Impact of Diet on Swine fecal microbiome

 

Distillers dried grain (DDGS) is a byproduct of ethanol industry and is an economical source of energy, protein and phosphorous in swine diets. This study was aimed at ascertaining the potential effect of DDGs on gut bacteria.  Pigs were fed one of four diets containing 0, 10, 20 or 40% DDGS. Fecal samples were collected, on week 3 of a 4 week cycle for bacterial analysis. Total DNA was extracted from the fecal samples and the diversity and composition of the hindgut bacterial flora between different dietary treatments were assessed using high throughput sequence analysis.  The vast majority of the sequences were from the phyla Firmicutes and Bacteroidetes. The relative ratios of Firmicutes to Bacteroidetes were higher in control diet (~5:1) compared to the DGGS supplemented diets (Avg. ~1:1). The bacterial diversity in the 40% DGGS supplemented diet was highest compared to the other two diets.  Animals fed with the control diet had relatively high numbers of lactic acid bacteria (Streptococcus and Lactobacillus). However, with 20% and 40% DGGS diets the Bacteroidetes bacteria, mainly the genus Prevotella, increased over the lactic acid bacteria. The genus Streptococcus was not detected in animals fed with 40% DGGS diet.  We did not find any evidence that high amounts of dietary sulfur, as in 40% DGGS diet, has an adverse effect on gut bacteria since we observed a more diverse bacterial population in the animals fed 40% DGGS compared to control animals.