Lipid metabolomics reveals metabolic responses of subcutaneous fat in yaks under different feeding conditions during the cold season

The aim of this experiment was to investigate the differences in subcutaneous fat metabolism expression in yaks under natural grazing and housed feeding conditions in the cold season. Eighteen 18-month-old yaks with similar body weights and non-significant differences in dorsal subcutaneous fat were randomly divided into three groups.

One group (G18_SF) of yaks was selected for slaughter at the beginning of the experiment (October), one group continued to graze for 6 months and then slaughtered (G24_SF) and one group was housed for 6 months and then slaughtered (F24_SF) and subcutaneous dorsal fat of the three groups was collected for metabolomic analysis, screening of differential metabolites and enrichment of KEGG pathway.

In this experiment, 110 differential metabolites were detected in G24_SF vs F24_SF and 83 metabolites were screened for down-regulation and 27 metabolites were up-regulated and the differential metabolites were mainly enriched in Alanine, aspartate and glutamate metabolism, Arachidonic acid metabolism and D-Glutamine and D-glutamate metabolism pathways. Ninety-seven differential metabolites were detected in G18_SF vs G24_SF and 41 metabolites were screened for down-regulation and 56 metabolites were screened for up-regulation, with the two groups of differential metabolites mainly enriched in Alanine, aspartate and glutamate metabolism, caffeine metabolism and starch and sucrose metabolism pathways. The results of this experiment revealed the information of differential metabolites and enrichment pathways of yak fat in different feeding methods and different months of age and laid the foundation for further in-depth study of subcutaneous fat deposition in yaks.