Submitted to: Microbial Ecology International Symposium
Publication Type: Abstract Only
Publication Acceptance Date: 5/31/2008
Publication Date: 8/17/2008
Citation: Shanks, O.C., White, K.M., Hayes, S., Kelty, C.A., Sivaganesan, M., Jenkins, M., Sogin, M.L. 2008. Influence of diet on the performance of bovine fecal pollution detection methods and microbial population structure [abstract]. 12th International Symposium on Microbial Ecology, August 17-22, 2008, Cairns, Queensland, Australia.
Technical Abstract: Background and Aims. Waterborne diseases originating from bovine fecal material are a significant public health issue. Ensuring water quality requires the use of methods that can consistently identify pollution across a broad range of management practices. One practice that is often overlooked is animal diet. Different diet regimes are known to have a significant impact on rumen microbial ecology. Shifts in rumen microbial population structure influenced by diet may also impact fecal microbial communities and the performance of bovine fecal pollution detection methods. Methods. Seven PCR assays (4 end-point; 3 quantitative) that target Bacteroidetes 16S rRNA or Bacteroidetes-like chromosomal genes were tested with randomly selected individual bovine fecal samples from pasture (n=60), corn grain (n=60), and distiller grain (n=30) fed animals representing five test populations. Fecal samples were obtained by digital retrieval from the rectum of each animal. A massive parallel sequence strategy was used to characterize the microbial population structure from individual fecal samples (n=4) representing different diet types. Results. The number of positive detections from each population using end-point PCR assays ranged from 0% to 100%. Abundance of quantitative PCR target DNA varied between pasture and corn fed diets (p<0.05). More than 100,000 sequence tags provided a detailed microbial population profile that allowed us to compare the effects of different diet types. Conclusions. Different diet regimes can have a drastic influence on the performance of bovine fecal detection methods. Study results demonstrate the importance of diet and characterizing microbial population structure when developing fecal source tracking methods.