An official website of the United States government.

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

Effect of Tetracycline Use in Animals on Appearance and Dissemination of Resistance to Third Generation Tetracyclines


The main objective of this proposal is to evaluate the pool of novel antibiotic resistance genes in swineherds with different antibiotic use regimens, conventional and organic. <P>
The hypothesis will be tested that in conventional herds the pool of tetracycline resistance genes is larger, thus increasing the probability of mutations/transpositions leading to resistance to third generation tetracyclines. The pool of these mutant alleles will be estimated through the metagenomic analysis. Genetic transfer potential of these genes will be evaluated by sequence analysis of surrounding regions as well as in conjugation experiments. <P>The possibility of dissemination of these genes will be through quantitative real-time PCR detection in feed components, water, and environmental samples. This proposal is in lines with the general strategy of DEFRA and VDM to protect public and animal health by ensuring the safety of veterinary medicinal products. Tetracyclines account for about a half of all antibiotics used in food animals thus sustaining a high tetracycline resistance gene pool, the starting material for mutations and insertions leading to resistance to the novel tetracyclines, glycylcyclines, which are currently in phase II clinical trials.<P> Results obtained are intended for use in early warning monitoring efforts to prevent the transmission of these resistance genes to human and animal pathogens. Data generated in this study will provide background information for antibiotic usage policy in food animals.

Rowett Research Institute
Start date
End date
Project number