【作者】 柳英；

【导师】 陈喜斌； 彭健；

【作者基本信息】 华中农业大学 ， 动物营养与饲料科学， 2005， 硕士

【摘要】 本研究以双低菜籽皮的中性洗涤纤维（Neutral Detergent Fiber,NDF）含量为评定指标。采用混合嵌套设计从干式NaOH法（处理时间分别为1d、2d、3d）、尿素氨化法（处理时间分别为10d、15d、20d）、碱化-氨化复合处理（处理时间分别为15d、20d、25d）筛选出最佳处理组及其处理时间;采用L₉（3⁴）正交设计筛选出最佳配比的纤维素酶、β-聚糖酶、木聚糖酶和a-淀粉酶处理组;从而得到最佳化学处理组和最佳复合酶制剂处理组。采用扫描电子显微镜（Scanning Electron Microscope,SEM）技术分析上述最佳处理组处理的双低菜籽皮的结构;并分别以稻草、未处理双低菜籽皮、经最佳化学组处理的双低菜籽皮、经最佳复合酶制剂组处理的双低菜籽皮为粗料配制不同日粮,研究其对湖北麻城黑山羊的生长性能的影响。试验结果如下: 与对照组（未处理组）相比,双低菜籽皮经干式NaOH法、尿素氨化法、碱化-氨化复合法处理后中性洗涤纤维（NDF）含量降低,中性洗涤纤维24h降解率升高。双低菜籽皮经不同化学方法处理后,中性洗涤纤维（NDF）含量组间差异极显著（P<0.01）,中性洗涤纤维24h降解率组间差异极显著（P<0.01）;双低菜籽皮经同种方法不同时间处理后,时间对NDF含量及中性洗涤纤维24h降解率的影响是极显著（P<0.01）。就中性洗涤纤维24h降解率而言,干式NaOH处理组比对照组的分别提高了74.22%、66.16%、58.64%,尿素氨化处理组比对照组的分别提高了63.81%、19.07%、15.64%,碱化-氨化复合处理组比对照组的分别提高了28.88%、58.04%、7.79%。 双低菜籽皮经不同配比的复合酶制剂处理后NDF含量组间差异不显著（P>0.05）,中性洗涤纤维24h降解率组间差异不显著（P>0.05）。与对照组相比,NDF含量均下降,分别降低了8.15%、6.59%、8.56%、9.81%、8.42%、9.57%、7.11%、7.62%、8.05%;中性洗涤纤维24h降解率均有所提高,分别提高了88.07%、89.05%、72.75%、61.42%、59.29%、54.77%、68.72%、64.96%、90.74%。 扫描电镜观察发现处理前后双低菜籽皮的物理结构变化显著。未处理的双低菜籽皮结构紧密,细胞器清晰可见;经过碱化-氨化复合处理之后,薄壁组织膨胀,形成一些“孔穴”结构,并且大部分的细胞器解体脱落;经过复合酶制剂处理后双低菜籽皮表面光滑,“孔穴”结构更加规则,并且细胞器基本完全解体脱落。表明双低菜籽皮经过处理后细胞壁疏松,为瘤胃液的渗透提供有利的条件,从而提高双低更多还原

【Abstract】 The content of neutral detergent fiber （NDF） in double-low rapeseed hull was assessed as deliberated index. In the experiments, the mixed nesting design was adopted to screen out the optimal treatment group and treatment time by three different chemical methods: dry NaOH method （the treated time spans were 1d, 2d, 3d, respectively） ; urea-ammonification treatment （the treated time spans were 10d, 15d, 20d, respectively）; alkali-ammonification treatment（the treated time spans were 15d, 20d, 25d, respectively）. L₉ （3⁴） orthogonal design was adopted to screen out the optimal treatment group, which was characterized by the optimal ratio of cellulose, β-glucanase, xylanase and a-amylase. Thus, the optimal chemical treatment and optimal enzyme preparation treatment were determined. Structure changes of optimal methods were analysed with scanning electron microscope （SEM）. Meanwhile, the experiments studied the effects of the different diets, which were formulated with straw, untreated double-low rapeseed hull, double-low rapeseed hull treated with chemical method and double-low rapeseed hull treated with enzyme preparation as the roughages, respectively, on the growth performance of black goats from Hubei Macheng. The results were as follows:Compared with the control group （untreated group） , the contents of NDF in double-low rapeseed hull treated by dry NaOH method, urea-ammonification treatment and alkali-ammonification treatment all decreased; and the content of the degradability of NDF after 24h in rumen was enhanced. After the hull had been treated by different chemical methods, there was extremely significant difference in the content of NDF and in the degradability of NDF （P<0.01） . After the hull had been treated for different time spans by the same method, there was extremely significant difference in the content of NDF and in the degradability of NDF within the groups （P<0.01） . Compared with thecontrol, the degradability of NDF of double-low rapeseed hull treated by dry NaOH method increased by 74.22%, 66.16%, 58.64%, respectively; the degradability of NDF in the hull treated by urea-ammonification treatment increased by 63.81%, 19.07%, 15.64%, respectively; the degradability of NDF in the hull treated by alkali-ammonification treatment increased by 28.88%, 58.04%, 7.79%, respectively.There was no significant difference in the content of NDF or in the degradability of NDF between trial groups after double-low rapeseed hull had been treated by enzyme preparation （P>0.05）. Compared with the control, the content of NDF of treated groups decreased by 8.15%, 6.59%, 8.56%, 9.81%, 8.42%, 9.57%, 7.11%, 7.62%, and 8.05%, respectively; the degradability of NDF of treated hull increased by 88.07%, 89.05%, 72.75%, 61.42%, 59.29%, 54.77%, 68.72%, 64.96%, and 90.74%, respectively.SEM experiment showed that the structure of the pre-and post-treated double-low rapeseed hull changed significantly. The structure of untreated double-low rapeseed hull was compact, and the cellular organelles were easily invisible. After alkali-ammonification treatment, the thin cell tissue expanded, and some "aperture" structures formed. Most cellular organelles disintegrated and dropped. The surface of double-low rapeseed hull treated by enzyme preparation was smooth. The "aperture" structures were more regular, and the cellular organelles disintegrated and dropped completely. This experiment showed that the cell wall became loose after the double-low rapeseed hull had been treated, which provided advantaged conditions for infiltration of rumen liquid, thus enhancing the efficiency of double-low rapeseed hull utilization.There was significant difference in feed intake, average daily gain （ADG） and Feed/Gain （F/G） of goats between the two treated group and the straw group （P< 0.05） . There was not significance in these aspects between the trial group and the untreated double-low rapeseed hull group （P>0.05 ）; however, the feed intake and ADG of the goats increased, while F/G of the goats decreased.The above results suggested that the method of alkali-ammonification treatment for 20 days at normal temperature was optimal; the optimal ratio of enzyme preparation was cellulose, 0.3846g; fi-glucanase, 0.1667g; xylanase, 0.2000g; a-amylase, 0.0125g （500g double-low rapeseed） . Alkali-ammonification treatment and enzyme preparation treatment could enhance the nutritive value of double-low rapeseed hull, and the treateddouble-low rapeseed hull could promote the growth performance of goats.更多还原