Quinolone resistance in potentially pathogenic and non-pathogenic Escherichia coli strains isolated from healthy ruminants

Quinolone resistance was studied in potentially pathogenic and non-pathogen ic Escherichia coli strains from healthy ruminants. In cattle, 5.9% of the strains were resistant to nalidixic acid and 4.9% were resistant to enroflo xacin and ciprofloxacin, whereas in sheep and goats only 0.5% and 1.4%, res pectively, of the strains were resistant to nalidixic acid and none to fluo roquinolones. Most of the strains resistant to quinolones were non-pathogen ic strains isolated from cattle. However, the results of this study do not show that the potentially pathogenic E. coli strains isolated from healthy ruminants are more susceptible to quinolones than the non-pathogenic E. col i strains.