The Effects Of Different Enzyme Preparation On The Ileal Nutrient Digestibility And The Mechanisms In Broilers

The experiment was to study the effects of different enzyme preparations on the performance, digestive tract structure and function of broilers, and ileal digestibility of diets based on the corn-soybean meal-cotton seed meal-rapeseed meal diet with low nutrient level. Three hundred eighty-four 7-old chicks were randomly divided into 8 groups with 8 replicates of 6 birds, 4 replicates of male and 4 replicates of female. Treatment 8 was the control fed basal diet. Treatments 1 to 7 were fed diets with addition of 7 different enzyme preparations in basal diet. Enzymel contained xylanase 1400u/g, beta-glucanase 2000u/g;enzyme 2 contained xylanase 1000u/g, amylase 2300u/g, protease 5000u/g; enzyme 3 contained xylanase 350u/g, amylase 1800ulg .protease 4000u/g; enzyme 4 contained mannase 7200u/ml;enzyme 5 contained xylanase 600u/g, amylase 800u/g, protease 8000u/g; enzyme 6 contained xylanase 4300u/g, amylase 400u/g , protease 4000u/g and enzyme 7 contained xylanse 8000u/g. The feed trial lasted 14 days. At 21d of age , 0. 4%chromic oxide was added to the diets. On 25d old, all chicks were sacrificed by cervical dislocation to collect duodenum, jejunum and ileal contents and the middle of jejunum . Ileal digesta were freeze-dried for measuring digestibility of nutrients. The other gastrointestinal contents were used to measure the activity of some endogenous enzyme or digestive tract structure. The results were that the average body weight gain of 7—21d broiers were improved in some extent with the addition of enzyme preparartions, while the feed intake and feed/gain were decreased(p>0. 05). Ileal CP digesitibility...