Title: Bacteria, phages, and pigs: The effect of in-feed antibiotics on bacterial membership, metabolic potential, and phages in different gut locations
Authors: Looft TP, Allen HK, Cantarel B, Levine UY, Bayles DO, Alt DP, Henrissat B, Stanton TB
Journal: J Int Soc Microbial Ecol
Accepted date: 2014 Jan 10
Interpretive summary: Central to the debate surrounding the use of antibiotics that stop diseases or enhance growth of food-producing animals is the question, what are the broader and unknown effects of these antibiotics on gut bacteria? In our work we are defining the effects of one particular mixture of antibiotics that is administered to swine in the feed. Through metagenomic analyses (sequencing all of the microbial genes in intestinal samples), we found location-specific differences in gut bacteria that are important for determining antibiotic effects. We found that there are fewer types of bacteria in the small intestine than in the large intestine. Interestingly, there are more different bacteria associated with the mucosa (inner wall) of the small intestine than in the contents. This suggests that the mucosa is an important even if understudied habitat for gut bacteria. The data also show that the microbial activities are differentiated between small versus large intestine, suggesting that each microbial community is adapted to the local gut environment. Finally, we discovered that the antibiotic mixture changed the gut microbial community, both in terms of membership and function. Defining specific intestinal microbial communities and the effect of antibiotics on them will guide us in selecting effective alternatives to in-feed antibiotics and ultimately will help to improve food safety.
Publication date: 2014 Feb 13
Related projects: Animal Intestinal Microbiomes, Foodborne Pathogens, and Antimicrobials