Date of Graduation

Fall 2009


Master of Science in Biology



Committee Chair

John Steiert


Microbial source tracking (MST) is a general term given to any process which aims to determine the source of microbial contamination found in an environmental (usually water) sample. These methods include both phenotypic and genotypic strategies. In this study, quantitative PCR was used to evaluate water samples for species specific (cow and human) Bacteroides in the Finley River. The Finley River is susceptible to impacts from both bovine and humans as it flows through farmland and urban areas. Water samples were collected from sites identified in a previous study that had high E. coli levels. Two samples were collected at each site (One sample for enumeration of E. coli and the other to assay for Bacteroides). Sampling was done approximately three times per month for one year. For each sampling event, pH, DO, turbidity, water temperature, flow rate, and rainfall were recorded. The results showed lower than expected cow markers throughout the sampling period; while human markers were much more prevalent than cow markers during the drier (and warmer) months. A correlation was found between human specific Bacteroides markers and E. coli at one site, but not at either of the other two sites. This method affords more informative surveillance data to area health departments so more appropriate remediation strategies can be developed.


Bacteroides, microbial source tracking, 16SrRNA, E. coli, fecal indicator, qPCR

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