Investigating the dispersal of antibiotic resistance associated genes from manure application to soil and drainage waters in simulated agricultural farmland systems

PLoS One. 2019 Sep 17;14(9):e0222470. doi: 10.1371/journal.pone.0222470. eCollection 2019.

Abstract

Manure from animals that have been treated with antibiotics is often used to fertilize agricultural soils and its application has previously been shown to enrich for genes associated with antibiotic resistance in agroecosystems. To investigate the magnitude of this effect, we designed a column experiment simulating manure-treated agricultural soil that utilizes artificial subsurface drainage to determine the duration and extent which this type of manure fertilization impacts the set of genes associated with antibiotic resistance in drainage water. We classified ARGs in manure-treated drainage effluent water by its source of origin. Overall, we found that 61% and 7% of the total abundance of ARGs found in drainage water samples could be attributed to manure enrichment and manure addition, respectively. Among these ARGs, we identified 75 genes unique to manure that persisted in both soil and drainage water throughout a drainage season typical of the Upper Midwestern United States. While most of these genes gradually decreased in abundance over time, the IS6100-associated tet(33) gene accrued. These results demonstrate the influence of manure applications on the composition of the resistome observed in agricultural drainage water and highlight the importance of anthropogenic ARGs in the environment.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Agriculture / methods
  • Animals
  • Anti-Bacterial Agents / pharmacology
  • Drainage / methods
  • Drug Resistance, Microbial / genetics*
  • Farms
  • Genes, Bacterial / genetics
  • Manure / microbiology*
  • Midwestern United States
  • Soil
  • Soil Microbiology

Substances

  • Anti-Bacterial Agents
  • Manure
  • Soil

Grants and funding

This project was supported by AFRI food safety grant no. 2016-68003-24604 from the USDA National Institute of Food and Agriculture (https://nifa.usda.gov/program/agriculture-and-food-research-initiative-afri) to AH, MLS, TBM, and HKA. The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.