【作者】 王红梅；

【导师】 孙启忠；

【作者基本信息】 中国农业科学院 ， 草业科学， 2013， 博士

【摘要】 为了解呼伦贝尔草原牧草青贮特性，于2010～2011年先后在呼伦贝尔市的海拉尔、牙克石、根河、额尔古纳、满洲里、陈巴尔虎旗、新巴尔虎右旗、新巴尔虎左旗和鄂温克自治旗等9个地方，共采集了32个站点（群落）牧草材料，包含19科98种牧草。以不同植物群落牧草为材料，进行了青贮微生物、营养成分及发酵品质等方面的研究，主要结论如下：1、青贮原料及青贮体系中微生物的种类、数量均存在较大差异。青贮原料上附生的乳酸菌数量（10~2～10~7cfu/g FM）远远少于有害微生物数量。不同青贮原料间各类微生物数量变异程度大小顺序为乳酸菌＞大肠杆菌＞好氧细菌＞酵母与霉菌。青贮饲料中乳酸菌数量为10~4～10~8cfu/gFM，大肠杆菌只存在于8个群落牧草青贮中。2、从青贮原料及青贮饲料中共分离出133株乳酸菌，分别属于8个属的植物乳杆菌、类植物乳杆菌、短乳杆菌、旧金山乳杆菌、L.saniviri、干酪乳杆菌、草乳杆菌、绿色魏斯氏菌、融合魏斯氏菌、赫伦魏斯氏菌、印度微小杆菌、广布肉杆菌、戊糖片球菌、乳酸片球菌、柠檬明串珠菌、肠膜明串珠菌肠膜亚种、乳酸乳球菌乳酸亚种、乳酸乳球菌、硫黄肠球菌、粪肠球菌、白蚁肠球菌、摩拉维亚肠球菌、鹑鸡肠球菌、淡黄肠球菌、蒙氏肠球菌、希氏肠球菌、耐久肠球菌和屎肠球菌等28个菌种，其中，植物乳杆菌、短乳杆菌、戊糖片球菌、乳酸片球菌和粪肠球菌的比例较大。另外，菌株DMB23和DME65属于乳杆菌属，DMA37属于乳球菌属，但此3株乳酸菌未能鉴定到种水平。3、筛选出8株产酸速率较快的乳酸菌；DMC80、DMG5、DMB25、DMB28、DMH20、DMA22、DMF14和DME14。其中，菌株DMC80、DMG5和DMH20的产酸速率和生长速度较快。4、牧草含水量为60～73%时，青贮营养品质较好。青贮后牧草干物质损失率为7.94～15.44%，可溶性碳水化合物分解率为41.65～64.20%。5、32份青贮饲料感官评定得分为41～78分，可划分出3个等级：优等（2份），一般（3份），良好（27份）；有机酸含量评定得分为16～100分，将青贮质量划分为4个等级：很好（16份），好（8份），合格（7份），失败（1份）。青贮有机酸含量得分越高，其pH值表现越低；氨态氮含量评定得分为13～50分，可划分为4个等级：优（11份）、良好（13份）、一般（6份）、可（2份）；pH值与乙酸、丁酸和氨态氮含量呈极显著正相关，乳酸含量与氨态氮含量呈极显著负相关，WSC含量与CP含量呈极显著负相关（P＜0.01），乙酸与氨态氮含量呈显著正相关（P＜0.05）。6、不同群落牧草青贮营养品质综合评价所得结论与有机酸含量评定结果基本一致，以羊草为主的群落（第22号）牧草青贮营养品质较好，而为以山野豌豆为主的群落（第3号）牧草青贮营养品质相对较差。以禾草为主的群落牧草青贮成功率为94%以上，以豆科牧草为主的群落牧草青贮成功率为90%。更多还原

【Abstract】 To learn the silage features of hulunbuir prairie grass, a total of32forage materials were collected from9places (Hailaer, Yakeshi, Genhe, Eerguna, Manzhouli, Old Barag Banner, New Barag Right Banner,New Barag Left Banner and Ewenkezizhiqi), including19families and98species. The different plantcommunities grass in hulunbuir prairie were chosen to determine the characteristics of silagemicroorganisms and fermentation quality, and main conclusions are as follows:1. The number and species of microorganism on the raw materials and in silage varied intensely.Counts (10~2～10~7cfu/g FM) of adnascent lactic acid bacteria on silage materials were too much lessthan that of harmful microorganisms. The descending order of variation of microorganism countsamong different silage materials was lactic acid bacteria, coliform bacteria, aerobic bacteria, yeast andmold. The number of lactic acid bacteria was from10~4to10~8cfu/g FM, but coliform bacteria wasdetected only in eight silages..2. One hundred and thirty-three lactic acid bacteria strains were isolated from silage materials andsilage. These strains belonged to twenty-eight species of eight genuses, including L. plantarum, L.paraplantarum, L. brevis, L. sanfranciscensis, L. saniviri, L. casei, L. graminis, W. viridescens, W.confusa, W. hellenica, Exiguobacterium indicum, Carnobacterium divergens, P. pentosaceus, P.acidilactici, Le. citreum, Le. mesenteroides subsp. mesenteroides, L. lactis subsp. lactis, L. lactis, E.sulfurous, E. faecalis, E. termites, E. moraviensis, E. gallinarum, E. pallens, E. mundtii, Enterococcushirae, E. durans and E. faecium, and number of L. plantarum, L. brevis, P. pentosaceus, P. Acidilacticiand E. faecalis was significant. In addition, strains DMB23and DME65belonged to Lactobacillus, thestrain DMA37belonged to Lactococcus, but these three lactic acid bacteria were not identified tospecies level.3. Eight lactic acid bacteria strains DMC80、DMG5、DMB25、DMB28、DMH20、DMA22、DMF14and DME14were screened for their quicker acid-production rate, and L. plantarum DMC80, L.paraplantarum DMG5and L.saniviri DMH20had more quicker acid-production rate and growthspeed than other strains.4. The silage nutrient quality can be better when its moisture content was from65%to70%. Afterensilage, the dry matter loss rate was from7.94%to15.44%, and the decomposition rate of watersoluble carbohydrates was from41.65%to64.20%.5. The sensory evaluation score of silage was from41to78points, and can be divided into threelevels: excellent (including two materials), good (including twenty-seven materials) and moderate(including three materials). The score of organic acid content was from16to100points, and the silagequality was divided into four grades: high(including sixteen materials), good (including eight materials),qualified(including seven materials) and failed(including only one material). The higher score oforganic acid content in silage was, the lower pH value was. The evaluation score of ammonia nitrogencontent was from13to50points, and can be divided into four grades: high (including eleven materials),good (including thirteen materials), general (including six materials) and passably (including two materials). The pH value showed a highly significant positive correlation with acetic acid, butyric acid,and ammonia nitrogen content (P＜0.01). There was a highly significant negative correlation betweenlactic acid content and ammonia nitrogen content, so was water soluble carbohydrates content and crudeprotein content (P＜0.01). There was a significant positive correlation between acetic acid and ammonianitrogen content(P＜0.05).6. The results of comprehensive evaluation about nutritional quality of silage from different grasscommunities were similar to the evaluation of organic acid content. The nutritional quality was better ingrass silage of L. chinensis dominated communities (No.22), with higher lactic acid content and lowerpH value, no butyric acid and higher WSC contents. But the nutritional quality was relatively poor ingrass silage of Vicia amoena dominated communities (No.3). More than94%of grass silage fromgramineae herbage dominated communities can be successful, and90%of grass silage from leguminousherbage dominated communities can succeed.更多还原