Effects Of Casein Hydrolysate And Insulin On The Gastric And Pancreatic Growth And Development Of IUGR Pigs

In order to investigate the effects of casein hydrolysate and insulin on the growth and development of stomach and pancreas in intrauterine growth retardation (IUGR) piglets, the experiment compared the difference of tissue weight, content of protein, DNA and RNA, activities of digestive enzymes in stomach and pancreas, gastric histological and morphological parameters, and content of insulin and glucagon in pancreas among newborn piglets, piglets bottle-fed for 3 days with cow-milk and cow milk supplemented with insulin, casein or casein hydrolysate.In the first experiment, thirty Sutai piglets were selected from five litters, three normal weight piglets (NW) and three IUGR piglets from every litter, and divided into three groups: newborn group(N), casein group(C) and casein hydrolysate group(CH), five normal piglets and five IUGR piglets in every group. The piglets in group C and CH were fed milk substituted 1.5% casein and 1.5% hydrolysed casein solution for 10% (v/v) milk for 3 days, respectively. Compared with group N, weight, content of protein, DNA and RNA, total proteolytic activity of protease in stomach of piglets bottle-fed for 3 days was increased significantly (P<0.05) , but total milk-clotting activity of gastric protease was decreased (P<0.05) , histological and morphological parameters had no significant changes. Gastric protein content and total milk-clotting activity of protease of group CH normal piglets, and protein content, the ratio of protein to DNA, and total milk-clotting activity of protease in stomach of group CH IUGR piglets were all higher than those of group C (P<0.05 ) .After the piglets were fed artificially for 3 days, tissue weight, content of protein, DNA, RNA and glucagon, total activities of amylase and lipase in pancreas were all increased ( P<0.05 ), while total activities of trypsin were decreased significantly (P<0.01 ). Compared with C group, pancreatic content of protein and DNA in normal group CH piglets were increased significantly (P<0.05 ), and total activities of chymotrypsin, the ratio of chymotrypsin activities to trypsin activities in group CH IUGR piglets were also increased (P<0.05) . The results show that great changes took place in tissue weight, morphological and activities of digestive enzymes in stomach and pancreas of normal and IUGR piglets during the early postnatal period. And casein hydrolysate could stimulate gastric protein synthesis and improve the activity of total milk-clotting activities of gastric proteases in normal and IUGR piglets. Moreover casein hydrolysate could stimulate the proliferation of cells, protein synthesis in pancreas of normal piglets , and increase theactivity of chymotrypsin in IUGR piglets.In the second experiment, thirty Sutai piglets were selected from five litters, three normal weight piglets (NW) and three IUGR piglets from every litter, and allotted to three groups: newborn group(N), milk group(M) and milk supplemented with insulin (60IU/L) group(I), five normal piglets and five IUGR piglets in every group. After the piglets were fed artificially for 3 days, gastric tissue weight, content of protein, DNA and RNA were increased at different degrees, but total milk-clotting activities of gastric protease was dereased(P<0.01), no remarkable changes were found in total proteolytic activity of gastric protease and gastric morphological parameters (P>0.05 ). Compared with group M, content of protein and DNA in stomach of group I normal piglets, and gastric protein content of IUGR piglets in group I were increased obviously (p<0.05) , gastric relative weight, concentration of protein, DNA and RNA, the ratio of protein to DNA in the stomach of normal and IUGR piglets in group I were higher (P>0.05) , the differences in total milk-clotting and proteolytic activities of gastric protease between group M and group I didn't reach the significant level of statistics (P>0.05 ) .Compared with newborn group, pancreatic tissue weight, contents of protein, DNA and RNA, total activities of amylase and lipase in bottled-fed piglets were higher,...