Effects Of Cold Stress On Gut Mucosal Immune Of Chicken

Studies have demonstrated that many tissues and organs could be affected by cold stress, and immune system could be affected by cold stress significantly. Intestinal tracts were not only degestive organs but also immune organs, the function of intestinal tracts has a directive relationship with the health of animals, however, the studies about gut mucosal immune and cold stress were less seen. So this study was done. As the experimental animals, chickens were treated with acute and chronic cold stress (12±1℃) to investigate the effects of cold stress on gut mucosal immune function of chickens in order to provide the scientific data for studying the mechanism of the effect of cold stress on gut mucosal immune system in chickems. Some items about the expression and content of IFN-γ, HSP70, PPAR-γand so on in duodenum, jejunum, ileum and cecum were detected. The results showed as follows:1. Through the observation of ileum and cecal tonsil in microscope, it is proved that the cold stress can cause histopathological changes of cecal tonsil.2. Through the detection of the expression and content of cytokines in duodenum, jejunum, ileum and cecum, it was demonstrated that both acute and chronic cold stress could influence the expression of IFN-γ, IL-2, IL-4, IL-6, IL-7 and IL-17 in duodenum, jejunum, ileum and cecum. These indicated that the cell immunity was more important at the end of acute cold stress, the humoral immunity the cell immunity played roles in other duration of cold stress together.3. Through the detection of the expression of HSP70, it was demonstrated that the expression of HSP70 was increased in duodenum, jejunum, ileum and cecum during the beginning of acute and chronic cold stress. It was indicated that the organism can resist the damage in chicken's duodenum caused by cold stress by this approach..4. Through the detection of the expression level of PPAR-γmRNA in duodenum, jejunum, ileum and cecum, the results indicated that both acute and chronic cold stress could alter the mRNA levels of PPAR-γgene in duodenum, jejunum, ileum and cecum. This indicated that PPAR-γplayed an important role in the gut mucosal immune in chickens during cold stress.5. Through the detection of the expression level of SeW RNA in duodenum, jejunum, ileum and cecum, the results indicated that both acute and chronic cold stress could alter the mRNA levels of SeW gene in duodenum, jejunum, ileum and cecum. It was indicated that the organism can resist the damage in chicken's duodenum caused by cold stress by this approach.In this study, we preliminarily reveals the mechanisms of cold stress on chicken's gut mucosal immune function in duodenum jejunum, ileum and cecum and the resistant mechanism of intestines to cold stress through observing aspects about the changes in morphologic structure, the contents and expressions of cytokines and the immune regulation.Our aim is to explore methods which can improve animal's cold-resist ability so as to provide a scientific basis and experimental foundation for maintaining animals'normal physiological functions in cold stress environments.