Effects Of Diet CEV/FEV On Intestinal Microflora Of Weaned Pigs

Carbohydrates and fat is an important energy of animal diets that has highly impact on physical health and performance of Animals.This study was used to explored the variation of of microbial flora of weaned piglets which were feed different CEV/FEV(Carbohydrate Energy Value /Fat Energy Value) diet, which would provide a basis for optimizing energy structure of piglets diet.Experiment I: This study was aim at investigating the influence of different diet Carbohydrate energy value and fat energy value rate(CEV/FEV) for the intestinal microbial and metabolites of weaned pigs. Experiment was designed as follows: Eighteen healthy pigs(Duroc × Landrace × Yorkshire) were randomly divided into three groups. Each group of CEV/FEV were: 11.7: 1.0(low fat group), 1.5: 1.0(mid fat group) and 1.0: 6.9(high fat group), and the digestible energy were all 14.6MJ / kg, protein levels were all 17%.The PH, Volatile fatty acid,NH3-N,number of bifidobacteria, lactobacilli, E.coli of weaned pig’s gut were purified by the method of colorimetry, gas chromatography, and by the method of traditional microbiological culture. The results showed that: With the reduction of CEV/FEV, pH was significantly increased(P <0.05); VFA concentrations significantly reduced(P <0.05), NH3-N were significantly increased(P <0.05); while, the number of E. coli significantly increased(P <0.05), lactobacilli and bifidobacteria was significantly reduced(P <0.05). To improve the CEV/FEV of diet is conducive to the proliferation of beneficial bacteria, inhibit the proliferation of harmful bacteria; It has contribution to keep the microecological environment balance of intestine.Experiment II: Effects of CEV/FEV rate on gastrointestinal microflora diversity of weaned piglets. The microbial total DNA of piglets was extracted by the method of phenol. DNA was detected by DNA quantitative detection instrument and gel electrophoresis. The results showed that: the fragment of DNA about 23000 bp, concentration of OD260/OD280 is between 1.7 and 2.0, purity is better. DNA was amplified by PCR and the amplified products were similarity analysed and Gel extractied sequence after the DGGE. The DGGE mapping results show that the number of caecum microorganism bands which were separated by PCR-DGGE more than colon; The similarities within species of cecum of low fat group were noticeably higher than 83%; the similarities between species of cecum were 68%. The similarities within species of coloc were up to 77%, and the similarties between species is lower. The similarties among medium group and others. The results revealed that the difference of microbial community structure among groups is higher. The dominant bacteria were Uncultured bacterium, Ruminococcus sp, Coprococcus catus of cecum and colon in weaned piglets When the CEV/FEV ratio of dietary was 11.7:1.0. Apparently, high diet CEV/FEV were more beneficial for intestinal microorganism growth of weaned pigs.In conclusion, diet Carbohydrate energy value and fat energy value rate(CEV/FEV) will affect the intestinal microbial community structure of weaned piglets in different degree. It’s conducive to the proliferation of beneficial bacteria and rich microbial diversity of cecum and colon when the diet CEV/FEV was 11.7:1.0. Therefore, increasing dietary carbohydrate / fat ratio is conducive to improving the intestinal tract of weaned piglets micro ecological environment, maintain intestinal health and microbial community structure. These results have an important significance to further optimize the energy structure of piglets and to explore the digestion, absorption and utilizing system of different enengy carrier in piglets.