【作者】 刘春龙；

【导师】 李杰；

【作者基本信息】 东北农业大学 ， 动物营养与饲料科学， 2004， 硕士

【摘要】 本研究由 ５ 个试验组成，选用 １２ 只雄性装有永久性瘘管的成年东北细毛羊，采用随机区组试验设计，分别饲喂 ４ 个水平（分别为 ０ｍｇ／㎏、１００ｍｇ／㎏、２００ｍｇ／㎏、３００ｍｇ／㎏）丝兰属植物提取物（YE）。研究了 ４ 个水平条件下 ＹＥ 对绵羊瘤胃发酵、对有机物质（ＯＭ）、干物质（ＤＭ）、中性洗涤纤维（ＮＤＦ）、酸性洗涤纤维（ＡＤＦ）瘤胃 ４８ｈ 降解率和消化率的变化以及对绵羊血液生化指标的影响。　 试验 １．　在上述添加水平下分别在试羊采食前及采食后的 ２、４、６、８ｈ 取瘤胃液样品进行分析，试验结果表明：各处理组与对照组 ｐＨ 值变化趋势相似，且均处于正常范围（ｐＨ５．５－７．５），在同一时间点相比 ｐＨ 值无显著差异（ｐ＞０．０５），但随时间的变化幅度有所不同，总体有随着 ＹＥ 添加水平的上升，ｐＨ 值总体变化幅度有变缓的趋势。　 同时，随着 ＹＥ 添加水平的增加，乙酸的浓度有降低的趋势，而丙酸的浓度则有上升的趋势，其中，３００ｍｇ／㎏组较对照组在饲喂后 ４ｈ 和 ６ｈ 乙酸浓度下降 １５．１％和 １９．８％，丙酸浓度则提高 ２２．７％和 ２２．９％，差异达显著水平（ｐ＜０．０５）。ＹＥ 的不同添加水平对丁酸、总挥发性脂肪酸浓度的变化并未产生明显影响。　 试验 ２．　分别于正试前一天及开始后第 ７、１４、２１、２８ 天取采食后 ２ｈ 瘤胃液，测定各种酶活及原虫数目，综合各组 ５ 次采样数据的平均结果表明：随着 ＹＥ 添加水平的升高，总脱氢酶活性有上升的趋势，但各组处理间差异不显著（ｐ＞０．０５）。纤维素酶活性随丝兰皂甙添加水平升高，表现出上升的趋势。其中 ３００ｍｇ／ｋｇ 组同对照组、１００ｍｇ／ｋｇ 组相比达显著水平（ｐ＜０．０５）；各处理组内部原虫数随天数的增加无明显规律性变化，但各处理组间有随着 ＹＥ 添加水平升高，原虫数表现出下降的趋势。３００ｍｇ／ｋｇ 组显著低于对照组和 １００ｍｇ／ｋｇ 组（ｐ＜０．０５）。　 试验 ３．　用尼龙袋法研究不同水平 ＹＥ 对全混合日粮有机物（ＯＭ）、干物质（ＤＭ）、中性洗涤纤维（ＮＤＦ）、酸性洗涤纤维（ＡＤＦ）瘤胃 ４８ｈ 降解率的影响。结果表明：各种饲粮养分的降解率均随 ＹＥ 添加水平的增加而呈上升趋势。其中，３００ｍｇ／ｋｇ 组 ＯＭ、ＤＭ、ＮＤＦ降解率显著高于对照组，而其他两水平组相对于对照组降解率差异不显著（ｐ＞０．０５）。各处理间对 ＡＤＦ４８ｈ 降解率的影响虽有上升趋势，但 ４ 组间差异不显著（ｐ＞０．０５）。　　 试验 ４．　不同水平 ＹＥ 对全混合日粮（ＴＭＲ）中 ＡＤＦ 消化率虽有上升趋势，但各处理组间差异不显著（ｐ＞０．０５）。ＯＭ、ＤＭ、ＮＤＦ 消化率随着 ＹＥ 添加水平的增加而呈上升趋势，其中 ３００ｍｇ／ｋｇ 组显著高于对照组（ｐ＜０．０５）。　 试验 ５．　各组于正试期开始后每隔 ７ 天采血一次，共采集 ４ 次，测定各组试羊血液生化指标，结果表明：各组间各种指标差异不显著（ｐ＞０．０５），均处于绵羊正常生理范围内，血清尿素氮有降低的趋势，对绵羊血液其他生化指标（血清谷草转氨酶、谷氨酰转肽酶、碱性磷酸酶、乳酸脱氢酶、肌酐）无明显规律性影响。更多还原

【Abstract】 Twelve male adult sheep with permanent rumen cannula were used in a single factorrandomized block design to study the effect of four levels of YE (0mg/㎏、100mg/㎏、200mg/㎏、300mg/㎏) on rumen fermentation items（pH，VFAconcentration，enzymes activity andthe number of protozos），rumen digestibilities (48h) and apperent digestibilities of OM，DM，ADF，NDF，blood biochemical items. Trial 1. Rumen liquid was sampled at 0h，2h，4h，6h and 8h after feeding. pH，VFAconcentration were mensurated.The results showed that pH were not distinctly influenced forfour groups at the same time points. The pH of all levels were in normal range(pH5.5-7.5).The variety trends of pH have delayed as the concentration of YE supplementincreasing. With the increaing of YE level，the concetration of acetic decreased accordingly，but thepropionic concetration increased.YE at level of 300mg/kg, compared with control ,the aceticconcentration decreased by 15.1% and 19.8% at 4h and 6h after feeding, respectively.Thediffereces of concentratins of YE did not significantly influenced the concentration of totalvolatile fatty acids(TVFA). Trial 2. Enzymes activity and number of protozos of ruminal liquid were measured at 2hafter feeding at every seven days during the twenty-eight days. According to the results of thisfive days, the changing trends of activities of Total dehydrogenase and Cellulase wereincreased as the level of Yucca asponins increasing. Cellulase activity was distinctlyinfluenced at level of 300mg/kg compared with control and 100mg/kg group .The the numberof protozos in every group has no distinct regulation，but there were decreasing trends as theYE level increasing. The number of protozos of 300mg/kg YE was distinctly influencedcompared with control and 100mg/kg group. Trial 3. The effect of the three levels of YE on the rumen degradability of DM，OM，NDFand ADF in 48h were evaluated with nylon bags. The results showed that the trends ofdegradability of nutrient material increased as YE supplement incresing. Rumen II<WP=10>Abstractdegradability of OM、DM、NDF in 48h for 300mg/kg YE was distinctly influenced comparedwith control and 100mg/kg group (P<0.05) ，but the rumen degradabilities of ADF in 48h infour groups were not distinctly influenced. Trial 4 . In this experiment the effect of three levels of YE on the apparent digestibility ofADF were studied.The results showed that four groups were not distinctly influenced bysupplement of YE（p>0.05）. Apparent digestibilities of DM，OM，NDF had decreasing trendsas the increasing of YE.Apparent digestibilities of DM，OM，NDF for 300mg/kg YE weredistinctly influenced compared with control group (P<0.05). Trial 5. The results showed that the blood biochemical items of four groups were notdistinctly influenced by YE supplement（p＞0.05）. All blood biochemical items were innormal range.The concentration of urea-N in serum decreased as the the increasing of YE.Theactivities of AST、GGT、ALP、LDH、CRE were not distinctly influenced. Candidate：Liu Chunlong Specialty：Animal nutrition and feed science Supervisor:：Prof. Li Jie更多还原