The Effect Of Selenium Deficiency On Intestinal Mucosal Morphology And Mucosal Immune Function In Chick

Selenium is an essential trace element for growth and development of animals and humans. Selenium deficiency causes occurrence of many diseases in chicks, of which diarrhea is one of main clinical manifestations. The diarrhea in chickens is associated with morphology and immune function of intestinal mucosa. In order to investigate the effect of selenium deficiency on intestinal mucosa, the indexes regarding growth perfomance, intestinal mucosal morphology, and the cells associated with mucosal immune were detected and analyzed in the chicks suffering from selenium deficiency.120 chickens(1 day old, male three yellow broiler chicks) were randomly divided into two groups. The experimental animals were maintained either on Se-deficient granulated diet or control group of the commercial granulated diet. The experimental samples of duodenum, jejunum, ileum, colon, and rectum were collected from experimental chicks at 10, 20 and 30 days old, respectively. The hematoxylin-eosin staining was used to detect morphology of intestine mucus, the number of epithelial lymphocytes and epithelial goblet cells in duodenum, jejunum, ileum, colon and rectum, the number of epithelial lymphocytes and epithelial goblet cells, toluidine blue staining was applied to detect the number of mast cells in the intestinal mucosa, ELISA was applied to detect the level of SIgA and SS.The results :(1) Selenium Deficiency test group chickens compared with the control group, the test of the first 10 d body weight were significantly different(P<0.05), Section 20 d, 30 d body weight differences were highly significant(P>0.05); in section 10 d, 20 d, when the 30 d, thymus, pancreas, bursa, liver, immune organs and organ coefficient differences were highly significant(P<0.01). In the first 10 d, spleen organ coefficients were not significant(P>0.05), Section 20 d, 30 d when the difference was significant(P<0.01),(2) the lack of selenium test group chickens duodenum, jejunum, ileum, cecum, rectal villus length, have varying degrees of reduced villus width and crypt depth and muscular thickness, V / C value compared with the control group, in the first test of the 30 d was significantly different(P<0.01), which duodenum, jejunum, ileum is particularly evident.(3) the lack of selenium test group chickens duodenum, jejunum, ileum, cecum, rectal intraepithelial lymphocyte count decreased, significantly reduced(P<0.01) in the test section 30 d of the time; the number of goblet cells in the epithelium Early tests did not change significantly during the test of the first 30 d decreased significant(P<0.05); significantly increased(P<0.01) when the amount of mast cells in the test of the first 30d; 30 d in the first trial period, mucosa SIgA significantly reduce the content(P<0.01), SS were significantly increased(P<0.01).In conclusion, Selenium deficiency influenced growth performance through decreasing daily gain,feed gain ratio, immune organ index; selenium deficiency decreased length and width of villus, crypt depth, intestinal muscular thickness and the value of V/C; The damage of intestinal mucosa in normal intestinal mucosa decreased the intestinal mechanical immunity; Selenium deficiency can get the number of Intraepithelial lymphocytes, Goblet cell, Mast cell, Secreted immunoglobulin A, Somatostatin changing, result intestinal mucosal immunity lower of chicks...