Abstract:The aim of this work was to investigate the contamination, virulence characteristics, and drug resistance of milk-derived Staphylococcus aureus in the Shihezi region. The quantitative detection of S. aureus was carried out on 24 retail milk samples, and the presence of nuc, 16S rRNA, and virulence genes was confirmed by polymerase chain reaction (PCR). The Kirby–Bauer method was used to test the sensitivity of S. aureus to 12 antibiotics. A total of 55 suspected isolates of milk-derived S. aureus were obtained, and 20 isolates were positive in nuc and 16S rRNA gene PCR amplification assays. The virulence gene detection revealed five (5/20; 25%) S. aureus isolates carrying virulence genes, [three isolates carrying Coa (3/5; 60%), one isolate carrying Sei (1/5; 20%), and one isolate carrying Sea + Sec + Coa (1/5; 20%)]. Nineteen out of 20 isolates of S. aureus were found to be resistant to one or more of the tested antibiotics by the disk diffusion method. All the 19 isolates were sensitive to imipenem and chloramphenicol. This paper provides important reference data for rational application of antibiotics in clinical practice and animal breeding and provides the theoretical basis for the risk assessment of harmful S. aureus strains in dairy products.
