The cholesterol content of eggs produced by Australian egg-laying strains

1. Eggs laid by the various strains entered in the 25th New South Wales Random Sample Layer Test were analysed for cholesterol content when the hens were 30, 45 and 60 weeks of age. 2. The strains differed in cholesterol content per gram of yolk and per egg. However most of the variation in cholesterol content per egg was attributable to strain differences in egg weight and in the proportion of yolk per egg. 3. Since 1 g of yolk contains approximately 6.7 times more energy and requires approximately four times the deposition energy of 1 g of albumen, the relation between the proportion of yolk within an egg and efficiency of egg production from food was considered. 4. It is recommended that comparisons of egg-laying strains and investigations into the efficiency of egg production from food should include an estimate of the proportion of yolk in the eggs.