Antimicrobial resistance and molecular characterization of isolated from bovine mastitis samples in Nghe An province, Vietnam.

BACKGROUND AND AIM

Vietnam's dairy sector is in its early phase of large-scale farming development. Therefore, mastitis in cows is always a concern to farm owners. This study aimed to determine the antimicrobial susceptibility, resistance, and virulence-related genes of isolated from bovine mastitis in Nghe An province of Vietnam.

MATERIALS AND METHODS

Fifty strains were isolated from the clinical cases and subjected to this study. All isolates were tested for antimicrobial susceptibility by the disk-diffusion method, as described by the Clinical and Laboratory Standards Institute. Antimicrobial and virulence genes were confirmed by polymerase chain reaction with specific primers.

RESULTS

All isolates were resistant to lincomycin and sulfamethoxazole and sensitive to gentamicin, while other antimicrobials showed resistance from 2% to 90%. Multidrug resistance was confirmed in 46% of isolates, and none of them were identified as extended-spectrum beta-lactamase producers. From fifty strains tested for antimicrobial and virulence genes, six isolates harbored A, 6 B, 13 1, 15 2, 2 Intimin (), 1 A, and 3 2.

CONCLUSION

Antimicrobial and multidrug resistances are the main virulence factors of isolated from bovine mastitis in Vietnam. The virulence genes encoding adhesion, siderophore, Shiga-toxin-producing, and antimicrobials resistant were first reported in Vietnam with low prevalence and contributed to the pathogenesis.