Bacterial source tracking using Bacteroidetes 16S rDNA isolated from environmental samples. freshwater metagenome

This study assessed hog lagoon waste contamination in watersheds using Bacteroidetes 16S rRNA gene pyrosequencing. Previous research using Bacteroidetes 16S rDNA has relied on direct fecal markers from pig hosts, as opposed to hog lagoon waste, and a relatively small number of sequences. These limitations can lead to an underestimation or a failure to detect hog lagoon waste in environmental samples. In our study, we analyzed 31,459 Bacteroides 16S rDNA amplicons from water samples from 4 river sites during 5 different months in the Cape Fear Watershed, and waste samples from 6 hog lagoons within the Cape Fear watershed. Using a strict 97% sequence similarity cutoff, we identified specific hog lagoon markers, which are different from pig fecal markers.