Study on antimicrobial resistance of Staphylococcus aureus isolated from dogs at veterinary clinics in Ho Chi Minh City

Abstract

This study was conducted to evaluate the antimicrobial resistance of the isolated Staphylococcus aureus from dogs by disk diffusion method with 14 tested antibiotics according to CLSI guidelines. The studied results showed that the infection rate of samples with S. aureus was 40/48 (83.33%) isolated and identified. The bacterial strains resisted to several antimicrobial groups, of which they were strongly resistant to β-lactams group, such as: penicillin (95%), ampicillin (87.5%), amoxicillin/clavulanic acid (55%), ceftriaxone (32.5%). Even though oxacillin was not used in veterinary medicine, the tested result revealed that the resistant ratio of the isolated S. aureus strains to this antibiotic was 25% and the intermediate resistant ratio was 5%. The resistant rate of S. aureus strains was also high to gentamicin (40%), tetracycline (32.5%), and ciprofloxacin (35%). The rate of bacteria were developing high resistant characteristics to the commonly used antibiotics revealed by the high intermediate susceptible ratio (17.5 – 40%). Most of the isolates were multi-resistant phenotype (82.5%), resistance to 7 or more antibiotics