Identification of MRSA isolated from bovine epidemic in Xinjiang and spa polymorphism genotyping

ObjectiveThe aime of the study was to study epidemiological characteristics of methicillin-resistant Staphylococcus aureus(MRSA)isolated from bovine in Xinjiang,and provide reference basis for effective prevention and control of dairy cows mastitis and endometritis in Xinjiang.MethodDifferential culture,biochemical identification and drug sensitive test were applied to identify MRSA,and X region of spa gene from MRSA epidemic isolate in Xinjiang was amplified. The sequencing results were submitted to spa genotype database(http://www.ridom.de/spaserver/)for spa polymorphism genotyping.ResultSeventy-one S. aureus isolates were selected from two hundred and twenty-one sam-ples. Among them,bacteriostatic diameter of eight strains for oxacillin was less than 10 mm. PCR amplification was con-ducted with mecA primer,13 strains were positive,the detection rate of MRSA were 18.3%. Four spa genotypes were de-tected:t779,t2883,t13751 and t1939. Five strains were t779(r08),four strains were t2883(r07-r23-r21-r17-r34),two strains were t13751(r07-r23-r12-r21-r17-r12)and two strains were t1939(r07-r23-r02-r34). In another word,t779(r08) was the predominant spa genotype among MRSA epidemic isolates in Xinjiang.ConclusionMRSA is distributed in different regions of Xinjiang,and its drug resistance changes constantly. t779(r08) is the predominant spa genotype among MRSA epidemic isolates in Xinjinag.