By using RT-PCR to test two suspected mycoplasma bovis pneumonia swab samples collected from the nose of a cow on a farm in Xichang,the result shows that both two samples enlarge and increase a DNA fragment with participated size(300bp).By purifying and recovering it,cloning it and testing its order,the result shows that the homology of two samples with the 16SrRNA series of mycoplasma bovis in GenBank(GenBank passwords: AF332754)is 99%.Mycoplasma bovis is likely to be one of the reasons to cause cow's pneu...