The effect of saikosaponin a on lipid metabolism in laying hens (n = 6). (A) The egg production rate and the feed intake. (B) The rate of abdominal fat and liver. (C) Serum total triglyceride (TG) and total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) levels. (D) Yolk TG and TC levels. (E) Liver TC, TG, and nonesterified fatty acid (NEFA) content. a,bDifferent letters represent significant differences (P < 0.05). CON, control group; HELP, high-energy and low-protein diet group; HELP + SSa, high-energy and low-protein with saikosaponin a group.