ARS | Publication request: Antimicrobial resistance in Enterococcus spp. isolated from environmental samples in the area of intensive poultry production

Submitted to: International Journal of Environmental Research and Public Health
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 4, 2013
Publication Date: N/A

Interpretive Summary: Fraser Valley in the province of British Columbia is considered the poultry capital of Canada. The poultry waste generated from the industry is used as fertilizer and spread onto the fields thus creating scattered sources of surface and groundwater pollution. In this study, we investigated antimicrobial resistance of Enterococcus spp. from different environmental compartments including litter from two farms, 12 surface and 28 groundwater sites in an area of intensive poultry production and litter application. Overall, 14% of litter isolates, 42% of surface water isolates and 0% of groundwater isolates were resistant to one antibiotic. Statistical analyses was applied to the resistance data set for source tracking and indicated that poultry was a possible source of the surface water contamination observed. Data presented in this study is of interest to researchers who can use this information to assess the relative contribution of poultry waste to contamination of water sites with antimicrobial resistant bacteria and in designing strategies to reduce microbial contamination of the environment.

Technical Abstract: In this study, we investigated antimicrobial resistance of Enterococcus spp. from different environmental compartments including litter from two farms, 12 surface and 28 groundwater sites in an area of intensive poultry production and litter application. The enumerated isolates (n=250) were tested for resistance to 16 clinical antibiotics. Enterococcal spp. were detected in all surface water samples and three groundwater sites. Resistance in litter to lincomycin, tetracycline, penicillin and ciprofloxacin was high (80.3%, 65.3%, 61.1% and 49.6%, respectively). Resistance in the surface water to these antibiotics was 87.1%, 24.1%, 7.6% and 12.9%, respectively. Overall, 14% of litter isolates, 42% of surface water isolates and 0% of groundwater isolates were resistant to one antibiotic (AR). Fifty-four different resistance patterns were recognised in litter and environmental samples and several E. faecium and E. faecalis isolates from litter and environment samples shared the same pattern. Multiple antibiotic resistant (MAR) indexes were calculated in order to assess the health risks due to presence of resistant enterococci. The statistical analyses principal component analysis (PCA) was applied on the resistance data set for source tracking and indicated that poultry was a possible source of the surface water contamination observed.