Effect of ultra-fine traditional Chinese medicine compounds on regulation of lipid metabolism and reduction in egg cholesterol of laying hens

This study has the objective of investigating the effects of traditional Chinese medicine prescriptions (TCM) on serum lipid, abdominal and hepatic fat percentage, cholesterol content in eggs, and mRNA expression of genes apoA I and apoB₁₀₀. One hundred and thirty five healthy (300-day-old) layers were randomly assigned to three treatments. The hens in control group were fed with the basal diet. The hens in the experimental groups (TCM 1 and TCM 2) were fed with the basal diet supplemented with 1% TCM 1 and 1% TCM 2 respectively over a period of 60 days. Laying performance and the serum parameters relevant to fat metabolism were measured. The results showed that no significant differences were found in average daily feed intake and egg weight among three treatments. Average daily laying rate in TCM treatments was increased, and the cholesterol content in eggs was decreased. The serum triglyceride (TG), total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) levels in experimental treatments were decreased (p<0.05), while the serum high-density lipoprotein cholesterol (HDL-C) level was increased (p<0.05) compared to the control group. Additionally, abdominal fat percentage decreased in TCM 1 treatment (p<0.05), and hepatic fat percentage decreased in both TCM treatments (p<0.05). The expression of apolipoprotein A I (apoA I) and apolipoproteinB₁₀₀ (apoB₁₀₀) mRNA in the liver increased in both TCM treatments (p<0.05). These results suggest that the diet supplemented with TCM could increase the expression of apoA I and apoB₁₀₀ mRNA in the liver, and decrease lipid content in the serum, and reduce egg cholesterol in layers.