Amanullah Sardar Muhammad, Kim Dong Hyeon, Paradhipta Dimas Hand Vidya, Lee Hyuk Jun, Joo Young Hoo, Lee Seong Shin, Kim Eun Tae, Kim Sam Churl
Division of Applied Life Science (BK21Four), Institute of Agriculture and Life Science, Gyeongsang National University, Jinju, South Korea.
Biotechnology Division, Bangladesh Livestock Research Institute, Savar, Bangladesh.
Front Microbiol. 2021 Mar 11;12:637220. doi: 10.3389/fmicb.2021.637220. eCollection 2021.
This study estimated the effect of essential fatty acid (FA) supplementation on fermentation indices, greenhouse gases, microbes, and FA profiles in the rumen. The treatments used pure FAs consisting of C18:2n-6 FA (LA), C18:3n-3 FA (LNA), or a mixture of these FAs at 1:1 ratio (Combo). rumen incubation was performed in 50 mL glass serum bottles containing 2 mg of pure FAs, 15 mL of rumen buffer (rumen fluid+anaerobe culture medium = 1:2), and 150 mg of synthetic diet (411 g cellulose, 411 g starch, and 178 g casein/kg dry matter) at 39°C for 8 h with five replications and three blanks. In rumen fermentation indices, LA exhibited highest ( < 0.05) ammonia-N and total gas volume after 8 h of incubation. Furthermore, LA presented lower ( < 0.05) pH with higher ( < 0.05) total volatile fatty acid ( = 0.034) than Combo, while LNA was not different compared with those in the other treatments. Additionally, Combo produced highest ( < 0.05) CO with lowest ( < 0.05) CH. In the early hours of incubation, LA improved ( < 0.005) and , while LNA improved ( < 0.005) . After 8 h of incubation, LNA had lower ( < 0.05) methanogenic archaea than LA and Combo but had higher ( < 0.05) rumen ciliates than LA. was higher ( < 0.05) in LA than in LNA and Combo. It was observed that the rate of biohydrogenation of n-6 and n-3 FAs was comparatively lowest ( < 0.05) in Combo, characterized by higher C18:2n-6 and/or C18:3n-3 FA and polyunsaturated FA (PUFA) concentrations with lower ( < 0.05) concentrations of C18:0 and saturated FA and the ratio of saturated FAs to PUFAs. Therefore, this study concluded that dietary C18:2n-6 could improve populations of fibrolytic bacteria and rumen fermentation indices, but dietary mixture of pure C18:2n-6 and C18:3n-3 is recommended because it is effective in reducing enteric methane emissions and resisting biohydrogenation in the rumen with less effect on rumen microbes.
本研究评估了补充必需脂肪酸（FA）对瘤胃发酵指标、温室气体、微生物及脂肪酸谱的影响。试验处理使用了纯脂肪酸，包括C18:2n-6脂肪酸（亚油酸，LA）、C18:3n-3脂肪酸（亚麻酸，LNA），或这两种脂肪酸按1:1比例混合的混合物（组合脂肪酸，Combo）。在50 mL玻璃血清瓶中进行瘤胃培养，瓶中含有2 mg纯脂肪酸、15 mL瘤胃缓冲液（瘤胃液+厌氧菌培养基 = 1:2）和150 mg合成日粮（411 g纤维素、411 g淀粉和178 g酪蛋白/kg干物质），于39℃培养8 h，设5个重复和3个空白。在瘤胃发酵指标方面，培养8 h后，LA组的氨氮和总气体体积最高（P<0.05）。此外，LA组的pH较低（P<0.05），总挥发性脂肪酸含量较高（P = 0.034），高于组合脂肪酸组，而LNA组与其他处理组相比无差异。此外，组合脂肪酸组产生的二氧化碳最高（P<0.05），甲烷最低（P<0.05）。在培养初期，LA组提高了（P<0.005）[此处原文缺失具体指标]，而LNA组提高了（P<0.005）[此处原文缺失具体指标]。培养8 h后，LNA组的产甲烷古菌数量低于LA组和组合脂肪酸组（P<0.05），但瘤胃纤毛虫数量高于LA组（P<0.05）。LA组的[此处原文缺失具体指标]高于LNA组和组合脂肪酸组（P<0.05）。观察发现，组合脂肪酸组中n-6和n-3脂肪酸的生物氢化速率相对最低（P<0.05），其特征是C18:2n-6和/或C18:3n-3脂肪酸及多不饱和脂肪酸（PUFA）浓度较高，C18:0和饱和脂肪酸浓度较低（P<0.05），饱和脂肪酸与PUFA的比例较低。因此，本研究得出结论，日粮中的C18:2n-6可改善纤维分解菌数量和瘤胃发酵指标，但建议使用纯C18:2n-6和C18:3n-3的日粮混合物，因为它能有效减少肠道甲烷排放并抵抗瘤胃中的生物氢化作用，对瘤胃微生物的影响较小。
