水牛泌乳期与干乳期差异血清生化指标及代谢物研究

Studies on Serum Biochemical Indices and Metabolites Differing Between Lactation and Dry Periods in Buffaloes

本研究旨在比较泌乳期与干乳期水牛(Bubalus bubalis)差异血清生化指标及差异血清代谢物的组成,探讨血清生化指标与代谢物的相互关联,进一步了解水牛营养代谢过程的调控机制。选取泌乳期(泌乳第100~200天)健康水牛9头和干乳期(停乳后第30~60天)健康水牛9头,每头牛采血清样本两份,一份用生化分析仪进行20项指标检测;另一份用超高效液相色谱-串联质谱法(ultra-high performance liquid chromatography-tandem mass spectrometry,UPLC-MS/MS)检测分析水牛血清中内源性代谢物。在生化指标检测结果中,泌乳期的谷草转氨酶/谷丙转氨酶(P<0.05)、甘油三酯(P<0.01)显著低于干乳期的,说明水牛在泌乳期时对酯类物质的利用效率更高;而泌乳期的胆固醇(P<0.01)、低密度脂蛋白(P<0.01)、高密度脂蛋白(P<0.001)、尿素氮(P<0.01)、葡萄糖(P<0.01)和免疫球蛋白A(P<0.0001)等指标显著高于干乳期的,说明泌乳期时水牛的物质代谢更高。对于血清代谢物进行分析得出共有183种代谢产物在2个时期中存在显著差异(P<0.05,VIP>1),这些代谢产物共富集到8条显著不同的代谢途径,分别是D-谷氨酰胺和D-谷氨酸代谢,精氨酸和脯氨酸代谢,色氨酸代谢,卟啉和叶绿素代谢,甘氨酸、丝氨酸和苏氨酸代谢,组氨酸代谢,不饱和脂肪酸的生物合成,以及氮代谢(P<0.05)。这些结果说明在泌乳期时,水牛吸收的营养物质主要用于参与多种氨基酸的合成及脂肪酸的合成与利用。

This study aims to compare various serum biochemical indices and the composition of serum metabolites in buffaloes(Bubalus bubalis)during lactation and dry periods.Additionally,it seeks to investigate the correlation between serum biochemical indices and metabolites to enhance our understanding of the regulatory mechanisms governing nutritional metabolism in buffaloes.The study selected nine healthy buffaloes in the lactation period(the 100th to 200th day of lactation)and nine in the dry period(the 30th to 60th day after stopping breastfeeding).Two serum samples were collected from each buffalo.One of the collected serum samples from each buffalo was analyzed using a biochemical analyzer to quantify 20 indices.The other sample was subjected to ultra-high performance li-quid chromatography-tandem mass spectrometry(UPLC-MS/MS)to identify and quantify endogenous metabolites in the buffalo serum.Among the biochemical index detection results,the glutamic-oxaloacetic transaminase/glutamic-pyruvic transaminase(P<0.05)and triglycerides(P<0.01)in the lactation period were significantly lower than those in the dry period,indicating that the utilization efficiency of esters in buffalo during lactation was higher.Cholesterol(P<0.01),low-density lipoprotein(P<0.01),high-density lipoprotein(P<0.001),urea nitrogen(P<0.01),glucose(P<0.01),and immunoglobulin A(P<0.0001)were significantly higher in the lactation period than those in the dry period,indicating that the substance metabolism of buffalo during lactation was higher.The metabolomic analysis of the serum revealed that a total of 183 metabolites exhibited significant differences between the two periods under study(P<0.05,VIP>1).These metabolites were enriched in 8 significantly different metabolic pathways,including D-glutamine and D-glutamate metabolism,arginine and proline metabolism,tryptophan metabolism,porphyrin and chlorophyll metabolism,glycine,serine and threonine metabolism,histidine metabolism,biosynthesis of unsaturated fatty acids and nitrogen metabolism(P<0.05).These results show that during the lactation period,the nutrients absorbed by buffalo are mainly used to participate in the synthesis of various amino acids and the synthesis of fatty acids.