Publication
Title
Selection and transfer of an IncI1-tet(A) plasmid of Escherichia coli in an ex vivo model of the porcine cecum at doxycycline concentrations caused by cross-contaminated feed
Author
Abstract
Aims The aim of this study was to investigate the effect of subtherapeutic intestinal doxycycline (DOX) concentrations (4 and 1 mg l-1), caused by cross-contamination of feed, on the enrichment of a DOX resistant commensal E. coli and its resistance plasmid in an ex vivo model of the porcine cecum. Methods and Results A DOX resistant, tet(A) carrying, porcine commensal E. coli strain (EC 682) was cultivated for 6 days in the porcine cecum model under different conditions (0, 1 and 4 mg l-1 DOX). EC 682, other coliforms and anaerobic bacteria were enumerated daily. A selection of isolated DOX resistant coliforms (n=454) was characterized by rep-PCR clustering, PCR assays [Inc1 and tet(A)] and micro broth dilution susceptibility tests (Sensititre). Both 1 and 4 mg l-1 DOX enriched medium had a significantly higher selective effect on EC 682 and other resistant coliforms than medium without DOX. Transconjugants of EC 682 were isolated more frequently in the presence of 1 and 4 mg l-1 DOX compared to medium without DOX. Conclusions Subtherapeutic intestinal DOX concentrations have the potential to select for DOX resistant E.coli, and promote the selection of transconjugants in a porcine cecum model. Significance and Impact of Study Cross-contamination of feed with antimicrobials such as DOX likely promotes the spread of antimicrobial resistance. Therefore it is important to develop or fine-tune guidelines for the safe use of antimicrobials in animal feed and its storage.
Language
English
Source (journal)
The journal of applied microbiology. - London
Publication
London : 2017
ISSN
1364-5072
DOI
10.1111/JAM.13561
Volume/pages
123 :5 (2017) , p. 1312-1320
ISI
000413317600022
Pubmed ID
28799283
Full text (Publisher's DOI)
Full text (open access)
UAntwerpen
Faculty/Department
Research group
Publication type
Subject
Affiliation
Publications with a UAntwerp address
External links
Web of Science
Record
Identifier
Creation 07.10.2017
Last edited 09.10.2023
To cite this reference