The aim of this study was to investigate if the hen?s genotype, age and diet affect fat components in egg yolk. The fat components measured were total fat content, Phospholipids, cholesterol and the fatty acid profile. This trial involved 12 groups of laying hens housed in 8-hen cages enriched with perches, dust baths and nests. The genotype Lohmann Selected Leghorn (LSL) and the genotype Lohmann Brown (LB)was used.