This Article Full Text Full Text (PDF) Other Versions of this Article: AEM.00665-07v1 73/15/4813    most recent Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Koike, S. Articles by Mackie, R. I. Search for Related Content PubMed PubMed Citation Articles by Koike, S. Articles by Mackie, R. I. Agricola Articles by Koike, S. Articles by Mackie, R. I.

 Previous Article  |  Next Article 

Applied and Environmental Microbiology, August 2007, p. 4813-4823, Vol. 73, No. 15
0099-2240/07/$08.00+0     doi:10.1128/AEM.00665-07
Copyright © 2007, American Society for Microbiology. All Rights Reserved.

Monitoring and Source Tracking of Tetracycline Resistance Genes in Lagoons and Groundwater Adjacent to Swine Production Facilities over a 3-Year Period

S. Koike,^1, I. G. Krapac,² H. D. Oliver,¹ A. C. Yannarell,¹ J. C. Chee-Sanford,³ R. I. Aminov,⁴ and R. I. Mackie^1*

Department of Animal Sciences, University of Illinois at Urbana-Champaign,¹ USDA Agricultural Research Service, Urbana, Illinois 61801,³ Illinois State Geological Survey, Champaign, Illinois 61820,² Rowett Research Institute, Aberdeen AB21 9SB, United Kingdom⁴

Received 23 March 2007/ Accepted 25 May 2007

To monitor the dissemination of resistance genes into the environment, we determined the occurrence of tetracycline resistance (Tc^r) genes in groundwater underlying two swine confinement operations. Monitoring well networks (16 wells at site A and 6 wells at site C) were established around the lagoons at each facility. Groundwater (n = 124) and lagoon (n = 12) samples were collected from the two sites at six sampling times from 2000 through 2003. Total DNA was extracted, and PCR was used to detect seven Tc^r genes [tet(M), tet(O), tet(Q), tet(W), tet(C), tet(H), and tet(Z)]. The concentration of Tc^r genes was quantified by real-time quantitative PCR. To confirm the Tc^r gene source in groundwater, comparative analysis of tet(W) gene sequences was performed on groundwater and lagoon samples. All seven Tc^r genes were continually detected in groundwater during the 3-year monitoring period at both sites. At site A, elevated detection frequency and concentration of Tc^r genes were observed in the wells located down-gradient of the lagoon. Comparative analysis of tet(W) sequences revealed that the impacted groundwater contained gene sequences almost identical (99.8% identity) to those in the lagoon, but these genes were not found in background libraries. Novel sequence clusters and unique indigenous resistance gene pools were also found in the groundwater. Thus, antibiotic resistance genes in groundwater are affected by swine manure, but they are also part of the indigenous gene pool.

Published ahead of print on 1 June 2007.

Present address: Creative Research Initiative Sousei, Hokkaido University, Sapporo 001-0021, Japan.