AN EVALUATION OF THE LIPOPROTEIN COMPOSITION AND CORRESPONDING APOLIPOPROTEINS IN THE NEWLY-HATCHED MALE AND FEMALE BROILER CHICK FROM 2 DIFFERENT AGE FLOCKS

The purpose of this experiment was to investigate the effects of breed er flock age (30 vs, 39 weeks) and sex of the newly hatched chicks on lipoprotein composition and apolipoprotein Al (apoAI) and B (apoB) con centrations. Additionally, fast protein liquid chromatography (FPLC) w as used to evaluate which lipoprotein fraction (VLDL vs. LDL vs. HDL) carried the bulk of cholesterol in newly hatched chicks. Other lipopro teins were separated by density gradient ultracentrifugation to determ ine their chemical composition. Serum apoAI and apoB were compared by density scanning of VLDL, IDL, LDL and HDL fractions from sequential u ltracentrifugation spins, The lipoprotein profile and apolipoprotein c oncentrations were similar for all chicks, so samples were pooled acro ss both sexes and age groups to strengthen the data. For the lipoprote ins, VLDL had the highest level of triglycerides followed by IDL, wher eas the LDL particles had the highest levels of cholesterol esters com pared to all other fractions. After separating the lipoprotein particl es by size (FPLC) it was determined that both LDL and HDL carried appr oximately equal levels of cholesterol. These data suggest that lipopro teins in newly hatched chicks are not effected by sex or flock age cho sen. In addition, LDL and HDL cholesterol are carried equally in newly hatched chicks.