title: Tetracycline resistance in semi-arid agricultural soils under long-term swine effluent application.
abstract: Annually, millions pounds of antibiotics are released unmetabolized into environment along with animal wastes. Accumulation of antibiotics in soils could potentially induce the persistence of antibiotic resistant bacteria. Antibiotics such as tetracyclines and tetracycline-resistant bacteria have been previously detected in fields fertilized with animal manure. However, little is known about the accumulation of tetracyclines and the development of tetracycline resistance in semi-arid soils. Here we demonstrate that continuous land application with swine effluent, containing trace amounts of chlortetracycline, does not necessarily induce tetracycline resistance in soil bacteria. Based on the testing of more than 3,000 bacteria isolated from the amended soils, we found no significant increase in the occurrence and level of chlortetracycline resistant bacteria in soils after 15 years of continuous swine effluent fertilization. To account for a possible transfer of tetracycline-resistant bacteria originated from the swine effluent to soils, we analyzed two commonly found tetracycline resistant genes, tet(O) and tet(M), in the swine effluent and fertilized soils. Both genes were present in the swine effluent, however, they were not detectable in soils applied with swine effluent. Our data demonstrate that agronomic application of manure from antibiotic treated swine effluent does not necessarily result in the development of antibiotic bacterial resistance in soils. Apparently, concentrations of chlortetracycline present in manure are not significant enough to induce the development of antibiotic bacterial resistance.
authors.affiliation: a Department of Plant , Soil, and Entomological Sciences, University of Idaho , Moscow , Idaho , USA.|b Department of Plant and Soil Sciences , Oklahoma State University , Stillwater , Oklahoma , USA.
authors.forename: Inna E
authors.initials: IE
authors.lastname: Popova
authors.affiliation: b Department of Plant and Soil Sciences , Oklahoma State University , Stillwater , Oklahoma , USA.
authors.forename: Rosemarie D R
authors.initials: RDR
authors.lastname: Josue
authors.affiliation: b Department of Plant and Soil Sciences , Oklahoma State University , Stillwater , Oklahoma , USA.
authors.forename: Shiping
authors.initials: S
authors.lastname: Deng
authors.affiliation: c School of Environment & Natural Resources , Ohio State University , Columbus , Ohio , USA.
authors.forename: Jeffory A
authors.initials: JA
authors.lastname: Hattey
mesh_terms: D000383:Agriculture; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects*; D002751:Chlortetracycline / Q000032:analysis / Q000494:pharmacology; D005308:Fertilizers; D008372:Manure / Q000382:microbiology*; D008826:Microbial Sensitivity Tests; D009825:Oklahoma; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000032:analysis; D013552:Swine; D013752:Tetracycline / Q000494:pharmacology; D013753:Tetracycline Resistance / Q000187:drug effects*; D013754:Tetracyclines / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D005308:Fertilizers; D008372:Manure; D012989:Soil Pollutants; D013754:Tetracyclines; D013752:Tetracycline; D002751:Chlortetracycline
keywords: Soil; animal waste; antibiotic resistance; antibiotics; chlortetracycline; manure; semi-arid; swine effluent