Purpose: This study aimed to investigate the occurrence of clinically and agriculturally relevant AMR phenotypes in a synanthropic wild bird population.
Methods: Fecal samples (n = 75) from Canada geese were collected from public parks in Vancouver, Canada (Oct.-Dec. 2012). Samples were screened for a panel of AMR phenotypes including extended-spectrum β-lacatamase (ESBL)-producing Escherichia coli, flouroquinolone-resistant E. coli, erythromycin-resistant Enterococcus spp., and methicillin-resistant Staphylococcus aureus(MRSA). Minimum inhibitory concentrations (MICs) were determined by broth dilution assay, resistance determinants were identified by molecular characterization, and isolate relationships were assessed by BOX-PCR.
Results: ESBL-producing E. coli were recovered from 22.7% of fecal samples, while 12.0% carried ciprofloxacin-resistant E. coli, 6.7% carried erythromycin-resistant En. faecalis, 5.3% carried erythromycin-resistant En. faecium, and no MRSA was recovered. E. coli isolates from 16 samples harbored a CMY-2 β-lactamase gene, three samples possessed TEM, two contained OXA-1 and CTX-M, and four samples carried E. coli harboring multiple β-lactamase groups. Highly erythromycin-resistant Enterococcus spp. (MIC >128 µg/ml) were identified in nine samples and E. coli with ciprofloxacin MIC >16 µg/ml were observed in three samples.
Significance: The presence of enteric bacteria with resistance to clinically important antibiotics in the feces of wild geese poses a public health risk and justifies further study of the transmission of AMR between wild birds, food producing animals, and food production facilities.