Effects of early experience with low-quality roughage on liver metabolome in lambs

Introduction Early experience with low-quality roughage has the potential to improve its utilization in ruminants. Objectives This study determined the effects of early experience with low-quality roughage on dry matter intake (DMI), body weight (BW) and the hepatic metabolism of lambs. Methods Ten lambs (3 month old) were randomly allocated to two treatments: the low-quality roughage group (LR) or the control group (C). The study lasted 7 months. In the first 4 months, LR was fed low-quality roughage, whereas C was fed normal roughage. In the last 3 months, both groups were fed low-quality roughage. Dry matter intake (DMI) was determined at the 1st, 3rd, 5th and 7th months (P1, P2, P3 and P4). Analysis of liver tissue metabolomics were carried out in P2 and P3. Results DMI was greater in LR than C in P1 ( p < 0.05), but did not differ in P2. In P3 and P4, DMI was greater in LR than in C ( p < 0.01). The concentration of five glycolysis/gluconeogenesis intermediates, some lipid metabolism-related metabolites, six amino acids and several amino acid metabolism-related metabolites were different between treatments in P2. From P2 to P3, concentrations of these metabolites changed in LR. However, no difference was found between treatments in P3. Conclusion Feeding low-quality roughage to lambs early in life influenced hepatic glycolysis/gluconeogenesis, fatty acid oxidation and amino acid metabolism. However, for lambs who had no early experience with low-quality roughage, similar alterations were induced in the liver after 1 month of eating low-quality roughage.