Study On Correlation Between Small Intestine Starch Content And Pancreatic Amylase Secretion In Dairy Cows

This test analyzed the content of small intestine starch and apparent digestibility,body conditions,and lactation by injecting 0g/d,500g/d,1000g/d,1500g/d,and 2000g/d starches into the duodenum of Hostan cows.function,And the relationship between the secretion of pancreatic amylase,for the scientific establishment of cow feed formula,to increase milk production to provide experimental basis.The main findings are as follows:1.Injecting different concentrations of starch into the small intestine of cows does not affect the amount of dry matter harvested by cows(P>0.05)However,it has a certain effect on the intake of digestive energy,net lactation energy,and body weight and body condition score of cows(P>0.05).With the increase of starch intake,the content of digestive energy intake and lactation net energy increased in a straight line,while the content of digestive energy intake and lactation net energy was highest when the starch perfusion reached 2000 g/d.2.Injecting different concentrations of starch into the small intestine of cows does not affect the apparent digestive rate of cow dry matter,organic matter,crude protein,neutral washing fiber,and acidic washing fiber(P>0.05).However,with the increase of starch perfusion level,the starch digestibility of the test cow was greatly affected.Under the starch perfusion condition of 500g/d,the starch apparent digestibility of the test cow reached 90.48 %,but the difference was not significant(P>0.05)With the increase of starch content,the apparent digestion rate of starch gradually decreased.When the starch perfusion condition of 2000g/d was only 78.21 %,compared with the unperfusion starch group,it decreased by 10 points.Significant differences(P>0.05).3.Infusion of different concentrations of starch into the small intestine of cows does not affect the milk production of cows,and changes in milk protein production and milk protein rate(P>0.05),but it affects the proportion of milk fat,lactose,and milk fat and lactose in the milk component.With the increase of starch perfusion,the milk fat content appears to increase,reaching the highest at 1500 g/d starch.However,it was reduced under 2000 g/d starch perfusion conditions.With the increase of starch content,the lactose content and its proportion all show a linear upward trend(P>0.05)At 2000 g/d starch perfusion,the lactose content reached 822.63 g/d,which was significantly higher than 752.15 g/d(P>0.05).Analysis of the composition variation ratio of milk showed that the lactose content was significantly higher than the milk fat content,and the milk fat content was significantly higher than the milk protein content,with significant differences(P>0.05).4.Infusion of different levels of starch into the small intestine of cows has a significant effect on the secretion concentration and synthesis rate of pancreatic alpha-amylase(P>0.05).The experiment found that the secretion concentration and synthesis rate of pancreatic ?-amylase showed a tendency to increase and then decrease with the increase of starch level,and showed a higher level at 1000g/d and 1500g/d.It shows that certain levels of starch can stimulate the secretion of alpha amylase in the pancreas.