[Objective] To understand genotyping characteristics, genetic variation and the distribution of virulence factors of Staphylococcus aureus isolated from rabbits in Sichuan area.[Method]Forty-one S.aureus strains were isolated from rabbits in Sichuan area.The strains were identified for femB gene specifity.Methicillin-resistant S.aureus(MRSA) were screened out.Thirteen common virulence genes were detected using PCR.Genotyping characteristics were studied by using multilocus sequence typing (MLST) and pulsed field gel electrophoresis (PFGE).[Result]There were 31 MRSA strains out of 41 S.aureus strains, and the detection rate was 75.61%.Totally nine virulence genes were detected, nuc, hla, eta and clfA genes existed in all strains, and the positive detection rates of sea, sec, see, hlb and PVL genes were 9.7%, 85.4%, 80.5%, 90.2% and 7.3%, respectively.MLST results showed that 41 S.aureus strains belonged to two sequence types (ST398, ST3320) and one clonal complex CC398.ST398 was the preponderant sequence type, and the proportion was 97.6%.PFGE analysis divided 41 S.aureus strains into 18 banding types, whereas strains from different regions had low variation in banding patterns.[Conclusion] S.aureus strains isolated from rabbits in Sichuan area have high carrying rates of virulence factors, and therefore are potential security risk to rabbit farming industry.The genotyping analysis indicates that the prevalent strains of S.aureus isolated from parts of Sichuan Province have low genetic variation, and there are close genetic relationships among different strains.%[目的]研究四川部分区域兔源金黄色葡萄球菌Staphylococcus aureus的基因型总体结构特征、遗传变异以及毒力因子的分布情况.[方法]从四川地区分离41株兔源金黄色葡萄球菌,鉴定femB基因特异性, 进行耐甲氧西林金黄色葡萄球菌(Methicillin-resistant S.aureus, MRSA)筛选,并通过PCR法检测13种常见的毒力基因,采用多位点序列分型(Multilocus sequence typing,MLST)和脉冲场凝胶电泳(Pulsed field gel electrophoresis,PFGE)确定基因型特征.[结果]41株金黄色葡萄球菌中共检测出MRSA 31株,检出率为75.61%;共检出9种毒力基因,其中nuc、hla、eta和clfA在所有菌株中均存在,而sea、sec、see、hlb和PVL的阳性检出率分别为9.7%、85.4%、80.5%、90.2%和7.3%.MLST 分型结果显示,41株金黄色葡萄球菌只存在2种序列型(ST398、ST3320)和1个克隆群CC398,其中ST398为优势序列型,所占比例为97.6%.PFGE将41株金黄色葡萄球菌分为18个基因型,但不同区域间的基因型条带差异较小.[结论]四川调查区域兔源金黄色葡萄球菌毒力因子携带率较高,其对家兔的养殖业存在较大的安全威胁;分型分析说明四川部分区域金黄色葡萄球菌的主要流行菌株遗传变异程度小,菌株间亲缘关系较近.
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