These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Persistence of an antibiotic resistance plasmid in intestinal Escherichia coli of chickens in the absence of selective pressure.
    Author: Chaslus-Dancla E, Gerbaud G, Lagorce M, Lafont JP, Courvalin P.
    Journal: Antimicrob Agents Chemother; 1987 May; 31(5):784-8. PubMed ID: 3300540.
    Abstract:
    We studied eight strains of Escherichia coli resistant to high levels of trimethoprim that were isolated over a 6-week period in a commercial breeding flock of broilers. The strains originated from fecal samples and from a carcass immediately after slaughter. Seven of eight strains belonged to the same infrequent biotype. They were also resistant to ampicillin and streptomycin, and some were resistant to tetracycline and potassium tellurite. All the strains transferred trimethoprim and ampicillin resistance to E. coli. Analysis of the donors and of the transconjugants by agarose gel electrophoresis after digestion by restriction endonucleases and by nucleic acid hybridization indicated that resistance to trimethoprim (dfrI) and to ampicillin (bla TEM-1) was mediated by a 65-kilobase plasmid, pIP1531. Persistence of resistance to trimethoprim and ampicillin in this flock was therefore due to two cumulative factors, both occurring in the absence of selective pressure, namely the dissemination of a particular plasmid between strains and the ability of an atypical E. coli strain to stably colonize many animals.
    [Abstract] [Full Text] [Related] [New Search]