Exploring the Bacterial Community in Aged Fecal Sources from Dairy Cows: Impacts on Fecal Source Tracking

• Published in: Microorganisms (Basel) Vol. 11; no. 5; p. 1161
• Main Authors: Devane, Megan L, Taylor, William, Dupont, Pierre-Yves, Armstrong, Bridget, Weaver, Louise, Gilpin, Brent J
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 28-04-2023; MDPI
• Subjects: 16S rRNA; Aging; Agricultural ecosystems; Animal waste; Aquatic environment; Bacteria; Cattle; Causes of; cowpat; Creeks & streams; Dairy cattle; Decomposition; Environmental aspects; FEAST; fecal bacterial decay; Fecal coliforms; Fecal microflora; fecal source tracking; Feces; Floods; Health aspects; Machine learning; Metagenomics; Methods; Microbial activity; Microbial source tracking; Microbiomes; Microbiota; Microbiota (Symbiotic organisms); Microorganisms; New Zealand; Pathogens; Pollution; Pollution monitoring; Rainfall; rRNA 16S; Runoff; Simulated rainfall; Stream pollution; Streams; Tracking; Water monitoring; Water pollution; Water quality; Water quality management; Waterways; New Zealand; United States > US; Germany; 16S rRNA; FEAST; cowpat; fecal bacterial decay; fecal source tracking; metagenomics
• ISSN: 2076-2607; 2076-2607
• DOI: 10.3390/microorganisms11051161

(1) Background: This paper discusses the impact of agricultural activities on stream health, particularly in relation to dairy cow fecal pollution. The study explores the fecal microbiome of cattle and the potential ecological implications of aging fecal pollution on waterways. (2) Methods: The study examines changes in the bacterial community available for mobilization from in-situ decomposing cowpats and the effects of simulated rainfall. The microbiome of individual cowpats was monitored over 5.5 months. We used 16S rRNA metagenomics and machine learning software, FEAST (Fast Expectation-mAximization for microbial Source Tracking), for bacterial and fecal source assignments. (3) Results: The phyla Bacillota and Bacteroidota are dominant in the fecal microbiota of fresh cow feces but shift to Pseudomonodota, Actinomycetota, and environmental Bacteroidota in aged cowpats. Potential impacts of these bacterial community shifts on inputs to local agricultural streams are discussed in relation to water quality monitoring and aging sources of fecal contamination. We identified taxon orders that are potential indicators of fresh cattle sources (Oscillospirales and Bacteroidales) and aged sources (Peptostreptococcales-Tissierellales) in water bodies. (4) The paper highlights that bacterial metagenomic profiling can inform our understanding of the ecology of microbial communities in aquatic environments and the potential impacts of agricultural activities on ecosystem health.