Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: October 6, 2011
Publication Date: October 7, 2011
Citation: Looft, T.P., Stanton, T.B. 2011. Exploring the impacts of antibiotics on the microbial communities in the swine intestinal tract [abstract]. 71st Annual Meeting of the North Central Branch of the American Society for Microbiology. October 7-8, 2011. Des Moines, Iowa. 62:136. Technical Abstract: The effects of antibiotics on gastrointestinal microbial ecosystems have not been well studied. Previous research in our lab indicates that in-feed antibiotics may have unintended effects on the gut microbiota, such as an increase of Escherichia coli in feces. The goal of this study was to evaluate the effects of ASP250 on the bacterial spatial diversity in the swine intestinal tract. ASP250 (chlortetracycline, sulfamethazine, and penicillin) is an antibiotic added to swine diets for performance benefits. Feces, tissue and lumen samples (from the ileum, cecum, and colon) were collected from three-month-old pigs. Samples were collected from six control animals and six medicated animals that received ASP250 for a period of 14 days. The V1-V3 regions of the bacterial 16S rRNA genes were amplified using barcoded primers followed by pyrosequencing. Operational taxonomic unit-based analyses revealed differences related to antibiotic treatment (p less than 0.01, R=0.2616) as well as gut location (p less than 0.01, R=0.8982). E. coli numbers increased with ASP250 treatment in most intestinal sections. Differences between gut locations were the dominance of Firmicutes (specifically Clostridium and Turicibacter sp.) in the ileum, which contrasted with the higher abundance of Prevotella, Oscillibacter, and Succinivibrio in the colon. The species richness was similar between the treated and control samples at each gut location, but was much higher in the feces of the control animals. These data illustrate that antibiotics have detectable and differing impacts on the microbiota at specific gut locations. Understanding the localized effects of ASP250 will inform the design of antibiotic alternatives that mimic these effects.