Results and Discussion
Effect of the dietary cholecalciferol level on the transfer of cholecalciferol to egg yolk
Cholecalciferol content of egg yolk from the control (diet 1)
was 119 ± 31 IU/100 g egg yolk (or 17.7 IU per egg), which was
almost unchanged during the entire experimental period. Chole- calciferol concentrations in the yolk from diet 2 to 5 increased rapidly during the first 3 wk, and then remained relatively sta- ble for another 5 wk. After 8-wk feeding, a gradual reduction of cholecalciferol concentrations in the yolks from diet 2 to 5 oc- curred and then reached a steady state at weeks 16 to 25 (Figure 1). Toward the end of hen laying cycle, the cholecalciferol