山羊支原体山羊肺炎亚种的分离鉴定与培养工艺改良OA

To isolate and identify Mycoplasma capricolum subsp.capripneumoniae(Mccp)in Inner Mongolia and to improve its growth concentration in liquid media,43 suspected contagious caprine pleuropneumonia(CCPP)samples were collected from Bayannur and surrounding areas of Inner Mongolia for isolation,cultivation,and morphological observation.The isolates were identified to subspecies level by gene amplification and sequence analysis.Based on initial pH adjustment and medium composition modification,the optimal conditions for enhancing Mccp growth were determined using color change unit(CCU)and polymerase chain reaction(PCR)assays.The results showed that five single colonies of Mccp were successfully isolated and purified,exhibiting typical papillary shape under an optical microscope.Sequence analysis indicated that Mccp was the primary pathogen causing goat pneumonia in the region,showing 100%homology with the Mccp strains M1601(Gansu,China),F38,and ILRI181(Kenya).Compared with the World Organisation for Animal Health(WOAH)-modified CCPP liquid medium(pH 7.6,containing thallium acetate),Mccp growth concentration was significantly higher(P<0.05)in CCPP liquid medium with an initial pH of 8.4 and without thallium acetate,reaching up to 10¹¹ CCU/mL,with an inoculation success rate increase of 20.93%.These findings demonstrate that five Mccp isolates were successfully obtained and that adjusting the initial pH of CCPP liquid medium to 8.4 and removing thallium acetate significantly enhanced Mccp growth(P<0.05),achieving a peak concentration of 10¹¹ CCU/mL and higher inoculation success.This provides a solid scientific basis for Mccp isolation,identification,and culture optimization.