Development of a real-time PCR method forFirmicutesandBacteroidetesin faeces and its application to quantify intestinal population of obese and lean pigs

Abstract

Aims: To investigate whether the relative abundance of the Bacteroidetes and Firmicutes divisions in pigs is different between obese and lean animals. Methods and Results: Group‐specific primers were designed to target the 16S rRNA genes of Bacteroidetes and Firmicutes present in the gut. After the validation of their specificity, these primers were used in the real‐time PCR quantification of all Bacteria, Firmicutes division, Bacteroidetes division and Bacteroides spp. in the faecal samples of obese and lean pigs from Banna mini‐pig inbred line. The obese pigs had a ∼61% fewer percentage (based on all Bacteria) of Bacteroidetes division (P = 0·033) and a ∼56% fewer proportion of Bacteroides spp. (P = 0·047) than the lean pigs. The proportions of both Bacteroidetes and Bacteroides had a negative correlation (P < 0·01) with the body weight. Conclusion: The results suggested that the fat storage might affect the proportion of Bacteroidetes division in the gut. Significance and Impact of the Study: The real‐time PCR assays developed for Firmicutes and Bacteroidetes will be useful for investigating the composition of gut microbiota.

The effect of high-fat diet on the composition of the gut microbiota in cloned and non-cloned pigs of lean and obese phenotype

“…The same observations were made in the lean non-cloned pigs as compared with obese non-cloned pigs. These findings are in contrast with the findings in mice, 19 pigs 20 and humans, 21 where the lean individuals had higher abundance of Bacteroidetes compared with their obese counterparts. The lean animals in our study received HF/HE diet in restricted amounts and since they remained lean, the HF/HE diet could have affected the gut microbial community even in the absence of obesity and could explain the higher abundance of Firmicutes and lower abundance of Bacteroidetes.…”

Use of pigs as a potential model for research into dietary modulation of the human gut microbiota

“…in faecal samples appears to be much lower in the pig (0·1 % on average), in contrast to humans, where they belong to the frequently occurring bacteria (51,66) . On the other hand, according to Guo et al (2) , Bacteroides spp. averaged 3·8 % of total bacteria in faeces of 5-year-old (lean) Banna mini-pigs.…”

“…Still, the present, rather lean pig breeds will respond to a low-protein or high-fat diet by depositing more fat (190) . In this context, Guo et al (2) conducted a study with a Banna mini-pig inbred line, which shows pathological phenotypes of obesity and thinness. Lower numbers of Bacteriodetes in faecal samples were associated with normal rather than with obese pigs (Table 5) (2) .…”

“…In this context, Guo et al (2) conducted a study with a Banna mini-pig inbred line, which shows pathological phenotypes of obesity and thinness. Lower numbers of Bacteriodetes in faecal samples were associated with normal rather than with obese pigs (Table 5) (2) . These findings are in agreement with the results of a study with human participants, where obese subjects showed fewer numbers of Bacteroidetes and more Firmicutes compared with lean ones (191) .…”

“…The importance of the intestinal microbiota for gastrointestinal (GI) functions and health has been shown in many studies with human subjects, but also with model animals such as mice and pigs (1,2) . In addition, several disease patterns in humans may be associated with the composition and/or metabolic activity of the intestinal microbiota.…”