Grant Information
| Knowledge Area | Subject of Investigation | Field of Science | Percent |
|---|---|---|---|
| 101 - Appraisal of Soil Resources | 110 - Soil | 2000 - Chemistry | 40% |
| 133 - Pollution Prevention and Mitigation | 210 - Water resources | 1100 - Bacteriology | 40% |
| 112 - Watershed Protection and Management | 210 - Water resources | 2050 - Hydrology | 20% |
Antimicrobials are used in production agriculture to treat disease and promote animal growth, but the presence of antibiotics in the environment raises concern about widespread antibiotic resistance. The goal of this study, which addresses a research priority of the Renewable Energy, Natural Resources, and Environment Program, is to improve the understanding of the fate and transport of veterinary antibiotics, antibiotic-resistant bacteria and genes in soil, surface runoff, and tile-drained water to surface water in agricultural watersheds. The specific objectives are to determine the losses of antibiotics from manured fields in runoff water, tile drainage and water leaching to groundwater; determine the concurrent losses of antibiotic-resistant bacteria and antibiotic-resistance genes from manured fields in runoff water, tile drainage and water leaching to groundwater; and evaluate and improve the capabilities of the Root Zone Water Quality Model to predict losses of antibiotics. The plan to accomplish the goal includes plot- and catchment-scale experiments with different manure sources and management practices to measure the fate and transport of antibiotics, antibiotic-resistant bacteria, and antibiotic-resistant genes and supporting experiments to help parameterize the model. Outcomes include an improved understanding of how antibiotics and antibiotic-resistance bacteria and genes move in Midwestern landscapes, emphasizing the role of macropore flow and other infiltration mechanisms, and a parameterized plot/field-scale model to predict antibiotic transport to water under varying antibiotic application rates and rainfall patterns. The ability to predict fate and transport ofantibiotic-resistant bacteria and antibiotic-resistance genes will aid in addressing the long term goal of protecting environmental, human, and animal health.
The long-term goal of this research is to improve the understanding of the fate and transport of veterinary antibiotics, antibiotic-resistant bacteria and resistance genes (CEC, contaminants of emerging concern) in soil, surface runoff, and tile-drained water to surface water in agricultural watersheds.
The issues of agricultural antibiotic use, antibiotic residues in the environment and agriculture-induced changes in abundance of antibiotic resistant genes are not separate issues, but require integrated approaches such as those described in this project. This research directly addresses the movement of antibiotics and antibiotic-resistance genes in surface runoff and tile drainage from manured fields. Field plot/catchment scale monitoring of antibiotics, antibiotic-resistance genes (ARG) and antibiotics-resistant Enterococcus will be conducted at three locations: Field 5 near Ames, IA (poultry manure); Iowa State University Northeast Research and Demonstration Farm near Nashua, IA (swine manure); and the Pioneer Farm, near Platteville, WI (beef manure). We will quantify losses of focus antibiotics (tetracycline, sulfamethazine and tylosin), related antibiotic resistance genes, and total and resistant Enterococcus in manure, surface soils and tile drainage and/or surface runoff under natural conditions over three growing seasons. Each site will have measurements that allow the direct comparison of the manure-treated area to a control (no manure). Additionally we will conduct rainfall simulation experiments on sub-areas of the selected plots in a manner designed to force surface runoff and obtain macropore flow. These controlled experiments will allow detailed measurement ofARG and antibiotictransport and the data from these studies will be used for calibration of the Root Zone Water Quality Model (RZWQM). We also propose supporting laboratory experiments to identify unknown parameters (for example, sorption and degradation rates)needed for model development and testing. Once calibration of the RZWQM is obtained we will model the field plot/catchment scale data. The experimental work will be accomplished in the first three years of the project with the fourth year devoted to modeling, data analysis, and reporting the results in scientific journals.
Target Audience
The target audiece includes scientists, farmers that produce animals or utilize animal manure, and non-governmental organizations interested in agriculture and enviromnmental issues.
Changes / Problems
The funded proposal included a modeling component that was not achieved during the project period. The intent was to conduct this using the plot-scale antibuiotic transport data, but the grant expireed before this could be accomplished. The original proposal called for analysis of tetracycline by ELISA methods. Because ARS purchased an advanced LC-mass spectrometer during the first year of the project, that technology was adopted because of it's lower limits of detection and verification using analysis of daughter product ratios.
Training & Professional Development
The grant provided partial funding for Maurice T Washington and Elizabeth Rieke for graduate studies inAgricultural Engineering at Iowa State University.Dr. Washington received a PhD in Agricultural Engineering in summer of 2017 and performed much of the research antibiotic fate and transport.The project also provided support to a post-doctoral Research Associate (Dr. Bailey Sullivan, ISU) which allowed her to gain experiece in antibiotic chemistry and qPCR technology.
Dissemination Streams
Research results were dessiminate to audiences that included veterinarians, scientists, federal or state agency representatives, agricultural consultants,and animal producers at the conferences listed below. Soupir, M.L. 2017. Environmental aspects of antibiotic use in swine production. Presented at the Allen D. Leman Swine Conference in Minneapolis, MN. 9/19/17. Soupir, M.L. 2017. Fate and transport of antimicrobial resistant genes in agricultural landscapes. University of Nebraska Lincoln Manure and Soil Health (MaSH) Roundtable Presentation. 2/16/17. Iowa State University. 75 participants
Next Reporting Steps
Nothing Reported