Denaturing gradient gel electrophoresis (DGGE)-based monitoring of intestinal lactobacilli and bifidobacteria of pigs during a feeding trial.

The aim of this study was to determine the influence of different feeding strategies on the gut microbiota of organic growing-finishing pigs. A total of 76 pigs were allocated to four different dietary treatments (control, probiotics, maize silage and grass silage). Effects of the applied probiotic preparation on the composition of the intestinal and faecal microbiota were monitored. By using a DGGE (denaturing gradient gel electrophoresis)-based methodology, fingerprints of the intestinal microbiota were obtained. The total microbial DNA was isolated from faecal and colon samples and amplified with PCR using different primer sets to detect bifidobacteria and lactobacilli. PCR products were separated using DGGE and the resulting profiles were compared with the findings of the other dietary treatments. Bands were excised from the gels and sequenced for further identification. Particularly two different DGGE profiles of bifidobacteria were observed, while lactobacilli showed larger variety within the dietary treatments.