Fat Characteristics And Lipid Metabolome Analysis Of Mongolian Cattle And Simmental Cattle

Mongolian cattle were used as the research object to analyze the quality characteristics of adipose tissue and to explore the differences in lipid metabolism between yellow fat of Mongolian cattle and white fat of Simmental cattle.The18-month-old Mongolian cattle were selected,after slaughter,the ribs,groin,and longissimus dorsi fat were taken,and the white fat of Simmental cattle was used as the control group.The fat chromaticity,melting point,thiobarbituric acid reactive substances(TBARS),and fatty acid types and contents were determined.The longissimus dorsi fats of Mongolian cattle and Simmental cattle were taken as the research objects,using lipid metabolites analysis method,analyze the different metabolites and metabolic pathways between Mongolian cattle and Simmental cattle fat.The results are as follows:The yellowness value,melting point value and lipid oxidation degree of Mongolian cattle adipose tissue were significantly higher than Simmental cattle adipose tissue(p<0.05).Among the fatty acids detected in the adipose tissues of different parts of Simmental and Mongolian cattle,the fatty acids with high contents are palmitic acid,stearic acid and oleic acid.Among them,the contents of saturated fatty acids in Mongolian cattle was higher,while the contents of monounsaturated fatty acids and polyunsaturated fatty acids was lower.The differential metabolites and metabolic pathways of fat between Mongolian cattle and Simmental cattle were analyzed.6922 metabolites were determined by MS1 and 142 metabolites were determined by MS2.Through multivariate statistical method,the metabolites were analyzed according to VIP? 1.0,Ratio ? 2 or Ratio ? 0.5,and q-value ? 0.05 as the threshold value.A total of 23 differential metabolites were screened out,of which 7 were up-regulated and 16 were down-regulated.Pathway enrichment analysis of differential metabolites was carried out by KEGG database,and 7 metabolic pathways were determined: linoleic acid metabolism,unsaturated fatty acid biosynthesis,?-linolenic acid metabolism,glycerol metabolism,glycerophospholipid metabolism,arachidonic acid metabolism,fatty acid biosynthesis metabolism.Among the 23 metabolites involved in the above metabolic pathways,myristic acid,linoleic acid,oleic acid,methyl dodecadienoate,phosphatidylcholine and lecithin were significantly different in two different adipose tissues(p < 0.05).The selected metabolites may play an important role in the lipid metabolism and energy metabolism and some metabolites may be the cause of yellow fat in Mongolian cattle.The intervention or regulation of lipid metabolism pathway may have a positive effect on Mongolian cattle's resistance to low temperature environment.The study determined the differential metabolism and key metabolic pathways of fat between Mongolian cattle and Simmental cattle,which laid the foundation for subsequent analysis combined with other omics.