Agricultural and Biosystems Engineering Publications
Campus Units
Agricultural and Biosystems Engineering, Civil, Construction and Environmental Engineering, Bioinformatics and Computational Biology
Document Type
Article
Publication Version
Accepted Manuscript
Publication Date
6-16-2020
Journal or Book Title
Science of The Total Environment
First Page
140224
Research Focus Area(s)
Land and Water Resources Engineering
DOI
10.1016/j.scitotenv.2020.140224
Abstract
Seasonal variations of antimicrobial resistance (AMR) indicators in runoff water can help improve our understanding of AMR sources and transport within an agricultural watershed. This study aimed to monitor multiple areas throughout the Black Hawk Lake (BHL) watershed (5324 ha) in central Iowa during 2017 and 2018 that consists of both swine and cattle feeding operations as well as known areas with manure application. The measured indicators included plate counts for fecal indicator bacteria (FIB) E. coli, Enterococcus, antibiotic resistant fecal indicator bacteria (ARBs) tylosin resistant Enterococcus, tetracycline resistant Enterococcus, and antibiotic resistance genes (ARGs): ermB, ermF (macrolide), tetA, tetM, tetO, tetW (tetracycline), sul1, sul2 (sulfonamide), aadA2 (aminoglycoside), vgaA, and vgaB (pleuromutilin). Both the plate count and the ARG analyses showed seasonal trends. Plate counts were significantly greater during the growing season, while the ARGs were greater in the pre-planting and post-harvest seasons (Wilcoxon Rank-Sum Test p < 0.05). The ermB gene concentration was significantly correlated (p < 0.05) with E. coli and Enterococcus concentrations in 2017, suggesting a potential use of this ARG as an indicator of environmental AMR and human health risk. Flow rate was not a significant contributor to annual variations in bacteria and AMR indicators. Based on observed seasonal patterns, we concluded that manure application was the likely contributor to elevated ARG indicators observed in the BHL watershed, while the driver of elevated ARB indictors in the growing season can only be speculated. Understanding AMR export patterns in agricultural watersheds provides public health officials knowledge of seasonal periods of higher AMR load to recreational waters.
Access
Open
Rights
Works produced by employees of the U.S. Government as part of their official duties are not copyrighted within the U.S. The content of this document is not copyrighted.
Language
en
File Format
application/pdf
Recommended Citation
Neher, Timothy P.; Ma, Lanying; Moorman, Thomas B.; Howe, Adina; and Soupir, Michelle L., "Seasonal variations in export of antibiotic resistance genes and bacteria in runoff from an agricultural watershed in Iowa" (2020). Agricultural and Biosystems Engineering Publications. 1140.
https://lib.dr.iastate.edu/abe_eng_pubs/1140
Included in
Agriculture Commons, Bioresource and Agricultural Engineering Commons, Environmental Monitoring Commons, Water Resource Management Commons
Comments
This is a manuscript of an article published as Neher, Timothy P., Lanying Ma, Thomas B. Moorman, Adina Howe, and Michelle L. Soupir. "Seasonal variations in export of antibiotic resistance genes and bacteria in runoff from an agricultural watershed in Iowa." Science of The Total Environment (2020): 140224. DOI: 10.1016/j.scitotenv.2020.140224.