title: Dissemination of ESBL-producing Escherichia coli of chicken origin to the nearby river water.
abstract: The dissemination of drug-resistant bacteria from animal farms to aquatic environments can pose a potential threat to public health. In this study, antimicrobial resistance, resistance genes, and genetic similarity of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli of different origins (chicken feces and upstream and downstream river waters) were analyzed to track the spread of drug-resistant bacteria of animals. The results showed that a total of 29 ESBL-producing E. coli were obtained from 258 samples, and isolation rates of the ESBL-producing E. coli from chicken feces and upstream and downstream waters were 10.7% (16/150), 3.7% (1/27), and 14.8% (12/81), respectively. The ESBL-producing E. coli from upstream water was resistant to 7 antibiotics, but isolates from feces and downstream water had a higher resistance rate. In 29 ESBL-producing E. coli, the most common gene was CTX-M and the SHV gene was not detected. Five ESBL-producing isolates from downstream water showed >90% similarity with the fecal isolates, while the only one isolate from upstream water had <70% similarity with fecal isolates. The results suggest that animal farms' effluent, especially the untreated wastewater, could contribute to the spread of resistance genes.
authors.affiliation: College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Jinan, China.
authors.forename: Lili
authors.initials: L
authors.lastname: Gao
authors.forename: Jiaqing
authors.initials: J
authors.lastname: Hu
authors.forename: Xiaodan
authors.initials: X
authors.lastname: Zhang
authors.forename: Ruihua
authors.initials: R
authors.lastname: Ma
authors.forename: Jing
authors.initials: J
authors.lastname: Gao
authors.forename: Song
authors.initials: S
authors.lastname: Li
authors.forename: Miaoqing
authors.initials: M
authors.lastname: Zhao
authors.forename: Zengmin
authors.initials: Z
authors.lastname: Miao
authors.forename: Tongjie
authors.initials: T
authors.lastname: Chai
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000378:metabolism*; D002645:Chickens; D016000:Cluster Analysis; D004269:DNA, Bacterial / Q000235:genetics; D024881:Drug Resistance, Bacterial; D004926:Escherichia coli / Q000145:classification / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification*; D005243:Feces / Q000382:microbiology*; D005798:Genes, Bacterial; D005838:Genotype; D058889:Molecular Typing; D045483:Rivers / Q000382:microbiology*; D001618:beta-Lactamases / Q000378:metabolism*
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D004269:DNA, Bacterial; D001618:beta-Lactamases; C063912:carbapenemase