Intestinal microbiota in growing pigs: Effects of stocking density

Abstract

This study aimed to assess oxidative stress and microbiota in pigs at different stocking densities. Markers for oxidative stress were investigated and gut bacteria identified. The pigs were randomly assigned to high-, medium- or low-density groups. The results showed that the superoxide dismutase (SOD) levels in the high- and low-density groups were lower than in the medium-density group. Glutathione peroxidase (GSH-Px) activity was significantly lower in the low-density group and highest in the medium-density group. We found no discrepancies between estimators of bacterial richness across the three groups. The jejunum and ileum were mainly occupied by Firmicutes and Proteobacteria of the classes Bacilli, Clostridia, Erysipelotrichia and Gammaproteobacteria. The ceacum was mainly occupied by Bacteroidetes and Firmicutes of the classes Bacteroidetes, Clostridia and Negativicutes. The results revealed that gut flora was not affected by stocking density. However, stocking density may influence oxidative stress.