Isolation Of Contagious Caprine Pleuropneumonia Pathogen And Molecular Characteristic Analysis Of China Strains

CCPP is a goat disease of great concern in Africa and Asia and is included in the B list of communicable animal diseases of the Office International des Epizooties.CCPP was first described at the end of the last century and was shown to be caused by M. capricolum subsp. Capripneumoniae in 1976 by MacOwan and Minette. More than 30 countries have declared that they have detected CCPP, but the organism has been isolated from goats in only 11 countries.In this study,a strain of mycoplasma was isolated successfully from the lung of a goat suspected of being affected by contagious caprine pleuropneumonia, after clone and purification for three times, tested by biochemistry,observed by electron microscope,PCR and REA,genome distinguish. The result showed SD3 isolation belonged to the member of Mycoplasma capricolum subsp. Capripneumonia, After inoculating two goats by trachea using SD3 isolation, one of two had clinic symptom , the temperature raised to 41.5℃. IgG and IgM showed a high raising, the change of IgG was consistent with clinic representations. We found the lung of the goat had serious pathological changes after autopsy, again isolated the pathogen from the lung.The classify status of the CCPP pathogeny existed for two different mycoplasma between china (M mycoides subsp. Capri, MmC) and the OIE (Mccp). So we identified 4 China separated strains by molecular method, to confirm the really status of them. Amplify the 4 strains DNA by 3 pairs of primer for 3 different genome fragments, then the amplified fragment was transformed into the plasmid, sequenced and analysed with six members of Mycoplasma mycoides cluster. The 4 strains PCR produce have the three fragments of 548 bp, 420 bp, and 128 bp obtained after cleavage with Pst I just like strain F38. Homology analysis of rpsG and fusA gene indicated that the 4 strains, exhibited 99.5% homology with Mccp reference strain F38, 98.9% with Mycoplasma capricolum subsp. Capricolum (Mcc) strain California Kid and only 95.4% with MmC strain ZZ. And in H2 and H2prim segment, the 4 strains have 67.4%～67.6% homology with MmC PG3, 95.1%～98.6% with Mcc strains 8601-50 and California Kid, 99.6%～99.8% with Mccp strains 97097ET,Gabes and F38.The 4 pathogeny mycoplasma, 87001,87002,367,1653, isolated from china was more closely related to Mccp than MmC. So we think that the pathogeny of CCPP in China is belong to Mccp.