Lameness is a very important disorder of periparturient dairy cows with implications on milk production and composition as well as with consequences on reproductive performance. The aetiology of lameness is not clear although there have been various hypotheses suggested over the years. The objective of this study was to metabotype the urine of dairy cows prior to, during and after the onset of lameness by evaluating at weeks −8, −4 pre-calving, the week of lameness diagnosis, and +4 and +8 weeks post-calving. We used a metabolomics approach to analyse urine samples collected from dairy cows around calving (6 cows with lameness v. 20 healthy control cows). A total of 153 metabolites were identified and quantified using an in-house MS library and classified into 6 groups including: 11 amino acids (AAs), 39 acylcarnitines (ACs), 3 biogenic amines (BAs), 84 glycerophospholipids, 15 sphingolipids and hexose. A total of 23, 36, 40, 23 and 49 metabolites were observed to be significantly different between the lame and healthy cows at −8 and −4 weeks pre-calving, week of lameness diagnosis as well as at +4 and +8 weeks post-calving, respectively. It should be noted that most of the identified metabolites were elevated; however, a few of them were also lower in lame cows. Overall, ACs and glycerophospholipids, specifically phosphatidylcholines (PCs), were the metabolite groups displaying the strongest differences in the urine of pre-lame and lame cows. Lysophosphatidylcholines (LysoPCs), although to a lesser extent than PCs, were altered at all time points. Alterations in urinary AA concentrations were also observed during the current study for four time points. During the pre-calving period, there was an observed elevation of arginine (−8 week), tyrosine (−8 week) and aspartate (−4 week), as well as a depression of urinary glutamate (−4 weeks). In the current study, it was additionally observed that concentrations of several sphingomyelins and one BA were altered in pre-lame and lame cows. Symmetric dimethylarginine was elevated at both −8 weeks pre-calving and the week of lameness diagnosis. Data showed that urinary fingerprinting might be a reliable methodology to be used in the future to differentiate lame cows from healthy ones.

me行是围产期奶牛的一种非常重要的疾病，它影响牛奶的生产和组成，并影响生殖性能。尽管多年来提出了各种假设，但of足病的病因尚不清楚。这项研究的目的是通过评估在−8周，产犊前−4周，诊断为the腿的那一周以及术后+4和+8周，对la牛发病之前，期间和之后的奶牛的尿进行代谢。 -产犊。我们用代谢组学方法分析奶牛收集各地产犊尿样（6头奶牛跛足v。20种健康对照牛）。使用内部MS库鉴定并定量了总共153种代谢物，并将其分为6组，包括：11个氨基酸（AAs），39个酰基肉碱（AC），3个生物胺（BA），84个甘油磷脂，15个鞘脂和己糖。在产犊前−8和−4周，dia​​gnosis行诊断周以及+4和+8周，the牛和健康奶牛之间总共观察到23、36、40、23和49种代谢物显着不同产后分娩。应当指出的是，大多数鉴定出的代谢产物都升高了。但是，其中一些也比me牛低。总体而言，AC和甘油磷脂，特别是磷脂酰胆碱（PC）是代谢产物组，它们在前lam足和me足母牛的尿液中表现出最强的差异。溶血磷脂酰胆碱（LysoPCs）虽然程度不如PCs，但在所有时间点都发生了改变。在当前研究的四个时间点也观察到尿液AA浓度的变化。在产犊前，观察到精氨酸（−8周），酪氨酸（−8周）和天冬氨酸（−4周）升高，尿谷氨酸降低（−4周）。在当前研究中，还观察到前lam脚和la脚母牛的几种鞘磷脂和一种BA的浓度发生了变化。产犊前-8周和diagnosis行诊断周均增加了对称的二甲基精氨酸。