ARS | Publication request: Investigating the Overlooked Genomes That Impact Animal Health: The Gut Microbiome

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: March 15, 2010
Publication Date: N/A

Technical Abstract: The mucosal surfaces of humans and animals are colonized by a diverse microbiota that contributes significantly to host health. The gut microbiome influences animal health through assuring nutritional uptake and metabolism, developing and mediating innate immunity, and modulating virulence and abundance of pathogens. The NADC is investigating links between the gut microbiome and animal health from two perspectives: 1) Bacteria-bacteria interactions on prevalence and virulence of foodborne pathogens within the turkey cecum; and 2) Intestinal microbiome dynamics in swine fed a diet containing antibiotics (ASP 250). 16S rRNA gene analysis of turkey cecal microbes revealed increased microbial population diversity and composition between 12 to 13 weeks of age. Campylobacter coli numbers also spiked from near zero at week 9 to 8 X 107/g feces during week 12 (FEMS Microbiol Ecol 60:136-147 (2007)), leading to the hypothesis that the cecal microbiome modulates prevalence of foodborne pathogens in growing turkeys. Metagenomic sequencing analyses of composite bacterial genomic DNA as well as 16S rRNA genes in feces of grower-stage swine revealed significant shifts in species diversity and gene functionality correlating with dietary antibiotics. Recent investigations focus on a functional group of the swine intestinal microbiome -- butyrate-producing bacteria. Butyrate regulates inflammation, gene expression, and nutrition within colonic epithelial cells in humans, and we hypothesize that butyrate-producing bacteria contribute to a healthy intestinal ecosystem in swine. Preliminary investigations of bacteria from swine fecal, ileal, cecal, and colonic contents have revealed that butyrate-producing bacterial species in swine are more diverse than those reported for humans.