【作者】 王兆钧；

【导师】 王春维；

【作者基本信息】 武汉工业学院 ， 动物营养与饲料科学， 2011， 硕士

【摘要】 本试验以废啤酒酵母为原料,探讨高压均质-酶碱法制备酵母β-葡聚糖的最佳工艺条件,并研究酵母β-葡聚糖对饲喂霉变玉米日粮肉仔鸡生长性能、器官指数及血清指标的影响。试验分为两个部分:试验一酵母β-葡聚糖制备的工艺条件研究本试验采用高压均质与酶碱法相结合的方法制备酵母β-葡聚糖,以多糖纯度为评价指标,确定最佳工艺条件为:将浓度为15%的酵母悬浊液高压均质处理后,离心收集沉淀,按120 U/g酵母细胞壁残渣添加木瓜蛋白酶,pH6.0、55℃酶解6 h后离心,以2 ml/g沉淀物加入3%NaOH溶液,90℃处理2 h,水洗至中性,离心后沉淀物37℃烘干。此条件下多糖得率10.5%,多糖纯度为85.4%。试验二霉变日粮中添加酵母葡聚糖对肉仔鸡生长性能、器官指数及血清指标的影响本试验旨在研究酵母β-葡聚糖对饲喂霉变日粮肉仔鸡生长性能、血清指标及器官指数的影响。选用180只体重接近的4日龄肉仔鸡随机分成5组,分别为对照组(基础日粮组)、发霉饲料组(即日粮中的正常玉米由发霉玉米替代)、试验组Ⅰ(发霉饲料+0.05%酵母β-葡聚糖)、试验组Ⅱ(发霉饲料+0.10%酵母β-葡聚糖)、试验组Ⅲ(发霉饲料+0.15%酵母β-葡聚糖),试验期为21d。结果表明:发霉玉米日粮中低剂量的霉菌毒素对肉仔鸡生长性能无影响,但可导致肝脏、心脏和脾脏肿胀,胸腺和法氏囊萎缩及血清中总蛋白、白蛋白、尿素氮浓度降低;在发霉玉米日粮中添加0.05%~0.15%的酵母葡聚糖,能降低发霉玉米中霉菌毒素对内脏器官的毒害作用,使器官指数和血清指标基本恢复到正常水平。更多还原

【Abstract】 The experiment was conducted to prepareβ-glucan by high pressure homogenization-enzyme-alkaline method from waste beer yeast and study the effects of yeastβ-glucan added in Mold-contaminated Feed on growth performance, organ and serum indices of broilers.The experiment included two parts: Exp.1 Preparation of Yeastβ-glucan by High pressure homogenization- Enzyme-Alkaline MethodTheβ-glucan was isolated by High pressure homogenization-Enzyme- Alkaline method from waste beer yeast. The relative preparation conditions were as follows: yeast liquid (its concentration as 15%) was treated by Highpressure homogenization. The precipitate obtained through centrifugation. 120 U/g(substrate) papain was added in the precipitate, then the mixture was treated isothermally at pH6.0 and 55℃with 6 h. The precipitate obtained through centrifugation again. 3%NaOH solution was added into the precipitate(solution:solids=2:1). The mixture was treated isothermally at 90℃with 2 h. After centrifuged,the precipitate was adjusted to pH7.0. The product was obtained through centrifugation and drying. The final yield and purity ofβ-glucan were 10.5% and 85.4%.Exp.2 Effects of Yeastβ-glucan Added in Mold-contaminated Feed on Growth Performance, Organ and Serum Indices of BroilersAn experiment was conducted to study the effects of yeastβ-glucan added in Mold-contaminated Feed on orowth performance, organ and serum indices of broilers. 180 broiler chicks(4-day-old)were randomly divided into 5 treatments:control(basal diet),Mold-contaminated feed (moldy corn added in basal diet),testⅠ(mold-contaminated feed+0.05%β-glucan), TestⅡ(mold-contaminated feed+0.05%β-glucan), testⅢ(mold- contaminated feed+0.05%β-glucan),and the experiment lasted for 21 days. The result showed that growth performance of broiler fed mold-contaminated feed was no difference; weights of liver, heart and spleen were significantly increased, and weights of thymus and bursa were reduced; the contents total protein,albumin and blood usea nitrogen in serum in serum were decreased. With 0.05%~0.15% yeastβ-glucan added in mold-contaminated feed, organ morphology and serum indices returned to normal levels.更多还原