Abstract
The effect of dietary lipid factors (plant and animal oil, cholesterol and ${\beta}$-sitosterol) on the liver, serum, and egg yolk cholesterol levels of the laying hen was studied. Single Comb White Leghorn laying hens, at 28 weeks of age, were fed two basal diets containing 8.0% soybean oil or 8.0% fish oil, with or without supplemental cholesterol (1.0%), ${\beta}$-sitosterol (2.0%) or combinations of both. Restricting caloric intake resulted in significantly (p<.05) decreased egg production and the total amount of cholesterol excreted via the egg was significantly (p<.05) different among treatment groups. Cholesterol supplementation to the two basal diets resulted in a significant elevation of liver, serum and egg yolk cholesterol levels. The addition of ${\beta}$-sitosterol lowered the cholesterol levels in liver and serum, while increased in the egg yolk (SO + ST, FO + ST). The anticholesterogenic effect of dietary ${\beta}$-sitosterol was not clearly exhibited in this study.