Study On The Quantitive Relationship Between Xylanase Supplementation And Energy Feeds

This study contain three trial: vitro trial, metabolic trial and growth trial.1. The vitro trial was conducted to measure the levels of total pentosan and water soluble pentosan in four energy feeds (corn, wheat, wheat bran and 'rice bran)from different sources and to test the effects of xylanase on the total pentosan and water soluble pentosan of four energy feeds in vitro, in order to establish the quantitive relationship between xylanase level and corn,wheat,wheat bran and rice bran. Four single-factor experiment designs were employed. Every feed ingredient was incubated with 6 different xylase level with 6 replicates respectively. The results showed that: both total pentosan and water soluble pentosan levels were influenced by the kind and source of feeds. The total pentosan of corn, wheat, wheat bran and rice bran were respectively 3.87%, 7.11%, 20.24% and 9.90%; The water soluble pentosan of corn, wheat, wheat bran and rice bran were respectively 0.11%, 0.85%, 0.92% and 0.15%. The disaggregate effects of xylanase on total pentosan and water soluble pentosan were different in feeds with the largest effects on wheat and wheat bran, then least effects on rice bran. The appropriate dietary xylanase levels for corn, wheat, wheat bran and rice bran were 34.88, 25.74, 11.59 and 8.9 IU based on 1 gram total pentosan or 1000, 251.07, 616.32 and 555.56 IU based on 1 gram water soluble pentosan respectively.2. The metabolic trial was conducted to test the effects of xylanase on the nutrients digestibility and AME of four energy feeds (corn, wheat, wheat bran, rice bran), inorder to establish quantitive relationship between xylanase supplementation and corn,wheat,wheat bran and rice bran. Four single-factor experiment designs were employed. Every base diet was treated with 5 different xylanase level, eight replicate cages of 1 broiler were assigned to each treatment. The results showed as follows: compared with control, supplementation with 1500 or 2000IU xylanase to corn increase DM digestibility 0.93% (P＜0.05) or 0.82% (P＜0.05) respectively, supplementation with 1000, 2000, 3000 or 4000IU xylanase to wheat increase DM digestibility 5.71% (P＜0.01),5.72% (P＜0.01),7.03% (P＜0.01) or 4.44% (P＜0.05), increase energy digestibility 5.55% (P＜0.01),5.3% (P＜0.0i),6.78% (P＜0.01) or 3.63% (P＜0.05) respectively; supplementation with 1000IU xylanase increase wheat fat digestibility 7.01% (P＜0.05) and supplementation with 3000IU xylanase increase wheat protein digestibility 22.31% (P＜0.05). supplementation with 2000,4000,6000,8000IU xylanase to wheat bran increase DM digestibility 2.41% (P＞0.05),8.30% (P＜0.01),10.14% (P＜0.01),7.59% (P＜0.05), energy digestibility 6.45% (P＜0.05),11.24% (P＜0.01),14.74% (P＜0.01),12.76% (P＜0.01) and protien digestibility 68.95% (P＞0.05),157.24% (P＜0.01),95.45% (P＞0.05),109.40% (P＜0.05) respectively. supplementation with 1500IU xylanase to rice bran increase protein digestibility 27.94% (P＜0.05 ). Supplementation xylanase increase AME values of wheat and wheat bran significantly. The results suggest that The appropriate dietary xylanase levels for corn, wheat, wheat bran and rice bran were 35.37, 27.01, 30.21 and 18.27 IU based on 1 gram total pentosan or 1250, 273.56, 753.33 and 937.5 IU based on 1 gram water soluble pentosan respectively.3. The growth trial was conducted to check the quantitive relationship between xylanase supplementation and corn or wheat. Tow single-factor experiment designs were employed. Every base diet was treated with 4 different xylanase level and 6 replicate cages of 20 broilers were assigned to each treatment. The results showed as follows: The xylanase supplementation level to corn or wheat was suitable; Supplementation xylanase has no significant effect on growth performance of bioilers fed corn-soybean diet, but may improve broilers growth performance fed wheat-soybean diet significantly.