Staphylococcu aureus is the most prevalent microorganism associated with mastitis in cattle. This study was designed to determine the spa types of Staph. aureus and to assess the resistance genes profile of isolated strains in dairy farms in Jordan. In total, 747 milk samples of cattle suffering from subclinical mastitis were collected from 37 dairy farms and tested for Staph. aureus. To detect antimicrobial resistance genes, all 219 strains of Staph. aureus were tested. Furthermore, 21 isolates of Staph. aureus were typed using spa typing. As a result, different proportions of resistance genes were found for Staph. aureus. High resistance genes were in tetK 100%, blaZ 99%, and tetM 97%. Moderate resistance genes were in aac(6')/aph(2'' 52%, ant(4')-Ia 48%, and ermC 41%. Low resistance genes were in ermA is 24%, aph(3')-III is 15%, and mecA is 15%. The spa typing of 21 isolates revealed six spa types, of which five were previously known. For the first time, a novel spa type (t17158) was identified as the main cause of mastitis in dairy cows in Jordan. The identification of resistance genes and spa types is helpful in determining the most effective treatments for cows and plays a significant role in reducing the transmission of pathogens.
Keywords: Staphylococcus aureus; MRSA; milk quality; public health risk; resistance pattern; subclinical mastitis.
© The Author(s) 2023. Published by Oxford University Press on behalf of Applied Microbiology International.