Research And Development Of Composite Probiotics In Pig Intestinal

In theory, the digestive tract in newly born animal still remains sterile and the initial inocula of microbiota from environment significantly affect the composition and development of the animal gut microbiota. As the result, the different composition of gut microbiota influences the development of the digestive system and the maturation of the immune system through the alternation of the gene expression in intestinal epithelium cells in animals. On the other hand, the genetic background of animals also plays a crucial role in the selection of gut microbiota during the colonization. Once the harmonic relationship established between the host and their gut microbiota, the host becomes a complicated super-biological-organism. Therefore, it has been widely accepted that the gut microbiota play a crucial role in the maintenance of the host health. Since the microbiota species in the animal gut is extremely complex, composing of more than thousand species, a new generation of probiotics should be a mixture of complex microbiota community rather than just simply containing two or three bacterial species such as bacillus and lactic acid bacteria. Therefore, this paper attempts to study the development of more function and more stable compound probiotics, the following is the research content and results.The first step, culture medium choice:Since the gut microbiota composition can be influenced by several factors such as age, dietary composition and the host genetic background, the bacterial community structures in the individual host differ significantly between each other, thus an in vitro gut model system has been established in the current study in order to produce a large quality of stabilized products with desirable bacterial compositions. In addition, because it is desirable to have the composition of bacterial inocula similar to the microbiota composition in the animal gut, the composition of growth medium in the chemostat systems was initially tested. In order to make a right composition for growth medium, we measured the nutrient composition in the contents of pig intestinal tract including the terminal ileum, colon and feces. A reasonable medium composition was set up based on the ratio of carbon to nitrogen (C/N) in the pig terminal ileum and chemostat experiments. With this VL medium composition.The second step, inoculums selective:Compare two pig head strong and content of bacteria resistant, pathogenic bacteria, select the low resistance, no salmonella pig gut content to inocula, A large quality of bacterial products was produced in the in vitro chemostat system and the ability of the colonization in the newborn piglets was tested.The third step, animal experiment and results:Probiotic bacteria feeding newborn piglets, through the DGGE and Real-time PCR analysis shows that, feeding composite probiotics can greatly affect bacterium group structure, raise pig gut Provotella content, and promote the pig growth. Expect alternative used to prevent intestinal bacterial disease of antibiotic, so as to reduce the abuse of antibiotics.