节点文献

不同浓度绿汁发酵液和脱氢乙酸钠对青贮水稻秸品质和有氧稳定性的影响

The Effects of Different Concentrations of Previosly Fernmented Juice and Dehydroaceticacid on the Quality and Aerobic Stability of Rice Straw Silage

【作者】 刘丹丹

【导师】 张永根;

【作者基本信息】 东北农业大学 , 动物营养与饲料科学, 2008, 硕士

【摘要】 黑龙江省是奶业发展的优势区域,但是,粗饲料不足尤其是优质粗饲料的缺乏已经成为奶牛业发展的限制因素,探索新的青贮饲料来源具有重要意义。黑龙江省有着丰富的水稻秸资源,而用于反刍动物的水稻秸比例还不足15%,其余多被焚烧。随着水稻收获工艺的改进,尤其是蒋亦元院士发明的割前脱粒技术在全省的应用,使得水稻秸的养分含量具备了青贮的条件。水稻青贮秸技术在日本已经取得成功并在广泛应用,但在国内关于这项实用技术的研究较少,尤其是采用绿汁发酵液青贮水稻秸,在国际上还是属于先例。由此可见,本研究进行的水稻秸青贮技术的探索,首次采用机械割前脱粒后的水稻秸,采用两种新型添加剂(绿汁发酵液和脱氢乙酸钠)进行青贮,不仅可以解决粗饲料不足的问题,还可以有效地改善由于焚烧或者处理不当而造成的环境污染。试验共分为两部分。试验一为选用水稻秸为青贮原料,利用商品乳酸菌制剂(LAB)和紫花苜蓿配置的不同浓度绿汁发酵液进行喷洒后袋贮,绿汁发酵液共分为4个浓度,其中浓度一:紫花苜蓿20g添加250ml无菌水,搅拌过滤,30℃厌氧发酵2d制得,称其为PFJ;浓度二:紫花苜蓿20g添加250ml无菌水,搅拌过滤,稀释20倍后30℃厌氧发酵2d制得,称其为dPFJ;浓度三:将发酵得到的PFJ液体稀释20倍制得,称其为PFJ20;浓度四:将发酵得到的dPFJ液体稀释20倍制得,称其为dPFJ20。每组设16个重复,共制作青贮袋96个。试验二同样选用水稻秸为青贮原料,采用不同浓度的脱氢乙酸钠进行喷洒袋贮,脱氢乙酸钠的添加量为三个浓度:0.05%、0.1%和0.2%。两个试验均采用袋贮的处理方法,每袋填装4kg,用真空泵抽真空后封口,至于阴凉处,同时以空白作为对照组。每组设16个重复,共制作青贮袋48个。在青贮过程中及青贮发酵完成后通过测定pH值、VBN/TN、CP、NDF、ADF和挥发性脂肪酸等指标,对各处理组的青贮水稻秸进行感观和发酵品质的评定,及有氧稳定性跟踪试验,综合考虑发酵效果、营养价值等指标,以及经济成本等方面因素,采用单因素方差分析方法,选出青贮质量最好的绿汁发酵液处理组和抑制二次发酵效果最好的脱氢乙酸钠浓度。试验结果表明:1.添加绿汁发酵液的处理组中,PFJ20在稻秸发酵过程中pH值一直比较稳定,没有大的波动且数值为所有处理组中最低,与其他各组差异显著(P<0.01)。PFJ组和dPFJ20组效果稍差但仍然好于其它各组合,NH3-N含量在发酵过程中均为递增趋势。发酵完成后,按照青贮质量评分,PFJ20组处理的青贮水稻秸,在感官评价上优于其它组合;在有机酸和营养物质评定中, PFJ20组的乳酸含量较对照组增加了104.2%,乳酸/乙酸值为7.2,其次为PFJ组。2.在添加脱氢乙酸钠试验中,添加浓度为0.2%处理组的pH值为4.18,与对照组、添加量为0.05%组、添加量为0.1%组差异均显著(P<0.01);乳酸含量中,添加量为0.1%和0.2%组分别为2.30%和2.35%,乳酸/乙酸值为5.75和5.88,二者差异不显著(P>0.05)。3.在有氧稳定性试验中,添加脱氢乙酸钠浓度0.1%组和添加0.2%组效果均十分明显,第一次升温便比对照组和添加量为0.05%组推迟了一天,第二次升温更是推迟了两天,对抑制二次发酵具有显著效应。从本实验结果可以看出:在青贮水稻秸中使用发酵促进剂或者添加脱氢乙酸钠,都会较大程度的保存养分,改善发酵品质,抑制二次发酵,显著提高青贮饲料的品质;对各处理组青贮水稻秸效果进行综合评价,可以得到以下结论:1)在青贮水稻秸中绿汁发酵液与乳酸菌制剂(LAB)相比,PFJ20组效果最优,能显著改善青贮品质,其次为PFJ组和dPFJ组,而考虑经济成本问题,在PFJ组和dPFJ组这两组中,应选择后者。2)向青贮原料中添加不同浓度的脱氢乙酸钠(0.05%、0.1%、0.2%),对发酵品质均有改善,但差异不显著(P﹤0.05),其中添加0.1%组和0.2%组效果较好。3)添加0.1%和0.2%浓度的脱氢乙酸钠可提高开窖后青贮水稻秸的有氧稳定性。在同等发酵品质下,添加0.1%浓度的脱氢乙酸钠在经济上更可行。

【Abstract】 Heilongjiang province is a predominance-area of milk industry development. But the shortage of coarse fodders, in particular the ck of high quality coarse fodders, has become to a restrictive factor for milk industry development. Therefore, it has very important meaning to explore the source of new silages. Heilongjiang province has abundant resource of rice straw, but the percent of rice straw for ruminant feeding is less than 15% and the rest are burnt. With rice harvest technology improvement, especially“the threshing before mowing”charged by Academician Jiang Yiyuan was widely used in whole province, the water content of rice straw can meet the qualification for silage. The technology of rice straw silage has obtained great success and widely applied in Japan, however the practical technology is seldom studied in China. Thus it can be seen that the study of rice straw silage technology is not only to resolve the shortage of coarse fodders, but also to effectively improve environmental pollution due to burning or inappropriate processing.Previous Fermented Juice (PFJ) and Lactic Acid Bacteria (LAB) are belongs to promoting silage additives. PFJ is a kind of new silage additive these years and LAB is a silage additive that commonly used in production. Dehydroacetate Acid (DHA), a fermentation-inhibiting additive, is mainly used in food at present and seldom reported for the application of silage. Three additives were used for silage rice straw in this test. Different concentrations of DHA were mixed with PFJ, PFJ20 and LAB and sprinkled to the rice straw, then sealed silage and compared with the blank control group. The best effect of additive combination treated on silage rice straw was selected by comprehensive consideration of these indexes such as fermentation effect and nutritional value etc. in the process of silage and after ensiling in terms of sensory characteristics and fermentation quality.The test showed that the PH value of the combination of PFJ20nd PFJ was always relative sTab., no drastic fluctuations and the numerical value was the lowest in all treatment combination. The secondary was the treatment combination of PFJ and PFJ20The effect of LABcombination is better than others combination. The content of NH3-N was increasing tendency in the process of fermentation, but the growing tendency was slowed down while increasing the content of DHA. However the influence was remarkable for the PFJ20 and LAB combination and no significant relieved to PFJ group. According to the silage quality to grade after ensiling, the sensory characteristics of silage rice straw which treated by PFJ20、PFJ、dPFJcombination were better than other groups. The group of PFJ and PFJ20was the best in organic acid estimation, in comparison of CP content. The PFJ group and high concentration DHA group have low value of NDF and ADF.The results indicated that the fermentation accelerators (PFJ, PFJ20 and LAB) and DHA in silage rice straw can save nutrient and improve fermentation quality, restrain secondary fermentation, and enhance the silage quality observably. The good silage result can be obtained by adding only high concentration PFJ without the DHA. Indeed, the result would be better while adding the DHA. The result were also better when the low concentration PFJ20 and LAB cooperated with the DHA (0.1%、0.2%).

节点文献中: