Southern Regional Station, ICAR-National Dairy Research Institute, Adugodi, Bangalore, 560030, India.
Center for Systems Biology and Molecular Medicine, Yenepoya Research Centre, Yenepoya (Deemed to be University), Mangalore, 575018, India.
Sci Rep. 2021 Feb 2;11(1):2831. doi: 10.1038/s41598-021-82412-z.
The milk and milk products from cows reared under grazing system are believed to be healthier and hence have high demand compared to milk from cows reared in the non-grazing system. However, the effect of grazing on milk metabolites, specifically lipids has not been fully understood. In this study, we used acetonitrile precipitation and methanol:chloroform methods for extracting the milk metabolites followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) run to identify the different metabolites between the milk of grazing and non-grazing early lactating Malnad Gidda cows. Various carbohydrates, amino acids, nucleosides and vitamin derivatives were found to be differentially abundant in grazing cows. A total of 35 metabolites were differentially regulated (fold change above 1.5) between the two groups. Tyrosyl-threonine, histidinyl-cysteine, 1-methyladenine, L-cysteine and selenocysteine showed fold change above 3 in grazing cows. The lipid profile of milk showed a lesser difference between grazing and non-grazing cows as compared to polar metabolites. To the best of our knowledge, this is the largest inventory of milk metabolomics data of an Indian cattle (Bos indicus) breed. We believe that our study would help to emerge a field of Nutri-metabolomics and veterinary omics research.
人们认为，与非放牧系统饲养的奶牛所产的牛奶相比，放牧系统饲养的奶牛所产的牛奶和奶制品更健康，因此需求量更大。然而，放牧对牛奶代谢物（特别是脂质）的影响尚未完全了解。在这项研究中，我们使用乙腈沉淀和甲醇：氯仿法提取牛奶代谢物，然后进行液相色谱-串联质谱（LC-MS/MS）分析，以确定放牧和非放牧泌乳早期马纳迪吉达奶牛牛奶中的不同代谢物。结果发现，放牧奶牛中各种碳水化合物、氨基酸、核苷和维生素衍生物的丰度存在差异。两组之间有 35 种代谢物存在差异调节（倍数变化大于 1.5）。酪氨酸-苏氨酸、组氨酰-半胱氨酸、1-甲基腺嘌呤、L-半胱氨酸和硒代半胱氨酸在放牧奶牛中的倍数变化大于 3。与极性代谢物相比，放牧和非放牧奶牛的牛奶脂质谱差异较小。据我们所知，这是印度牛（Bos indicus）品种牛奶代谢组学数据的最大清单。我们相信，我们的研究将有助于出现营养代谢组学和兽医组学研究领域。
