Wang Lijun, Zhang Guangning, Li Yang, Zhang Yonggen
College of Animal Science and Technology, Qingdao agricultural university, No. 700 of Changcheng Road, Qingdao 266000, China.
College of Animal Science and Technology, Northeast Agricultural University, No. 600 of Changjiang Road, Harbin 150030, China.
Animals (Basel). 2020 Jan 30;10(2):223. doi: 10.3390/ani10020223.
The objectives of this study were to investigate the difference in the mechanism of VFAs production combined with macrogenome technology under different forage-to-concentrate ratios and sampling times. Six ruminally cannulated Holstein cows were used in a randomized complete block design. The high forage (HF) and high concentrate (HC) diets contained 70 and 35% dietary forage, respectively. The results showed that pH was affected by sampling time, at 4 h after feeding had lower value. Excepted for acetate, the VFAs was increased with forage decreased. Propionate formation via the succinic pathway, in which succinate CoA synthetase (EC 6.2.1.5) and propionyl CoA carboxylase (EC 2.8.3.1) were key enzymes, and significantly higher in HC treatment than in HF treatment, , , , and were the main microorganism that encodes these key enzymes. Butyrate formation via the succinic pathway, in which phosphate butyryltransferase (EC 2.3.1.19), butyrate kinase (EC 2.7.2.7) and pyruvate ferredoxin oxidoreductase (EC 1.2.7.1) are the important enzymes, and played important role in encodes these key enzymes. This research gave a further explanation on the metabolic pathways of VFAs, and microorganisms involved in VFAs production under different F:C ration, which could further reveal integrative information of rumen function.
本研究的目的是结合宏基因组技术，研究不同粗精比和采样时间下挥发性脂肪酸（VFA）产生机制的差异。采用随机完全区组设计，选用6头安装了瘤胃瘘管的荷斯坦奶牛。高粗饲料（HF）和高精饲料（HC）日粮分别含有70%和35%的日粮粗饲料。结果表明，pH值受采样时间影响，采食后4小时pH值较低。除乙酸外，VFA随着粗饲料减少而增加。通过琥珀酸途径形成丙酸，其中琥珀酰辅酶A合成酶（EC 6.2.1.5）和丙酰辅酶A羧化酶（EC 2.8.3.1）是关键酶，HC处理组的这些酶显著高于HF处理组， 、 、 、 和 是编码这些关键酶的主要微生物。通过琥珀酸途径形成丁酸，其中磷酸丁酰转移酶（EC 2.3.1.19）、丁酸激酶（EC 2.7.2.7）和丙酮酸铁氧还蛋白氧化还原酶（EC 1.2.7.1）是重要酶， 和 在编码这些关键酶中起重要作用。本研究进一步解释了VFA的代谢途径以及不同粗精比下参与VFA产生的微生物，这可以进一步揭示瘤胃功能的综合信息。
