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本文综述了反刍动物瘤胃甲烷(CH4)产生的基本过程、瘤胃CH4产量预测模型的类型及特点,分析了现有模型存在的问题,指出了研究瘤胃CH4产量预测模型的重要性. 相似文献
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《中国畜牧兽医文摘》2015,(7)
甲烷是仅次于CO2的全球第二大温室气体,其中,反刍动物年产CH4约7.7×107吨,占大气中的CH4总量的25%,而且每年还以1%的速度递增。因此研究反刍动物瘤胃甲烷的营养调控对甲烷的生成影响有重要意义。本文综述了瘤胃甲烷的产生机制、瘤胃产甲烷菌与瘤胃微生物的关系和反刍动物瘤胃甲烷的营养调控措施。 相似文献
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反刍动物瘤胃内甲烷产生及其调控 总被引:4,自引:0,他引:4
反刍动物瘤胃内甲烷产生及其调控韩继福解放军农牧大学(130062)甲烷主要是由数种甲烷菌通过CO2和H2进行还原反应产生的,化学性质极稳定,一旦生成后很难被代谢(至少在瘤胃内)。它是以暧气的方式经口排出体外的。研究发现,反刍动物每天产生的甲烷能占饲料... 相似文献
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瘤胃微生物蛋白质产量的调控 总被引:2,自引:0,他引:2
反刍家畜瘤胃内栖居着大量微生物 ,其厌氧发酵合成的微生物蛋白可以为动物提供蛋白质需要量的 40 %~ 60 % (Church,1988)。小肠可利用的蛋白主要来自于微生物蛋白 (Orskov and Fraser,19 73) ,因此了解影响瘤胃微生物产量的调控因素对于研究反刍动物的营养调控技术有重要的意义。1 营养调控能量、蛋白质、进食水平、青贮饲料等都是影响瘤胃微生物蛋白质产量的营养因素 (韩兴泰 ,1993;袁森泉 ,1998;陈友慷 ,1991)。目前的研究主要集中于肽、氨基酸、维生素、微量元素、矿物质等方面。1.1 维生素反刍动物自身可以合成 B族维生素 ,能够满… 相似文献
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有关瘤胃酸中毒发生机制研究表明,瘤胃乳酸的累积可能对酸中毒诱导起重要作用,而高精料日粮下瘤胃乳酸累积主要取决于瘤胃乳酸产生菌和乳酸利用菌间的平衡程度。本文综述了瘤胃微生物对乳酸的代谢机制,包括主要乳酸产生菌[溶纤维丁酸弧菌(Butyrivibrio fibrisolvens)、牛链球菌(Streptococcus bovis)、乳酸杆菌(Lactobacillus)]和主要乳酸利用菌[反刍兽新月单胞菌(Selenomonus ruminantium)、埃氏巨型球菌(Megasphaera elsdenii)],并简要概述了酸中毒的调控方法,旨在为反刍动物瘤胃酸中毒的乳酸中毒机制深入解析提供参考。 相似文献
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《饲料工业》2017,(5):42-47
试验以长白山地区6、7、8月及9月月初的紫穗槐作为试验样品,选取3头体况良好且相近、装有永久性瘤胃瘘管的延边黄牛为试验动物,通过对延边黄牛瘤胃体外发酵指标——pH值、氨态氮(NH_3-N)含量、总产气量、总甲烷产量、挥发性脂肪酸(VFA)含量的检测,探讨不同月份紫穗槐作为可直接饲喂的新型饲料资源对延边黄牛瘤胃发酵及甲烷产量的影响。结果表明:4个月份的紫穗槐在体外发酵过程中pH值均在正常范围内变化,且随着发酵时间的椎移呈下降趋势。发酵72 h后,7月紫穗槐体外瘤胃液中NH_3-N浓度、总产气量及产甲烷量显著低于8、9月份且显著高于6月份(P<0.05);6、7月紫穗槐组的乙酸、丙酸摩尔比显著高于8、9月紫穗槐组(P<0.05)。鉴于紫穗槐的收割时期对牧草收割量及对延边黄牛适口性的影响,综上所述,紫穗槐在7月收割时可使其发挥较高的利用价值,相比于其他月份可适当提高VFA浓度、丙酸浓度以及NH_3-N浓度,优化瘤胃发酵环境,并有效降低甲烷的排放,同时减少能量损失,进而增加饲料的利用率。 相似文献
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When the feed of sheep was changed from hay to barley, there were hyperplastic changes in the ruminal epithelium. These were characterised by an increase in the rate of mitosis and by a very low incidence of single cell death (apoptosis). A subsequent abrupt change of diet from barley to hay resulted in atrophy of the ruminal epithelium. Atrophy was associated with a fall in the rate of mitosis, and a rise in the incidence of apoptosis which together caused regression of epithelial pegs. It is suggested that apoptosis may play an important role in the regulation of rumen epithelial cell populations and in the control of epithelial cell kinetics. 相似文献
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Two promising methods to remove the ciliate protozoa of the stomach of ruminants by simple alterations in the feeding system were examined in vivo with lambs and heifers in the present investigation. The use of pelleted concentrates fed ad libitum and of milk, especially of milk fat (cream), turned out to be effective against protozoa when given after few hours of fasting. Milk led to the defaunation of a great proportion of the animals supplied all at once in an amount of 5-10% of rumen fluid volume. With cream the amount could be lower according to the higher fat content. Defaunation with concentrate was found to be not dangerous only for animals adapted to intensive feeding sufficiently. Additionally, a series of in vitro experiments were carried out to evaluate the reasons for the anti-protozoal effects of these methods. Concentrates rich in starch had toxic effects against protozoa, which mainly derived out of the depression in ruminal pH. The formed lactic acid had further effects irrespective of pH. The addition of crude fibre, especially of cellulose or lignin, reduced or prevented the anti-protozoal effects of concentrate fed ad lib. This was not so with the addition of buffers. With milk the included fat was shown to be responsible for the anti-protozoal effects, while the other main constituents of milk were of no importance. 相似文献
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Four digestion experiments with 5 wethers each (Feeding: artificially dried grass; 0, 15, 30 or 60 mg lasalocid per animal and day), two short time experiments (Exp. 1: 3 rumen fistulated sheep; feeding; artificially dried grass; 0, 15, 30 or 60 mg lasalocid per animal and day; exp. 2: 20 bulls; feeding; 2 kg concentrates per animal and day; wheat straw ad libitum; 0, 150 or 300 mg lasalocid per animal and day) and one individual feeding experiment (24 bulls per group; duration: 279 days, feeding: 2 kg concentrates per animal and day, corn silage and whole barley-grass silage ad libitum; 0 or 100/200 mg lasalocid per animal and day) were carried out in order to investigate the influence of the ionophore lasalocid on digestibility, figures of rumen fermentation as well as fattening and slaughtering results of bulls. Higher doses of lasalocid (30 and 60 mg per animal and day) decreased significantly digestibility of organic matter (1.8 and 2.8 units) and crude fibre (5.8 and 7.2 units). Relative acetate (22 to 120 mmoles per mol) and butyrate concentration (23 to 58 mmoles per mol) were decreased and molar propionate concentration of rumen liquid (25 to 154 mmoles per mol) was increased depending on level of lasalocid supplementation. Lasalocid did not significantly influence the dry matter intake; daily weight gain and slaughtering results were increased (4.4 and 6.1%), energy efficiency was improved (3.8%). Effects of lasalocid are similar to that of monensin. A dose of 20 to 30 mg lasalocid per kg dry matter is recommended. 相似文献
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通过尼龙袋法测定了5种淀粉源饲料在瘤胃的降解率。结果显示,玉米和荞麦在瘤胃的有效降解率(60.0%和61.6%)低于燕麦、小麦和大麦(78.9%、75.4%、69.8%)(P<0.05);燕麦的可溶性淀粉含量比较高,大麦和小麦表现出在9h内已经达到大部分被降解。 相似文献