Study On The Effects Of Pectinase On The Nutrition Utilization Of Corn-soybean Meal Diet In Broilers

Using both vitro digestion methods and intro methods to study the effect of pectinase on the nutrition utilization of corn-soybean meal diet in broilers.In vitro digestion trial, the content of pectin and galacturonic acid in soybean meal was measured; the activity of pectinase was measured according to two kinds of pectinase unit definition; under these two kinds of pectinase unit definition ,the effect of different pectinase level on the dry matter digestion rate, the content of reducing sugar and viscosity of the soybean meal was studied in order to ascertain the optimize dose of pectinase (U/g soybean meal) in vitro digestion methods. The result showed: the pectin content of soybean meal was 10.45%, and the galacturoninc acid content was 7.64%; the activity of pectinase was 12781.25U/g and 1234.3 8U/g respectively according two kinds of pectinase unit definitionjthe pectinase can improve the dry matter digestion rate and the content of reducing sugar of the soybean meal, but it had no effect on the viscosity; under the condition of pH 4.2 and 40 C,the optimize dose of pectinase was 4.6-6.2U/g(soybean meal).840 AA broilers were randomly allocated to 7 dietary groups and replicated 5 times, which had 24 broilers, to study the effect of pectinase levels on the broilers performance and digestion function. Treatments' diets of 0-21 days supplemented with pectinase at 0.001%, 0.005%, 0.025%, 0.125%, 0.2%, 0.275%, and 21-42 days treatments's diets with 0.0008%, 0.004%, 0.02%, 0.02%, 0.1%, 0.016%, 0.022%. The results showed: (1) Supplementd with pectinase improved the broiler performance of 0~21days (p<0.05) and inclined to improve the broiler performance of 21-42 days(p>0.05). Supplemented with 0.025% pectinase in the diets of 0-21 days is the optimize dose, as well as the 0.02% pectinase in 21-42 days diets. (2) Supplemented with pectinase significant increased the digestibility of dry matter, crude protein and crude fibre(p<0.05), inclined to improve the energy metabolizable rate and digestibility of the crude ash(p>0.05), didn't affect the digestibility of the crude fat. The effect of pectinase on the Ca and P are irregular with the pectinase levels and need further research. (3)The pectinase levels did't affect the jejunum amylase, but the duodenum amylase, proteolytic enzyme and jejunum proteolytic enzymeinclined to significantly improve first (p<0.05), then the increasing extent decreased.(4)The pectinase significant decrease the chyme viscosity of duodenum and jejunum(p<0.05) but had no effect on the chyme viscosity of ileum(p>.05).