Phenotypic distinction in Enterococcus faecium and Enterococcus faecalis strains between susceptibility and resistance to growth-enhancing antibiotics.
Susceptibility of Enterococcus faecium and Enterococcus faecalis strains from animals and foods to growth-promoting antibiotics used in animal feed was tested by the agar dilution technique. Acquired resistance to bacitracin, narasin, tylosin, and virginiamycin was seen for both species, and for E. faecium, resistance to avilamycin and avoparcin was also seen. Drawing the distinction between susceptibility and resistance based on frequency distributions of MICs was easy with avoparcin, avilamycin, and tylosin but difficult with virginiamycin and to some extent also with bacitracin and narasin.
Butaye
P
P
Laboratory of Bacteriology and Mycology, Department of Pathology, Bacteriology, and Avian Diseases, Faculty of Veterinary Medicine, University of Ghent, B-9820 Merelbeke, Belgium. pbutaye@allserv.rug.ac.be
Devriese
L A
LA
Haesebrouck
F
F
D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D013293:Enterococcus faecalis / Q000187:drug effects* / Q000254:growth & development; D016984:Enterococcus faecium / Q000187:drug effects* / Q000254:growth & development; D005516:Food Microbiology; D006020:Glycopeptides; D008826:Microbial Sensitivity Tests; D009844:Oligosaccharides / Q000494:pharmacology; D010641:Phenotype; D011714:Pyrans / Q000494:pharmacology
D000900:Anti-Bacterial Agents; D006020:Glycopeptides; D009844:Oligosaccharides; D011714:Pyrans; C006653:avilamycin; C013612:narasin; C016249:avoparcin