Effect of dietary karaya saponin on serum and egg yolk cholesterol in laying hens.

摘要

Effects of dietary karaya saponin were investigated upon cholesterol deposition in laying chickens. 40 Boris Brown chickens were randomly assigned at 20 wk of age to 4 treatment groups and fed on diets supplemented with 0 (control), 25, 50 or 75 mg/kg karaya saponin for an 8 wk experimental period. After 8 wks of dietary supplementation, karaya-saponin-treated groups had significantly lower serum cholesterol (23.0%) and triglycerides, but higher HDL cholesterol concn. than controls, irrespective of karaya saponin content in the diet. Egg yolk cholesterol and triglycerides were also significantly reduced by dietary karaya saponin. Hepatic cholesterol and triglycerides were significantly reduced by karaya saponin, but bile acids concn. in the faeces and liver were significantly increased by karaya saponin. The concn. of oleic, linoleic and linolenic acids in the yolk were greater in chickens receiving karaya saponin than in controls. Karaya saponin significantly increased egg production, feed efficiency and yolk colour compared with controls. It also tended to increase egg wt., feed consumption, Haugh units, egg white wt. and yolk index. It is concluded that karaya saponin may be useful for reducing egg yolk cholesterol concn., increasing overall production performance and improving egg quality.