The purpose of this experiment was to investigate the effects of breeder flock age (30 vs. 39 weeks) and sex of the newly hatched chicks on lipoprotein composition and apolipoprotein AI (apoAI) and B (apoB) concentrations. Additionally, fast protein liquid chromatography (FPLC) was used to evaluate which lipoprotein fraction (VLDL vs. LDL vs. HDL) carried the bulk of cholesterol in newly hatched chicks. Other lipoproteins were separated by density gradient ultracentrifugation to determine their chemical composition. Serum apoAI and apoB were compared by density scanning of VLDL, IDL, LDL and HDL fractions from sequential ultracentrifugation spins. The lipoprotein profile and apolipoprotein concentrations were similar for all chicks, so samples were pooled across both sexes and age groups to strengthen the data. For the lipoproteins, VLDL had the highest level of triglycerides followed by IDL, whereas the LDL particles had the highest levels of cholesterol esters compared to all other fractions. After separating the lipoprotein particles by size (FPLC) it was determined that both LDL and HDL carried approximately equal levels of cholesterol. These data suggest that lipoproteins in newly hatched chicks are not effected by sex or flock age chosen. In addition, LDL and HDL cholesterol are carried equally in newly hatched chicks.