ANTIMICROBIAL DRUG RESISTANCE OF Staphylococcus sp ISOLATED FROM HEALTHY LACTATING COWS OF AN ORGANIC FARM.

RODOLPHO, D.M. MARIN, J.L. C. ARAUJO, M.

A total of 95 Staphylococcus sp strains, isolated from 129 apparently healthy lactating cows from an organic farm situated in São Paulo State, Brazil, were characterized for resistance to 7 antimicrobial drugs. Resistance to penicillin was most frequently (96.8%) found, followed by resistance to streptomycin (67.3%), norfloxacin (31.5%) and vancomycin (5.2%). -Lactamase production was found in 21.0% of the isolates. Multidrug resistant isolates were common and two patterns of phenotypes were found in 78.9% of the isolates. These results showed that cows not exposed to antimicrobial drugs for five years still presented a high level of antimicrobial resistance among the colonizing bacteria of these animals.KEY-WORDS: Staphylococcus sp. Antimicrobial drug resistance. Homeopathic treatment. Multidrug resistance.