Two experiments were conducted to determine the effect of
dietary fiber in rations of varying nutrient density on egg yolk
cholesterol, energy balance and reproductive efficiency of laying hens. Initially, four diets arranged in a Latin square design were tested: low, medium and high nutrient density diets and a control diet. The energy-to-
protein ratio was 171.8 kcal/%
protein for all diets. Significant differences (P less than 0.01) were observed between diets for feed intake, feed efficiency and fecal output of the hens. Dietary differences in yolk
cholesterol, egg production, egg
weight, body weight change and energy balance were not significant, and hence unrelated to
dietary fiber level. A significant negative correlation (P less than 0.01) was found between yolk
cholesterol and egg production (r = -0.45) or egg energy output (r = -0.38). In addition, yolk
cholesterol was positively correlated with
body weight change (r = 0.23, P less than 0.01). In the second experiment, the possible relationship between level of feed intake,
body weight change and yolk
cholesterol was further investigated. Yolk
cholesterol tended to increase when the laying pullets consumed more than 387 kcal ME/day or gained more than 100 g in
body weight. When the energy intake was less than 340 kcal ME/day or the birds lost
body weight, an increase in yolk
cholesterol also was noted but was inversely related to feed intake or
body weight change.