Effects Of Compound Enzyme Preparation On Nutritional Regulation And Intestinal Health Of Broiler Chickens

In order to confirm the quality of enzyme preparation and provide effective data support for the practical application in livestock and poultry industry in the future,the following studies were conducted with broiler chickens as the entry point of this study.First of all,this experiment adopts a three-factor experiment design.2×2×3 conducts experiments at two temperatures of75 ℃ and 85 ℃ and three time gradients of 30 s,60 s and 90 s for 4 replicates in each group.The activities of amylase,protease,cellulase and phytic acid in different compound enzymes were detected.The effects of amylase,protease,cellulase and phytase levels on growth,nutrition metabolism,immune function and intestinal health of Ross broiler chickens were studied in a single-factor completely randomized trial design.The diets were divided into the positive control group and the negative control group,and the enzyme preparations were added to the negative control group.A total of 468 1-day-old healthy Ross broiler chickens were selected and randomly divided into 6 groups with 6 replicates in each group.The amount of dietary compound enzyme preparation added in each group was 200 g/t.The experiment was conducted at 3 and 6 weeks of age for slaughter test and nutrition index detection,and the growth performance of broiler chickens was tested weekly.Finally,the metabolic rate of nutrients,blood indexes,immune organs,intestinal development and morphology,and intestinal microflora were measured to screen out a group of compound enzyme preparations with the best effect.The research results show that:(1)At room temperature,the enzyme activity of the enzyme preparation group IV was higher than that of the other groups.The activity of amylase was the best when it was treated at85 ℃ for 30 s during heating.Among them,the inactivation rate of amylase in group III was the lowest;the heat resistance of cellulase was stronger in groups I and II;phytase was kept at a constant temperature of 37 ℃ The lower group IV had the highest phytase activity,the lowest group I,and the highest heat inactivation rate in group I,and the lowest enzyme inactivation rate in group IV;the protease activity was the highest in group IV and the lowest in group II at 37 ℃.After heat treatment,group II had the highest inactivation rate,and group IV had the lowest enzyme inactivation rate.(2)The compound enzyme preparation had no effect on the growth performance of broilersat 1-2 weeks of age(P>0.05).At 6 weeks of age,the average daily feed intake and average daily gain of broilers could be significantly increased(P<0.05).Compound enzyme preparation can effectively increase the metabolic rate of broilers to P,DM,NDF.Compared with the negative control group,only the enzyme preparation group IV has an effect on Ca,P,CP,DM,ADF,NDF.Compared with the negative control group at the age of 3 weeks,CP,Ca,P,DM,NDF and ADF were increased by 10.45%,13.93%,12.78%,7.00%,15.87% and 26.27% respectively;compared with the positive control CP,Ca,P,DM,NDF and ADF increased by 6.92%,7.95%,9.97%,3.71%,5.03% and 13.02% respectively.At 6 weeks of age,CP,Ca,P,DM,NDF,and ADF were increased by 3.67%,13.73%,15.27%,5.74%,20.32%,and 32.03% compared to the negative control group;CP,Ca,P,DM,NDF,and ADF were increased by 8.18%,5.32%,5.76%,2.09%,1.50%,and 15.30%,respectively.Compound enzyme preparation can improve the blood index content of broilers.The digestibility of calcium of group IV compound enzyme preparation at 3weeks of age increased by 9.36% compared with the negative control group,but the difference was not significant(P>0.05).The content of P,TP,ALB and GLU were significantly increased,and the content of UA was significantly reduced(P<0.05).The blood index content of broiler chickens in other enzyme preparation groups also improved correspondingly,but there was no significant difference compared with the control group(P>0.05).(3)The compound enzyme preparation has no effect on the slaughter rate of broilers(P>0.05).Compared with the negative control group,the four enzyme preparation groups and the positive control group can significantly improve the broiler semi-clear rate,full-clear rate and breast muscle rate And leg muscle rate(P<0.05).Compared with the negative control group,the four compound enzyme preparation groups and the positive control group can significantly increase the bursal index(P<0.05).Among them,the enzyme preparations Ⅰ,Ⅱ,and Ⅲ groups compared with the two control groups.The spleen index,thymus index and bursa index had no effect(P>0.05).The enzyme preparation Ⅵ group significantly improved all the indicators(P<0.05).(4)Compared with the negative control group,the four compound enzyme preparation groups and the positive control can effectively increase the villi height of the duodenum,jejunum,and ileum(P<0.05),and can effectively reduce the depth of the crypts of the duodenum and ileum(P<0.05).The ratio of the duodenum to the ileum at 6 weeks of age;compared with thenegative control group,the four compound enzyme preparation groups can significantly increase the number of lactobacilli and bifidobacteria in the ileum and cecum of broilers(P<0.05).Significantly reduce the number of E.coli(P<0.05).Conclusion: Feeding enzyme preparations can regulate broiler nutritional levels,immune function and improve intestinal health,improve the utilization of nutrients in feed by broilers,and ensure the healthy development of the intestinal tract of broilers.The effect is the best.