Genetic diversity and antimicrobial resistance in Staphylococcus aureus and coagulase-negative Staphylococcus isolates from bovine mastitis in Minas Gerais, Brazil

Author(s)

Dorneles, Elaine M. S. ^[1] ; Fonseca, Mariana D. A. M. ^[2] ; Abreu, Juliana A. P. ^[2] ; Lage, Andrey P. ^[3] ; Brito, Maria A. V. P. ^[4] ; Pereira, Carine R. ^[1] ; Brandao, Humberto M. ^[4] ; Guimaraes, Alessandro S. ^{[1, 4]} ; Heinemann, Marcos B. ^[2]

Affiliation

^[1] Univ Fed Lavras, Dept Med Vet, Lavras, MG - Brazil

^[2] Univ Sao Paulo, Dept Med Vet Prevent & Saude Anim, Fac Med Vet & Zootecnia, Sao Paulo, SP - Brazil

^[3] Univ Fed Minas Gerais, Dept Med Vet Prevent, Escola Vet, Belo Horizonte, MG - Brazil

^[4] Embrapa Gado Leite, Nucleo Saude Anim & Qualidade Leite, Juiz De Fora, MG - Brazil

• Document type: Journal article
• Source: MICROBIOLOGYOPEN; v. 8, n. 5 MAY 2019.
• Web of Science Citations: 0

Abstract

The aims of this study were to determine the antimicrobial susceptibility profile and genetic diversity of Staphylococcus spp. isolated from dairy cows in Minas Gerais, Brazil, and to assess the relationship among the isolates' susceptibility profiles and pulsed-field gel electrophoresis (PFGE) genotypes. Seventy-nine isolates were used, including S. aureus (n = 71) and coagulase-negative staphylococci (CoNS) (n = 8). Susceptibility to 12 antimicrobial agents was performed. All Staphylococcus spp. were subjected to PFGE. Staphylococcus aureus and CoNS isolates exhibited full susceptibility only to cephalothin. The greatest percentages of resistance among Staphylococcus spp. were observed to penicillins, folate pathway inhibitors, and tetracyclines. Twelve S. aureus and four CoNS were classified as multidrug resistance strains. Percentage of MRSA was also higher among CoNS (75%), compared to S. aureus isolates (2.81%). Adopting 100% of similarity, 34 different genotypes were identified. Association of minimum-spanning tree (MST) analysis with data from municipalities, herds, methicillin-resistant S. aureus (MRSA), and resistance patterns for all isolates did not show any clustering. However, a clustering pattern of bacterial species was observed. Results from this study indicate a high frequency of antimicrobial resistance, especially among CoNS, and a high genetic diversity among Staphylococcus spp. isolated from dairy cows with mastitis in Minas Gerais, Brazil. (AU)

• FAPESP's process: 15/10332-6 - Study of the molecular diversity of strains of Staphylococcus aureus isolated from bovine mastitis
• Grantee: Marcos Bryan Heinemann
• Support Opportunities: Regular Research Grants