~H-NMR Based Plasma Metabolic Profiling Of Dairy Cows Suffered From Ovary Standstill

Postpartum anestrus in dairy cow refers to no obvious estrous signs and non-cyclicalovarian function and activity during early lactation (usually60-90days postpartum) until theirgenitals return to normal, which is a common breeding problem of dairy cow postpartum. In therecent years, the bigger of the scale and milk yield of dairy farm was, the more anestrus of cowpostpartum was, and it brought huge economic losses to dairy farm. Although anestrus of cowspostartum is related to many factors, including nutrition, metabolism, endocrine and so on, therelevant relationship between anestrus of dairy cows postpartum and the whole body metabolismis still unclear. Therefore, in this experiment, the theory and technology of metabolomics,namely1H Nuclear Magnetic Resonance (1H NMR), combined with multivariate statisticalanalysis and bioinformatics analysis were applied to obtain characteristic metabolites in plasmafrom anestrous cows postpartum due to ovarian stationary and clarify the relationship betweencharacteristic metabolites and anestrus of cows postpartum. It will provide the scientific basis forfurther revealing metabolic mechanism of anestrus of cows postpartum in the future.In this trial,206healthy cows, which had similar age, parity and body condition and milkyield (more than10tons per year), were randomly selected60to90days postpartum from anintensive dairy farm in Heilongjiang Province as the test animals. According to the clinicalmanifestations, the B-ultrasound scan, rectal examination and hormone tests,10cows wereassigned into estrous group (E) and10cows into anestrous group (A). All plasma samples fromtwo groups of cows were detected by unbiased1H NMR spectroscopy to contrast plasmametabolomic profiles between groups, and combined with multivariate pattern recognitionincluded principal component analysis (PCA), partial least squares-discriminant analysis(PLS-DA), and orthogonal correction partial least squares-discriminant analysis (OPLS-DA),different metabolites in plasma of anestrus cow were screened and identified throughbioinformatics analysis.Results showed that compared with normal estrous cows,12kinds of metabolites in plasmaof aneostrus cows postpartum were abnormal, including an increase of acetic acid, citric acid andtyrosine, and a decrease of low-density lipoprotein, very low density lipoproteins, lipids, alanine,pyruvate, creatine, choline, phosphorylcholine and glycerophosphorylcholine; These metaboliteswere closely related to abnormality of glucose metabolism, amino acid metabolism, lipoproteinmetabolism and choline metabolism, respectively involved in cyanide amino acid metabolicpathway, pyruvate metabolism (or glycolysis and gluconeogenesis) pathway, glycine, serine andthreonine metabolism (or Krebs cycle) pathway, the citric acid cycle (TCA cycle) pathway, glycine, serine and threonine pathway, glycerol phospholipid metabolism and glycine, serine andthreonine metabolism pathway, glycerol phospholipid metabolism pathway, glycerolphospholipid metabolism pathways, ubiquinone biosynthesis and other terpenoids andphenylalanine, tyrosine and tryptophan biosynthesis pathway, may disturb the normal estrus; Atthe same time, anestrous cows were often in condition of negative energy balance, which may beaccompanied by ketosis or fatty liver. The decrease of plasma creatine and choline concentrationand the increase of tyrosine concentration were new changes for anestrus of cows postpartum.Conclusion obtained that1H NMR techniques combined with multivariate statisticalanalysis can effectively discovery different metabolites in plasma of anestrous cows postpartum,and reveal a panoramic metabolism changes of anestrous cows postpartum. It will lay thetheoretical and methodological foundation for further study of anestrus of cows postpartum.