【作者】 唐维新；

【导师】 周禾；

【作者基本信息】 中国农业大学 ， 草业科学， 2004， 硕士

【摘要】 试验以紫花苜蓿为材料研究绿汁发酵液(PFJ)发酵原理和不同浓度绿汁发酵液对紫花苜蓿青贮品质的影响，两部分试验均采用随机区组设计。在绿汁发酵液(PFJ)发酵原理的研究中，在苜蓿汁液中添加不同浓度的葡萄糖(添加量分别为5g／100ml、2g／100ml、0.5g／100ml)，在发酵的不同时间(分别为0h、24h、48h和72h)对乳酸菌、大肠杆菌的生长情况和发酵过程pH值变化情况进行观察测定。结果表明，添加葡萄糖的发酵液pH值能够迅速下降、乳酸菌数量呈指数递增、大肠杆菌迅速被抑制，其效果明显好于对照组，而且葡萄糖添加量越高效果越好；添加葡萄糖的各处理均在发酵48h时乳酸菌数量达到最高、大肠杆菌数量每毫升小于100cfu。为避免不必要的浪费和确保青贮试验成功，我们采用2g／100ml葡萄糖添加组作为紫花苜蓿青贮试验的添加剂。 在研究紫花苜蓿青贮品质的试验中，采用第3茬初花期紫花苜蓿鲜草(DM为19.89％)和晾晒8h的苜蓿(DM为28.98％)作为原材料，用青贮粉碎机轧成2～4cm小段后均匀喷洒不同用量的绿汁发酵液(20ml／kg、2ml／kg、0.2ml／kg)。结果表明，喷洒绿汁发酵液的处理组青贮效果明显好于对照组，显著降低青贮pH值、氨态氮、乙酸和丁酸含量，提高乳酸含量，但对青贮可溶性糖和粗蛋白含量无太大影响。添加量越高青贮品质改善效果越明显，以PFJ20ml／kg和2ml／kg处理组青贮品质为最优。更多还原

【Abstract】 Two laboratory scale experiments have been made using alfalfa . In experimen 1 , the effects of different fermented time (Oh ,24h ,48h ,72h) and adding glucose at rate of 50gL-1 20gL-1 5gL-1 on Previously Fermented Juice (PFJ) quality were studied ; In experiment 2, the Influences of treatments of alfalfa with different PFJ content (20mlkg-1,2 mlkg-1,0.2 mlkg-1) on silage quality at two dry matter levels (35.89% ,45.98%) were also studied . All the treatments consisted of three replications.In the 1st experiment, the PFJ was prepared by macerating 2.3kg of freshly alfalfa with 6.4L of water using a blender and filtered through double cheese cloth .The filtrate was kept anaerobically at 30℃ with or without glucose . The addition of glucose was effective in increasing amounts of lactic acid bacteria (LAB) , depressing the growth of coliform bacteria rapidly and lowering the pH value of PFJ , but the PFJ without glucose resulted in poor fermented quality . The PFJ quality was affected by both fermented time and glucose content, and got better with increasing glucose content, the largest and the least amounts of LAB and coliform bacteria of all the treatments were found on 48h after fermented . But we think the PFJ treated with glucose at rate of 20gL-1 was most suitable for additive of alfalfa silage.In the 2nd experiment ,It was carried out using third growth of alfalfa harvested just before the flowering stage, the harvested alfalfa was cut with a disintegrator into 2~4cm after wilted 0 ,8 hours, and treated before ensiling with 20ml ,2ml and 0.2mlkg-1 PFJ or 20mlkg-1water, they were preserved for 48 days . Results from this experiment showed the addition of PFJ was effective in improving the silage quality by increasing lactic acid content, depressing the formations of actic acid and ammonia , and lowering the pH value for both dry matter levels . The silage quality got better with increasing PFJ content, but the treatments with water at every moisture content were in poor quality and a large amount of butyric acid was found . The treatments with 20mIkg-1,2 mlkg-1 PFJ showed a relatively good quality.更多还原