关键词: 金黄色葡萄球菌, 分离, 鉴定, 致病性, 耐药性, 猪乳

Abstract: [Objective] The aims of the present study were to isolate and identify Staphylococcus aureus （S. aureus） strains from porcine milk in Aral City, Xinjiang Uygur Autonomous Region, and to characterize the virulence and antimicrobial resistance of the isolates.[Method] Six fresh porcine milk samples were collected from a large-scale farm in Aral City, and mannitol salt agar （MSA） was used to isolate S. aureus strains. The isolates were confirmed by phenotypic identification method and 16S rDNA sequence analysis. The biofilm formation ability of the isolates was determined. Antimicrobial sensitivity test was performed using K-B disk diffusion method. PCR assay was employed to detect the virulence and antimicrobial resistance genes.[Result]After isolation and molecular biology identification, two S. aureus strains were obtained from the milk samples, with a separation rate of 33.33% （2/6）. Both isolates had strong biofilm formation ability （+++）. The two isolates were sensitive to rifampicin and resistant to penicillin, cefoxitin, tetracycline, erythromycin, temicoxacin, clindamycin and sulfamethoxazole. Out of the five tested antimicrobial resistance genes, both isolates carried ant （4） gene and mecA gene. A total of six virulence genes were detected among the twenty tested virulence genes. Among these, both isolates carried seg, sei, hlb, fnbA and clfA genes. One isolate carried hla gene.[Conclusion]The porcine milk derived S. aureus strains in this farm had strong biofilm formation ability and carried multiple virulence and antimicrobial resistance genes, exhibiting multiple-drug resistance.

Key words: Staphylococcus aureus, isolation, identification, virulence, antimicrobial resistance, porcine milk