Antimicrobial resistente of Staphylococcus aureus strains isolated from dairy herds in the central region of Córdoba

PELLEGRINO, M.; FROLA, I.; BETTERA S.; FRIGERIO C.; BOGNI, C; RASPANTI, C.

Huerta Grande, Córdoba

Congreso; I Reunión Conjunta de Sociedades de Biología de la República Argentina; 2007

Asociaciones de Biología de Argentina

Staphylococcus aureus is the most important pathogen of bovine mastitis, even though in the last years others strains were frequently isolated from intra-mammary infections. Antimicrobial agents represent one of the main therapeutic tools in veterinary medicine to control and eradicate staphylococcal infections. Nevertheless, there are greater pressures from the regulatory institutions to reduce the use of antibiotic in animals of human consumption. In the present work, 48 strains identified as Staphylococcus spp. isolated from dairy herds in the central region of Córdoba, were analyzed respect to the profile of resistance to 7 antibiotics of frequent use in bovine mastitis. Antimicrobial agents tested were: penicilin (10 μg), streptomycin (10 μg), ampicylin/sulbactam (10 μg/10 μg), gentamicin (10 μg), eritromicin (15 μg), rifampicin (5 μg), and oxacilin (1 μg). The disc diffusion (Kirby-Bauer) test was use. The highest levels of antimicrobial resistance were found to penicilin (20%)and streptomycin (14%). The lowest resistance was detected in 5 (10%) and 2 (4%) isolates for ampicilin/sulbactam and rifampicin, respectively. No resistance was detected for oxacilin and gentamicin. All the resistant strains were isolated from clinical and subclinical cases of mastitis.