Glycopeptides susceptibility among enterococci isolated from a poultry farm in São Paulo, Brazil (1996/1997)

RESUMO

Entrococci resistance to glycopeptides was evaluated in Brazilian poultry feed with feed supplemented with avoparcin as growth promoter. The susceptibility to the glycopeptides avoparcin, teicoplanin and vancomycin was determined for 217 enterococci isolated from cloacal swabes (one swab per bird) in tests and controls groups. Tests group comprised three groups (A, B and C) of Hubbard broiler-chickens 14, 21 and 35 days old, respectively. These birds were from one single farm, with a common feed source supplemented with avoparcin (10 mg/kg of feed). Controls groups (1 and 2) comprised 25 and 42 days old broilers, respectively, obtained from the faculty of Veterinary Medicine's aviary (University of São Paulo) where avoparcin was never used. No glycopeptide resistant enterococci strain was found, but and increase of Enterococcus faecium in faeces of chickens fed with avoparcin, independent of the age of the bird, was detected.