Summary: | <i>Staphylococcus</i> spp. is an important mastitis-inducing zoonotic pathogen in goats and is associated with antimicrobial resistance (AMR). The objectives of this study were to determine the prevalence and composition of staphylococci in individual mammary secretion (MS) samples of clinically healthy goats and to evaluate the phenotypic AMR pattern and the presence of methicillin resistance in the <i>Staphylococcus</i> spp. strains. <i>Staphylococcus</i> spp. isolates (<i>n</i> = 101) from the MS samples (<i>n</i> = 220) were identified to species level using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The antimicrobial susceptibility testing included a disk diffusion assay and the determination of the minimum inhibitory concentrations (MIC) of resistant strains (<i>n</i> = 46). Presumptive methicillin-resistant strains (<i>n</i> = 9) were assessed for the presence of <i>mecA</i>, <i>mecC</i> and <i>SCCmec</i>/<i>orfx</i> genes. <i>Staphylococcus</i> spp. isolates were recovered from 45.9% of the MS samples, of which, 72.3% was identified as coagulase-negative staphylococci (CoNS), with the remaining being <i>Staphylococcus aureus</i>. CoNS and <i>S. aureus</i> were most commonly resistant to ampicillin (56.2% and 57.1%, respectively), penicillin (26.0% and 39.3%, respectively), amoxicillin (26 % and 25 %, respectively) and cephalexin (12.3% and 25%, respectively) in the disk diffusion method. CoNS exhibited a broader AMR pattern and a higher percentage of resistant strains than <i>S. aureus</i> in the disk diffusion and MIC methods. Of the nine oxacillin- and cefoxitin-resistant strains, three <i>S. aureus</i> and five CoNS strains carried the <i>mecA</i> gene and, thus, were identified as methicillin-resistant. The <i>mecC</i> gene was not found in any of the studied strains. The presence of AMR and methicillin resistance in caprine <i>S. aureus</i> and CoNS poses a concern for animal and public health.
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