Detection of Mycoplasma gallisepticum by PCR and DNA Probe Hybridzation

A pair of 25 base primers were designed and synthesized according to the nucleotide fragment(fMG 2) sequence of Mycoplasma gallisepticum. The primers were applied to amplify Mycoplasma gallisepticum DNA by PCR and expected amplification of a 732 bp product was demonstrated by ethidium bromide staining of 1.5% agarose gel electrophoresis,its sensitivity to be 1 pg without the control strain DNA to be amplified.Thereafter the PCR product was used as a probe labelled with DIG 11 dUTP via random primer labelling to hybridize with the DNA above. The Dot blot assay suggested that the probe hybridized with DNA of Mycoplasma gallisepticum but not with that of negative control strains,its sensitivity to be 100 pg.The further detection to naturally infected chickens showed that the two methods developed in this study had a high sensitivity and specificity,which could be applied to detection of early and latent infection of Mycoplasma gallisepticum.