奶牛围产后期血液代谢物动态变化规律研究

Study on Dynamic Change Rules of Blood Metabolites in Dairy Cows during Late Perinatal Period

本试验旨在揭示奶牛围产后期血液代谢物动态变化规律,为围产后期营养调控和代谢性疾病的预防提供参考依据。选取体况相近、胎次相同的荷斯坦奶牛7头,尾静脉采集产后0(分娩当天)、7、14和21 d血液样本,制备血浆,进行超高液相色谱-串联质谱(UPLC-MS/MS)代谢组学和代谢通路分析。结果表明:1)奶牛产后7、14和21 d血液代谢轮廓较产后0 d发生了明显改变,而产后7、14和21 d之间相比,血液代谢轮廓未发生明显变化。2)与产后0 d相比,产后7 d能量代谢相关代谢物丙酮酸、L-乳酸、D-葡萄糖和甜菜碱相对含量显著下调[P<0.05,变量重要性投影(VIP)≥1,差异倍数(FC)≤0.5],脂代谢相关代谢物肉碱C11∶DC、肉碱C12∶1、肉碱C13∶0等和氧化三甲胺(TMAO)相对含量显著下调(P<0.05,VIP≥1,FC≤0.5),氧化应激相关代谢物还原型谷胱甘肽和L-半胱氨酸相对含量显著下调(P<0.05,VIP≥1,FC≤0.5),肾上腺素和皮质醇相对含量显著下调(P<0.05,VIP≥1,FC≤0.5),胆汁酸代谢相关代谢物甘氨胆酸、甘氨脱氧胆酸、23-脱甲脱氧胆酸和甘氨鹅脱氧胆酸含量显著上调(P<0.05,VIP≥1,FC≥2)。研究结果表明,围产后期奶牛处于代谢应激和氧化应激状态,为奶牛产后护理提供了相关理论依据。

The purpose of this experiment was to reveal the dynamic change rules of blood metabolites in dairy cows during late perinatal period,and to provide reference for nutritional regulation and prevention of metabolic diseases in the late perinatal period.Seven Holstein dairy cows with similar body condition and the same parity were selected.Postpartum blood samples at 0(day of delivery),7,14 and 21 d were collected from the tail vein to prepare plasma,and metabolomics by ultra-high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS)and metabolic pathways were analyzed.The results showed as follows:1)the blood metabolic profile of dairy cows at postpartum 7,14 and 21 d was significantly changed compared with postpartum 0 d,but there was no significant change between postpartum 7,14 and 21 d.2)Compared with postpartum 0 d,the relative contents of related metabolites of energy metabolism such as pyruvate,L-lactic acid,D-glucose and betaine at postpartum 7 d were significantly decreased[P<0.05,variable importance in projection(VIP)≥1,fold change(FC)≤0.5];the relative contents of related metabolites of lipid metabolism such as carnitine C11∶DC,carnitine C12∶1,carnitine C13∶0 and trimethylamine oxide(TMAO)were significantly decreased(P<0.05,VIP≥1,FC≤0.5),the relative contents of related metabolites of oxidative stress such as reduced glutathione and L-cysteine were significantly decreased(P<0.05,VIP≥1,FC≤0.5),the relative contents of epinephrine and cortisol were significantly decreased(P<0.05,VIP≥1,FC≤0.5),and the contents of related metabolites of bile acid metabolism such as glycocholic acid,glycine deoxycholic acid,23-deoxydeoxycholic acid and glycochenodeoxycholic acid were significantly increased(P<0.05,VIP≥1,FC≥2).In conclusion,the results show that daily cows are in the state of metabolic stress and oxidative stress in the late perinatal period,which provides relevant a theoretical basis for postpartum nursing of daily cows.