Widespread distribution of tetracycline resistance genes in a confined animal feeding facility

• Published in: International journal of antimicrobial agents Vol. 29; no. 3; pp. 348 - 352
• Main Authors: Stine, O. Colin, Johnson, Judith A, Keefer-Norris, Ananda, Perry, Kellie L, Tigno, Justine, Qaiyumi, Sadaf, Stine, Maryruth S, Morris, J. Glenn
• Format: Journal Article
• Language: English
• Published: London Elsevier B.V 01.03.2007; Amsterdam Elsevier; New York, NY
• Subjects: Alleles; Animal feed; Animal Feed - microbiology; Animal Husbandry; Animals; Antibiotic resistance; Antibiotics. Antiinfectious agents. Antiparasitic agents; Bacteria - drug effects; Bacteria - genetics; Bacteria - isolation & purification; Base Sequence; Biological and medical sciences; Confined animal feeding operations; DNA, Bacterial - genetics; Enterococcus - drug effects; Enterococcus - genetics; Enterococcus - isolation & purification; Environmental Microbiology; Escherichia coli; Escherichia coli - drug effects; Escherichia coli - genetics; Escherichia coli - isolation & purification; Feces - microbiology; Food Microbiology; Genes, Bacterial; Infectious Disease; Medical sciences; Pharmacology. Drug treatments; Sequence Homology, Nucleic Acid; Sus scrofa - microbiology; Swine; Tetracycline; Tetracycline Resistance - genetics; Confined animal feeding operations; Swine; Animal feed; Antibiotic resistance; Tetracycline; Tetracycline derivatives; Operation; Feeding; Pig; Resistance; Vertebrata; Antibiotic; Mammalia; Gene; Animal; Distribution; Genetics; Artiodactyla; Protein synthesis inhibitor; Pharmacokinetics; Veterinary; Antibacterial agent; Ungulata; Feed
• ISSN: 0924-8579; 1872-7913
• DOI: 10.1016/j.ijantimicag.2006.11.015

Abstract We sought to determine the distribution of resistance and the tetracycline resistance genes among bacteria isolated from a swine confined animal feeding facility where tetracycline-containing feed had been in use for over 20 years. Samples collected from feed, hogs, hog houses, waste lagoon, soil, surface water and well water were screened for the presence of (a) resistant Escherichia coli and enterococci and (b) tetracycline-resistant strains of all species. Genomic DNA was extracted from the latter strain collection and fragments from 16S rDNA and ten tetracycline resistance genes ( tetA , tetB , tetC , tetE , tetH , tetL , tetM , tetS , tetT and rumB ) were polymerase chain reaction-amplified and a partial nucleotide sequence was obtained. In this environment, 77% of E. coli and 68% of enterococci isolated were tetracycline resistant. Tetracycline resistance was found in 26 different bacterial genera and in 60 species. Single resistance gene alleles (as defined by nucleotide sequence) were present in multiple species. There was evidence of gene recombination and multiple different tetracycline resistance genes were present in single bacterial isolates. These data provide further evidence for the widespread distribution of resistance genes in microbial populations in settings in which there is ongoing subtherapeutic antimicrobial use.