State Key Laboratory of Animal Nutrition, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China.
Appl Environ Microbiol. 2022 Mar 22;88(6):e0190821. doi: 10.1128/AEM.01908-21. Epub 2022 Jan 26.
3-Nitrooxypropanol (3-NOP) is effective at reducing ruminal methane emissions in ruminants. But it also causes a drastic increase in hydrogen accumulation, resulting in feed energy waste. Fumarate is a key precursor for propionate formation and plays an important role in rumen hydrogen metabolism. Therefore, this study examined the effects of 3-NOP combined with fumarate on volatile fatty acids, methanogenesis, and microbial community structures in dairy cows . The culture experiment was performed using a 2-by-2 factorial design, two 3-NOP levels (0 or 2 mg/g dry matter [DM]) and two fumarate levels (0 or 100 mg/g DM), including 3 runs with 4 treatments, 4 replicates, and 4 blanks containing only the inoculum. Rumen fluid was collected from three lactating Holstein cows with permanent ruminal fistulas. The combination of 3-NOP and fumarate reduced methane emissions by 11.48% without affecting dry matter degradability. The propionate concentration increased and the acetate/propionate ratio decreased significantly. In terms of bacteria, the combination of 3-NOP and fumarate reduced the abundances of and and increased the abundances of and . For archaea, the combination of 3-NOP and fumarate significantly increased the abundances of r_sp._AbM4, while the abundance of operational taxonomic unit 581 (OTU581) (belonging to an strain) was significantly decreased. These results indicated that the combination of 3-NOP and fumarate could alleviate the accumulation of hydrogen and enhance the inhibition of methanogenesis compared with 3-NOP only in dairy cows. The global problem of climate change and the greenhouse effect has become increasingly severe, and the abatement of greenhouse gases has received great attention from the international community. Methane produced by ruminants during digestion not only aggravates the greenhouse effect but also causes a waste of feed energy. As a methane inhibitor, 3-nitrooxypropanol can effectively reduce methane emissions from ruminants. However, when it inhibits methane emissions, the emission of hydrogen increases sharply, resulting in the waste of feed resources. Fumarate is a propionic acid precursor that can promote the metabolism of hydrogen to propionic acid in animals. Therefore, we studied the effects of the combined addition of 3-nitrooxypropanol and fumarate on methanogenesis, rumen fermentation, and rumen flora. It is of great significance to inhibit methane emission from ruminants and slow down the greenhouse effect.
3-硝基氧基-1-丙醇（3-NOP）在反刍动物中可有效减少瘤胃甲烷排放。但它也会导致氢气大量积累，从而浪费饲料能量。富马酸是丙酸盐形成的关键前体，在瘤胃氢代谢中起着重要作用。因此，本研究探讨了 3-NOP 与富马酸联合应用对奶牛挥发性脂肪酸、甲烷生成和微生物群落结构的影响。该培养实验采用 2×2 析因设计，设 3-NOP 水平（0 或 2mg/g 干物质[DM]）和富马酸水平（0 或 100mg/g DM）两个因素，每个因素 3 个水平，共 4 个处理，每个处理重复 4 次，空白对照 4 个，仅含接种物。从 3 头具有永久性瘤胃瘘管的泌乳荷斯坦奶牛中采集瘤胃液。3-NOP 和富马酸的组合可使甲烷排放量减少 11.48%，而不影响干物质降解率。丙酸浓度显著增加，乙酸/丙酸比显著降低。在细菌方面，3-NOP 和富马酸的组合降低了 和 的丰度，增加了 和 的丰度。在古菌方面，3-NOP 和富马酸的组合显著增加了 r_sp._AbM4 的丰度，而 OTU581（属于 菌株）的丰度显著降低。这些结果表明，与单独使用 3-NOP 相比，3-NOP 和富马酸的组合可以减轻奶牛体内氢气的积累，增强对甲烷生成的抑制作用。全球气候变化和温室效应问题日益严峻，减少温室气体排放受到国际社会的广泛关注。反刍动物在消化过程中产生的甲烷不仅加剧了温室效应，还造成了饲料能量的浪费。3-硝基氧基-1-丙醇作为一种甲烷抑制剂，可有效降低反刍动物的甲烷排放量。然而，当它抑制甲烷排放时，氢气的排放量会急剧增加，导致饲料资源的浪费。富马酸是丙酸的前体物质，可促进动物体内的氢气向丙酸转化。因此，我们研究了 3-硝基氧基-1-丙醇和富马酸联合添加对甲烷生成、瘤胃发酵和瘤胃菌群的影响。这对于抑制反刍动物甲烷排放、减缓温室效应具有重要意义。
