College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, People's Republic of China.
College of Animal Science and Technology, Zhejiang Agriculture and Forestry University, Lin'an, Hangzhou, Zhejiang 311300, People's Republic of China.
J Agric Food Chem. 2020 Nov 18;68(46):13154-13159. doi: 10.1021/acs.jafc.9b07453. Epub 2020 Mar 25.
This experiment was conducted to investigate the effects of dietary rumen-protected betaine (RPB) supplementation, as partial replacement for methionine, on the lactation performance of mid-lactation dairy cows. A total of 36 Holstein dairy cows were randomly assigned to three groups [control, 20 g/day RPB, or 15 g/day rumen-protected methionine (RPM)]. The experiment was conducted over 9 weeks, with the first week for adaptation. Blood metabolites were analyzed with metabolomics in the control and RPB groups. The results revealed that the milk yield and milk protein content were higher in cows fed RPB and RPM compared to those in the control group. Concentrations of nine metabolites differed between cows in the RPB and control groups. These metabolites were mainly concentrated in six pathways, such as arginine synthesis and proline degradation and cyanoamino acid synthesis. This study revealed that RPB can spare methionine and improve lactation performance of dairy cows fed with diets moderately deficient in methionine.
本实验旨在研究日粮保护性甜菜碱（RPB）作为蛋氨酸部分替代物对泌乳中期奶牛泌乳性能的影响。将 36 头荷斯坦奶牛随机分为三组[对照组、20 g/天 RPB 组或 15 g/天保护甲硫氨酸（RPM）组]。实验进行了 9 周，其中第一周为适应期。采用代谢组学方法分析对照组和 RPB 组奶牛的血液代谢产物。结果表明，与对照组相比，饲喂 RPB 和 RPM 的奶牛产奶量和乳蛋白含量更高。RPB 组和对照组奶牛的 9 种代谢物浓度存在差异。这些代谢物主要集中在六个途径，如精氨酸合成和脯氨酸降解和氰基氨基酸合成。本研究表明，RPB 可以节省蛋氨酸并改善蛋氨酸中度缺乏日粮奶牛的泌乳性能。
