Rojas-Gómez Paula, Pariyani Raghunath, Bateman Lorraine M, Lynch Denis, Timlin Mark, Dineen Michael, McCarthy Noel A, Brodkorb André, Maguire Anita R, O'Donovan Michael, Hennessy Deirdre, Murphy Thomas Brendan, O'Mahony James A, O'Callaghan Tom F
School of Food and Nutritional Sciences, University College Cork, Cork, T12 Y337, Ireland.
School of Chemistry, Analytical and Biological Chemistry Research Facility, SSPC, Research Ireland Centre for Pharmaceuticals, University College Cork, Cork, T12 YN60, Ireland; School of Pharmacy, University College Cork, Cork, T12 K8AF, Ireland.
J Dairy Sci. 2025 May;108(5):4659-4673. doi: 10.3168/jds.2024-26168. Epub 2025 Mar 24.
This study investigates the effect of varying proportions of pasture (high, medium, no-pasture) in the diet of cows and seasonality on the milk metabolome throughout lactation using proton nuclear magnetic resonance (H-NMR) spectroscopy. This study explored the potential to differentiate milks from varying levels of pasture in the cow's diet and highlight potential biomarkers for authentication. A total of 54 spring calving cows were assigned to the 3 diet treatments for the duration of lactation. Weekly bulk milk samples were collected from each herd. Over 37 wk (March-November 2020), 43 metabolites representing diverse chemical classes, including AA and nitrogenous compounds, carbohydrates, VFA, organic acids, and alcohols were quantified. Significant dietary and seasonal influences on the milk metabolome were characterized, with signature differences attributed to the proportion of pasture in the cow's diet and the season of milk production. Receiver operating characteristic analysis of the milk from different feeding systems across lactation highlighted the potential of the milk metabolome to distinguish pasture from nonpasture-derived milks, with a series of metabolites demonstrated as excellent biomarkers, including hippurate. Multivariate analysis also highlighted dimethyl sulfone as a key metabolite for the distinction between different diet regimens. These findings highlight the diversity and complexity of the composition of milk as affected by seasonality, and signature characteristics that are associated with pasture-based feedings systems. As "grass-fed" dairy products become more prominent on the market, the analysis of the milk metabolome using H-NMR shows significant promise for utilization as a tool for authentication purposes.
本研究采用质子核磁共振（H-NMR）光谱法，调查了奶牛日粮中不同比例的牧场草（高、中、无牧场草）以及季节性因素对整个泌乳期牛奶代谢组的影响。本研究探索了区分奶牛日粮中不同牧场草水平的牛奶的潜力，并突出了用于鉴别的潜在生物标志物。总共54头春季产犊的奶牛在整个泌乳期被分配到3种日粮处理组。每周从每个牛群中采集混合牛奶样本。在37周（2020年3月至11月）期间，对代表不同化学类别的43种代谢物进行了定量分析，这些代谢物包括氨基酸和含氮化合物、碳水化合物、挥发性脂肪酸、有机酸和醇类。研究确定了日粮和季节对牛奶代谢组有显著影响，其特征性差异归因于奶牛日粮中牧场草的比例和产奶季节。对不同饲养系统在整个泌乳期的牛奶进行的受试者工作特征分析突出了牛奶代谢组区分牧场草来源和非牧场草来源牛奶的潜力，一系列代谢物被证明是优秀的生物标志物，包括马尿酸盐。多变量分析还突出了二甲基砜是区分不同日粮方案的关键代谢物。这些发现突出了受季节性影响的牛奶成分的多样性和复杂性，以及与以牧场草为基础的饲养系统相关的特征性特点。随着“草饲”乳制品在市场上变得更加突出，使用H-NMR对牛奶代谢组进行分析显示出作为一种鉴别工具的巨大潜力。
