Different distribution of antimicrobial resistance genes and virulence profiles of Staphylococcus aureus strains isolated from clinical mastitis in six countries

作者：Valentina Monistero, A. Barberio, Filippo Biscarini, Paola Cremonesi, Bianca Castiglioni, H.U. Graber, Enriqueta Bottini, Alejandro Ceballos-Márquez, Volker Kroemker, Inge-Marié Petzer, C. Pollera, Carlos Santisteban, Marcos Veiga dos Santos, V. Bronzo, Renata Piccinini, Re G, Monia Cocchi, P. Moroni · 发表于：Journal of Dairy Science · 年份：2020 · DOI：10.3168/jds.2019-17141 · 被引用次数：59 · 研究领域：Milk Quality and Mastitis in Dairy Cows、Antimicrobial Resistance in Staphylococcus、Probiotics and Fermented Foods

Staphylococcus aureus is recognized worldwide as one of the main contagious mastitis agents in cattle and can express a set of antimicrobial resistance genes and virulence-associated genes that explain the wide range of outcomes of intramammary infections. Staphylococcus aureus strains are heterogeneous: their different resistance and virulence patterns, associated with host-level factors and treatment factors, are related to the severity of infection. The aim of this study was to determine phenotypic antibiotic susceptibility, occurrence of selected antimicrobial resistance genes and other virulence genes in 93 S. aureus strains isolated from clinical mastitis in 6 countries: Argentina, Brazil, Germany, Italy, the United States (New York State), and South Africa. These isolates were tested against a total of 16 drugs (amoxicillin-clavulanate, ampicillin, cefazolin, cefoperazone, cefquinome, enrofloxacin, erythromycin, gentamicin, kanamycin, lincomycin, oxacillin, penicillin, rifampin, spiramycin, sulfamethoxazole/trimethoprim, tylosin) by minimum inhibitory concentration (MIC) assay, and examined for the presence of 6 antibiotic-resistance genes (blaZ, mecA, mecC, ermA, ermB, ermC) and 6 virulence-associated genes (scn, chp, sak, hla, hlb, sea) via PCR analysis. The phenotypic results of this study revealed the presence of 19.4% penicillin-resistant strains, whereas 22.6% of the strains were classified as having resistance (5.4%) or intermediate resistance (17.2%) to erythro...