Nicotinamide supplementation during postpartum and peripartum modulates hepatic energy and lipid metabolism, oxidative status, and metabolomics profile, as well as lipids in the adipose tissue of goats

•Nicotinamide supplementation favored the rumen fermentation pattern to propionic acid-type.•Nicotinamide supplementation improved the hepatic mitochondrial respiratory chain to generate ATP.•Nicotinamide works effective in postpartum while only is not enough to cope with metabolites of oxidative phosphorylation.•Nicotinamide supplemented from prepartum is needed for better oxidative status and energy metabolism of peripartum does. Dairy ruminants are often in negative energy balance, primarily in the postpartum period, resulting in many metabolic disorders and economic losses. Improving energy efficiency during the peripartum period is urgently important. It has been previously highlighted that nicotinamide (NAM) supplementation during the peripartum period could benefit energy balance, while the underlying metabolic alterations and differences between postpartum NAM supplementation and peripartum NAM supplementation have not been extensively studied. This study attempted to elucidate the effects of NAM supplementation during the postpartum and peripartum periods on rumen fermentation, liver mitochondrial respiratory chain status, lipid metabolism, oxidative status, and liver metabolite profile of does. Fifteen multiparous does with similarity were paired and allocated to 3 groups (n = 5): control (C, no NAM supplementation), postpartum supplementation (P, NAM supplemented from d 1 to 28 after kidding), and entire-peripartum supplementation (EP, NAM supplemented from d -2 1 to 28 around kidding). Does were drenched with NAM at 5 g/d and subsequently slaughtered on d 28. The ruminal proportion of acetic acid tended to decrease, and propionic acid and valeric acid were increased in P and EP. The does in P and EP had a decreased acetic acid to propionic acid ratio. Does in EP had higher liver mitochondrial respiratory chain complexes. The activity of liver complex Ⅱ was elevated in P and EP, and NAM supplementation tended to increase ATP production. Liver metabolomics and tissue biochemical analyses demonstrated that TG synthesis was decreased in abdominal adipose tissue by NAM supplementation. In the liver, the decomposition and synthesis of TG were both promoted, and amino acid metabolism was enriched by NAM supplementation. Moreover, the oxidative status of the blood and liver was improved by NAM supplementation, and NAM supplementation during the postpartum period was more effective but did not appear to be sufficient to cope with the metabolites of oxid