Effects of α-lipoic Acid on Serum Fat Metabolic Parameters and Liver Enzyme Activities in the Transition Cow

Objective The effects of α-lipoic acid on serum fat metabolic parameters and liver enzyme activities in the transition cow were studied in an experiment. Method Forty-eight Holstein dairy cows at 20 d before calving were divided into four groups. Group Ⅰwas used as control. Group Ⅱto Ⅳ were fed with α-lipoic acid (3, 5 or 8 g·d-1) for 50 days. Blood samples were collected before the beginning of supplementation and at intervals of 10 days after supplementation. The following parameters indicative of fat metabolism and liver enzyme activities were measured in serum: triglyceride (TG), cholesterol (Chol), nonesterified fatty acid (NEFA), high-density lipoprotein (HDL), low-density lipoprotein (LDL) and alkaline phosphatase (AKP), γ-glutamyl transferase (γ-GT), lactate dehydrogenase (LDH), alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Result Serum fat metabolic parameters showed a declining trend by α-lipoic acid treatment, but only serum NEFA concentrations were significantly changed on day 30 in group Ⅳ as compared with control group (P0.05). Serum AST activities were significantly lower on day 30 in groups Ⅱ, Ⅲ and Ⅳ than in control group (P0.05 or P0.01). There were no significant differences in other parameters between the treatment groups and the control. Conclusion It is concluded that α-lipoic acid supplementation can improve fat metabolism and protect liver function in the transition cow.