Aims: The effect of media type, incubation temperature and enrichment period on the species population and antibiotic susceptibility of enterococci from poultry carcass rinsates was determined.
Methods and results: Aliquots of rinsates, incubated in BBL Enterococcosel broth at 37 degrees C, 42 degrees C, or 45 degrees C for 24 and 48 h, were inoculated onto BBL Enterococcosel and M-enterococcus agar. Presumptive positive colonies were identified to species and tested for antibiotic resistance. Significant differences (P < or = 0.05) were observed for media and temperature. More Enterococcus faecalis were isolated from M-enterococcus media and at 37 degrees C while more E. faecium were isolated from Enterococcosel agar and at 45 degrees C. The number of antibiotic-resistant E. faecalis and E. faecium were also affected by media and temperature.
Conclusions: Culture conditions for enterococci affect the observed species and antibiotic resistance patterns and therefore should be carefully considered.
Significance and impact of the study: This study indicates that media and temperature can influence the recovery and selection of enterococcal species and antibiotic susceptibility.