Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 5/14/2014
Publication Date: N/A
Technical Abstract: The swine gastrointestinal tract is a rich environment containing up to 1000 different species of commensal bacteria. This collection of gut bacteria, or gut microbiota, confers benefits to the host under normal conditions. Disturbance of the gut microbiota is one collateral effect of in-feed antibiotics, which have many uses in animal agriculture (disease treatment or prevention and feed efficiency improvement). We are interested in defining the swine gut microbiota and how it is affected by antibiotics to inform alternatives to growth-promoting antibiotics. To this end, we studied the impacts of ASP250 (chlortetracycline, sulfamethazine, and penicillin) on the microbiota over time and at different intestinal locations. The microbiota was analyzed for its bacterial members (via the 16S rRNA gene) and functions (via metagenomics). The results show that the gut microbiota is functionally adapted to discrete intestinal locations. For example, the large intestinal microbiota encoded a large number of genes to degrade plant cell wall components, and these genes were lacking in the ileum microbiota. Additionally, the microbiota of antibiotic-fed animals diverged from that of control animals, with notable changes being increases in Escherichia coli populations and in resistance genes to antibiotics not administered. Characterizing the gut microbiome in health and in antibiotic-mediated disturbances will inform strategies to improve swine health and food safety.