Study On Development Of Digestive Enzymes, Digestive Tract Histology And Exogenous Enzyme Supplementation In Rex Rabbits

A series of seven trials were conducted to investigate the effects of ages, the different nutrition level of diets and exogenous enzymes supplementation on activities of enzymes in digestive tract and intestinal morphology, blood biochemistry parameters, nutrients digestibility, production performance and meat quality in Rex Rabbits. The results were summarized as follows:1. Study on the development of digesta pH and main digestive enzymes in digestive tractObjective: To detemine the development of digesta pH and main digestive enzymes in digestive tract.Methods: Using the Rex rabbits that reared in the same farm and fed same diet. The rabbits were slaughtered from newborn to adult. The digesta pH, activeties of digestive enzymes in digestive tract and that in pancreas were analyzed and compared.Results: (1) The content of duodenum was weak acidity,and that of jejunum was change from weak acidity to weak base,however that of ileum was weak base and that of cecum was acdity. (2) The amylase activity expressed per g of digesta in jejunum was highter than that of duodenum and ileum (P<0. 05),but the difference of amylase activity between duodenum and ileum was insignificantly(P>0.05).The activity of amylase in cecum was lower than that in small intestine.Weaning decreased the amylase activity in small intestine affect slightly in cecum (P>0. 05). (3)With the daily increased, the trypsin activity had a tendency to increase, and the trypsin activity were: jejunum>ileum> doudenu.. weaning decrease the trypsin activity in doudenu (P<0.05), jejunum and ileum and cecum (P>0.05) (4) With the daily increased before 8 weeks, the chymotrypsin activity was increased and the activity of chymotrypsin were jejunum > ileum > doudenu,and became a constant after 8 weeks. The changes of chymotrypsin activity was similar to that in small intestine. The effect of weaning on chymotrypsin activity was similar to trypsin's,there was no significient change in weaning and in chymotrypsin activity in cecum. (5) With the daily increased, the change of lipase activity was similar to chymotrypsin and trypsin.Weaning decreased the lipase activity in duodenum and ileum but did not affect jejunum and cecum.(6)The lactase activity had decreased when the age increased ,there was lost in adult.and the activity were: jejunum>doudenu>ileum.(7) With the daily increased before 12 weeks, the cellulose activity in cecum had increased. and became stable (constant) after 12 weeks. Weaning increased the cellulose activity in cecum (P<0. 01).(8)The digestive enzyme activity in pancreas increased with increasing the age. Weaning decreased the activities of trypsin,chymotrypsin lipase and amylase in...