Differentiation between field and vaccinal strains of Mycoplasma gallisepticumis important for the epidemiology of the disease. Real time PCR assay was applied to detect MG and further tested by mgc2 rt-PCR for F, 6/85 and TS-11 strains. Twenty four farms were positive for MG Out of the 50 farms, from which 12 were positive for F strain and 5 were positive for 6/85 strain, while 7 farms were MG positive but negative for live vaccine rt-PCR. DNA nucleotide sequencing for 20 positive cases for mgc2 gene confirmed the rt-PCR results, some point mutations were found in the isolated strains and grouped the sequenced samples into 4 groups (F, 6/85 and two field strain groups named field group A and B).