不同氮源饲粮添加低水平缩合单宁对体外发酵的影响

发布时间：2018-10-20 12:43

【摘要】：本实验分别以豆粕和苜蓿干草为氮源饲粮,以此做底物添加低水平缩合单宁,进行体外发酵试验,研究不同氮源饲粮添加低水平缩合单宁对瘤胃体外发酵参数的影响,为缩合单宁在保护过瘤胃蛋白的进一步应用上提供科学依据。体外培养试验：研究不同氮源饲粮添加低水平缩合单宁对瘤胃体外发酵参数的影响。底物分别为豆粕饲粮和苜蓿干草饲粮各2g,分别添加0.3%、0.6%、0.9%的低水平缩合单宁,标记为豆粕组对照组(0%)、豆粕组D1(0.3%)、豆粕组D2(0.6%)、豆粕组D3(0.9%)和苜蓿干草组对照组(0%)、苜蓿干草组M1(0.3%)、苜蓿干草组M2(0.6%)、苜蓿干草组M3(0.9%)。体外培养24h后测定各处理组的pH值、产气量、氨态氮、菌体蛋白、挥发性脂肪酸。结果表明：在豆粕饲粮和苜蓿干草饲粮中添加低水平缩合单宁,随着缩合单宁含量的增加和发酵时间的延长,pH值呈下降趋势。豆粕组在6h时,D2组和D3组显著低于D1组。在苜蓿干草中添加不同量低水平缩合单宁时,各个采样时间点组内差异均不显著。产气量在整个过程中差异显著,随着缩合单宁添加量的增多而下降,豆粕组产气量高于苜蓿干草组的产气量,豆粕和苜蓿干草中添在加0.9%的低水平缩合单宁时产气量最低,低水平缩合单宁有降低产气量的作用。添加低水平缩合单宁在豆粕饲粮和苜蓿干草饲粮中,随着时间的延长,氨态氮的含量呈增加的趋势,缩合单宁添加量的增加,氨态氮含量的增长速度降低,在24h时增长速度有回升的趋势。苜蓿干草饲粮和豆粕饲粮中添加低水平缩合单宁,D1组、D3组和M1组、M3组的菌体蛋白含量呈先上升后下降的趋势,D2组和M2组的菌体蛋白含量呈下降趋势。总的挥发性脂肪酸和乙酸含量最低的是M3.组,其次是M2组和M1组,在体外发酵的整个过程中,均显著低于豆粕的三个处理组,但随着时间的延长,差异逐渐减少。两种氮源饲料中丙酸的产量最高的组分别是D3组和M3组。不同氮源饲粮中低水平缩合单宁的添加量的大小,对瘤胃发酵参数有一定的影响。随着低水平缩合单宁添加量的增多,pH值下降缓慢,产气量显著降低,氨态氮的含量呈缓慢上升的趋势,菌体蛋白的含量以及总挥发性脂肪酸和乙酸的含量均呈下降的趋势,丙酸的含量随着低水平缩合单宁添加量的增多而增加。与豆粕相比,苜蓿干草中添加低水平缩合单宁后各类挥发性脂肪酸是较低的,且挥发性脂肪酸维持在一个稳定的状态,低水平缩合单宁的添加量对挥发性脂肪酸的影响较小。
[Abstract]:In this experiment, soybean meal and alfalfa hay were used as substrate to add low level condensed tannin, and in vitro fermentation experiment was carried out to study the effect of low level condensed tannin on rumen fermentation parameters. It provides scientific basis for further application of condensed tannin in protecting rumen protein. In vitro culture experiment: the effect of low level condensed tannin on rumen fermentation parameters was studied. The substrate was soybean meal diet and alfalfa forage diet of 2 g, respectively, adding 0.3% 0. 6% of low level condensed tannin, and 2 g of alfalfa hay diet, respectively. It was labeled as soybean meal group (0%), soybean meal group D1 (0.3%), soybean meal group D2 (0.6%), soybean meal group D3 (0.9%) and alfalfa hay group (0%), alfalfa hay group M1 (0.3%), alfalfa hay group M2 (0.6%), alfalfa hay group M3 (0.9%). The pH value, gas production, ammonia nitrogen, bacterial protein and volatile fatty acids were measured after 24 hours of culture in vitro. The results showed that the pH value of soybean meal and alfalfa hay diet decreased with the increase of condensate tannin content and fermentation time. Group D 2 and group D 3 were significantly lower than group D 1 at 6 h after soybean meal treatment. When different amounts of condensed tannins were added to alfalfa hay, there was no significant difference among different sampling time points. The gas production of soybean meal group was higher than that of alfalfa hay group, and the gas production of soybean meal and alfalfa hay was the lowest when adding 0.9% of low level condensed tannin. Low level condensed tannin can reduce gas production. Adding low level condensed tannin into soybean meal diet and alfalfa hay diet, the content of ammonia nitrogen increased with the increase of time, and the increasing rate of ammonia nitrogen content decreased with the increase of condensed tannin content. In 24 hours, the growth rate has a trend of recovery. The bacterial protein content in alfalfa hay diet and soybean meal diet increased at first and then decreased in D1 group, D3 group and M1 group, but decreased in D2 group and M2 group. The content of total volatile fatty acids and acetic acid was the lowest in M3. Group M2 and group M1 were significantly lower than the three groups of soybean meal in the whole process of in vitro fermentation, but the difference gradually decreased with the prolongation of time. The highest yield of propionic acid in two kinds of nitrogen feed was D 3 and M 3, respectively. The addition of low level condensed tannin in different nitrogen sources had a certain effect on rumen fermentation parameters. With the increase of the amount of condensed tannin at low level, the pH value decreased slowly, the gas production decreased significantly, the content of ammonia nitrogen increased slowly, the content of bacterial protein, the contents of total volatile fatty acids and acetic acid decreased. The content of propionic acid increased with the increase of low level condensed tannin. Compared with soybean meal, all kinds of volatile fatty acids in alfalfa hay were lower after adding low level condensed tannins, and the volatile fatty acids remained in a stable state, and the effect of low level condensed tannin on volatile fatty acids was less.
【学位授予单位】：延边大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S816.7

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