Abstract: 【Objective】 The objective of this experiment is to study the effect of lipopolysaccharide (LPS) on metabolism of dairy goat liver, explore the characteristic metabolites in the liver and clarify the mechanism of hepatic dysbolism caused by LPS.【Method】Total 15 Guanzhong dairy goats of 12-month-old with 24-28 kg live body weight (BW) were selected and divided into three groups randomly, i.e. control group (CTL, goat No. 1-5), LPS-L group (LPS-L, goat No. 6-10) and LPS-H group (LPS-H, goat No.11-15). Animals were fed total mixed ration (TMR) made according to NRC (2007). The experimental goats were fed with feeds and water ad libitum. After 14d adaption, the experiment was conducted. At the beginning of the experiment (0 h), the goats in LPS-L and LPS-H were given 20 and 40μg·kg^-1 BW of LPS solution via intraperitoneal injections, respectively. The goats in CTL were received same volume of saline water. 24 h later, goats in each LPS treatment groups were added LPS solution once again. 48 h later from the beginning, blood samples were drawn from jugular vein and were centrifuged to extract plasma for biochemical determination. Subsequently, the goats’ liver tissue samples were collected by biopsy and marked and stored in liquid nitrogen. ¹H-NMR metabonomics was used to research the changes of metabolites in goat liver, the obtained metabolites. The data variables (concentration value of metabolites) were analyzed by the software of partial least squares discriminant analysis (PLS-DA) installed in the equipment to identify metabolic differences between the groups of each treatment. 【Result】Serum biochemical results showed that the concentration of ALT, AST and TBIL increased significantly, while TG, TC, VLDL, NEFA, HDL, LDL, ALB, TP decreased to different degrees in LPS treated groups compared with that of CTL, indicating the goats liver were injured to some degrees and the dysbolism was occurred in goat liver. With the ¹H-NMR metabonomics determination, totally 69 metabolites were detectedbased on its identification database of Chenomx. After the metabolite variables analyzing using PLS-DA, it showed that the CTL, LPS-L and LPS-H groups could be clustered and distinguished based on the metabolomic data analysis. Nine out of 69 metabolites differed significantly among the three groups. Based on the statistics and analysis between any two of the groups, 6 metabolites located in LPS-L and LPS-H groups were notable compared with the CTL, and 3 metabolites were different significantly between LPS-L and LPS-H. Further analysis indicated that these metabolites were related to amino acid metabolism, fat metabolism and carbohydrate metabolism in the liver.【Conclusion】In conclusion, LPS induced significant changes in liver reflected in blood biochemical indices. Metabolomics profile could precisely detect characteristic metabolites and effectively distinguish LPS-L and LPS-H from CTL effectively. Metabolomic technology could clarify the mechanism for liver dysbolism suffering from LPS and provide enough information to diagnose liver injury via analyzing the relevant pathway.

Key words: metabolomics, lipopolysaccharide, liver, metabolite, dairy goat