The effect of adding cholesterol to laying hen diets as powder or predissolved in fat

An experiment was conducted to determine if adding supplemental cholesterol to the feed or first adding it to the supplemental fat source of laying hen diets would result in differences in egg yolk and liver cholesterol levels. Five levels of cholesterol (0, .5, 1, 2, and 4%) and three levels of animal tallow (0, 4, and 8%) were used. The diets were randomly assigned and fed for 35 days to individually caged hens within each of six replicates. Eggs laid on or near Days 0, 7, 14, 21, 28, and 35 were used for cholesterol analysis. Liver cholesterol, egg production, and feed intake were also assessed. Mixing cholesterol with the fat source before feed incorporation did not promote higher yolk or liver cholesterol levels and were essentially the same as the method in which powdered cholesterol was added directly to the feed. A linear increase in yolk and liver cholesterol was observed with 0, .5, and 1% dietary cholesterol. Yolk cholesterol also increased linearly during the first 14 days of cholesterol administration. Further increases in yolk cholesterol, however, were not obtained with either the higher levels of dietary cholesterol or the extended feeding times.