Abstract: In order to explore the effect of high fat diet on mouse intestinal flora, the composition of intestinal flora in mice fed high fat diet as the obesity model and normal diet as the control were analyzed by conventional cultivation method and fluorescence in situ hybridization (FISH). The results indicated that the obesity model group had a significantly heavier body weight than the control group (P ＜ 0.01). The change trend of intestinal microflora evaluated by FISH was consistent with that determined by conventional cultivation method; however, the number of bacteria determined by FISH was obviously higher than that from conventional cultivation method. The numbers of Bifidobacterium, Lactobacillus and Enterococcus revealed an obvious decrease (P ＜ 0.01), and the number of Enterobacteriaceae revealed an obvious increase (P ＜ 0.05) in the obesity group compared with the control group. Therefore, high fat diet can greatly alter the structure of intestinal flora, resulting in a low-grade inflammation and induce the development of obesity.

Key words: high-fat diet, intestinal flora, obesity, fluorescent in situ hybridization (FISH)