Use of antibiotic resistance analysis as a bacterial source tracking technique to facilitate water-resource management in South Dakota (Escherichia coli)

Water pollution by fecal material is an increasingly important issue throughout the United States. The past 20 years have provided a dramatic growth in bacterial source tracking methods, one goal of which is to develop and use reliable methods to identify the source of E. coli in surface waters. For the study described, antibiotic resistance analysis (ARA) of E. coli strains from human and animal sources was used to see if ARA patterns of E. coli strains from different hosts and ecoregions in South Dakota differed significantly. Use of ARA analysis requires that a database of bacterial isolates be constructed as a reference before the likely origin of E. coli found in the surface waters can be evaluated. In this study, a database of approximately 2800 E. coli isolates from seven different host sources from four different ecoregions in South Dakota was constructed. The four ecoregions studied were the Middle Rockies, Northwestern Glaciated Plains, Northwestern Great Plains, and Northern Glaciated Plains. (Abstract shortened by UMI.)...