M. synoviae through culture isolation and polymerase chain reaction (PCR) assay to demonstrated the involvement of M. synoviae infection in trachea and the lung/air sac samples taken from commercial broiler chicken farms in 3 main provinces of Iran (Tehran, Markazi and Qazvin), with clinical signs of the disease. Total of 43 samples were cultured in PPLO broth media supplemented for M. synoviae isolation. The bacteria DNAs were extracted by phenol/chloroform method and the PCR assay amplifying the conserved region of 16S rRNA gene was applied for the detection of Mycoplasma genus in 163bp fragment and M. synoviae in 207bp fragment from culture as same as in clinical samples. Of the 43 swabs 28(65.1%) yielded one of the potentially pathogenic mycoplasmas evaluated for using PPLO agar culture diagnostic method, and 33(76.8%) yielded one of the potentially pathogenic Mycoplasmas evaluated for using Mycoplasma genus PCR as diagnostic method, and 24(55.9%) of the swabs yielded M. synoviae for using M. synoviae PCR as diagnostic method. In this study we had observed the highest quantity of M. synoviae infections in broiler chicken with PCR test. In conclusion, PCR is a more rapid, effective, sensitive and inexpensive method than the standard culture technique, that could be used as an alternative method for traditional culture and showed the real number of the M. synoviae contaminated broiler chicken farms.