ARS | Publication request: Antibiotics and gene transfer in swine gut bacteria

Submitted to: Feedinfo News Service
Publication Type: Popular Publication
Publication Acceptance Date: December 27, 2012
Publication Date: December 27, 2012
Citation: Allen, H.K. 2012. Antibiotics and gene transfer in swine gut bacteria. Feedinfo News Service. Available: http://www.feedinfo.com.

Technical Abstract: The mammalian gastrointestinal (GI) tract hosts a diverse collection bacteria, most of which are beneficial for host health. This bacterial community also supports a community of viruses that infect bacteria (called bacteriophages or phages). Phages transfer genes between bacteria, and phage-mediated gene transfer is important to bacterial evolution. Previous research has shown that the antibiotic carbadox stimulates phage-mediated gene transfer in certain pathogens. In the study being discussed in this article, we investigated phage diversity and the effects of in-feed antibiotics on this diversity in the total swine gut microbial community. This was possible via modern technologies such as next-generation DNA sequencing, which are an essential tool to survey complex communities such as the gastrointestinal microbiota. The results of our study showed that phages increased in abundance in antibiotic-treated pigs compared to non-medicated pigs, suggesting that antibiotics induced phages with antibiotic treatment. Additionally, populations of the bacterium E. coli increased with antibiotic treatment. Taken together, the results are an important reminder of the evolutionary stimulus that is antibiotic treatment. These and other studies from our lab present data on the ecology of the swine GI microbiota as it relates to food safety issues. Our objective is to investigate the effects of in-feed antibiotics on the GI microbiota, and in future experiments on the host, with the goal of discovering targets for antibiotic alternatives. Alternatives to in-feed antibiotics are an active area of research in our lab group, including both feed additives and vaccines.