EN
The impact of diet on the microbial
composition in the gastrointestinal tract (GIT) has been
well documented. However, quantifying the role of
the diet in shaping microbial composition in humans
has been difficult due to the influence of host genetics
and the environment. To test the influence of diets on
the GIT microbiome independently of host genotype
and environment, two genetically identical co-housed
pigs were used in an A-B-A-B design across four 14-day
periods using two distinct diets that differed in dietary
fiber source, soybean hulls or wheat bran. Shifts in
fecal microbiomes were assessed with respect to dietary
changes by 454-pyrosequencing analysis using the V3
region of the 16S rRNA genes. Similarity analysis revealed
that the GIT microbiome distinctly clustered by diets
rather than by individual. Diversity analysis showed that
the diet fed had an influence on GIT microbiome diversity,
which was host specific. While many bacterial taxa and
KEGG orthologs reacted similarly to switches in diet, some
bacterial taxa and KEGG orthologs reacted differentially in
each of the pigs. While diet changed the GIT microbiome
composition of isogenic co-housed pigs, inter-individual
variations from epigenetics were not entirely eliminated
by the use of cloned pigs.