Background: As the milk production of dairy cows increases, the reproductive capacity gradually declines. Ovarian quiescence has become one of the concerns of the dairy industry.

Objective: To explore the different plasma metabolite levels between estrus and anestrus in energy balanced (EB) dairy cows.

Methods: Ten estrous and 10 anestrus EB Holstein cows in early lactation were selected for the study. ¹H nuclear magnetic resonance technology was used to detect plasma metabolites and screen different plasma metabolites between anestrous and estrous cows at 60–90 days postpartum using multivariate statistical analysis.

Results: Within an elective waiting period of 60−90 days postpartum mean plasma concentration of total estrogens was significantly higher in estrus cows as compared to anestrus cows (71.2 ± 26.0 and 42.4 ± 16.7 pg/mL, respectively). Seven plasma metabolites (isoleucine, leucine, valine, alanine, arginine, choline and phosphatecholine) demonstrated significant decreases in estrous dairy cows relative to anestrous subjects. The main pathway was leucine, isoleucine and valine biosynthesis.

Conclusion: Anestrus in dairy cows is accompanied by alterations in amino acid, glucose and lipid metabolism based on ¹H NMR analysis.

背景：随着奶牛产奶量的增加，生殖能力逐渐下降。卵巢静止已经成为乳业关注的问题之一。

目的：探讨能量平衡（EB）奶牛发情和发情之间血浆代谢物水平的不同。

方法：选择泌乳初期的10头发情牛和10头发情期EB荷斯坦奶牛进行研究。¹ H核磁共振技术用于通过多元统计分析在产后60-90天时检测发情和发情奶牛之间的血浆代谢物并筛选不同的血浆代谢物。

结果：在产后60-90天的选择性等待期内，发情母牛的总雌激素平均血浆浓度比发情母牛高（分别为71.2±26.0和42.4±16.7 pg / mL）。与发情的受试者相比，发情的奶牛有七种血浆代谢物（异亮氨酸，亮氨酸，缬氨酸，丙氨酸，精氨酸，胆碱和磷酸盐胆碱）表现出明显的减少。主要途径是亮氨酸，异亮氨酸和缬氨酸的生物合成。

结论：基于¹ H NMR分析，奶牛的发情期伴随着氨基酸，葡萄糖和脂质代谢的改变。