Influence of Feeding Cottonseed Oil to Laying Hens on the Low Density Lipoproteins of their Eggs

Abstract
Low density lipoproteins, isolated from yolks of eggs produced by hens fed a normal diet and from those of hens fed 2.5% cottonseed oil in the diet, were studied to determine the effect of crude cottonseed oil on properties of the yolk lipoproteins. Low density lipoproteins isolated from eggs produced by hens fed crude cottonseed oil contained more saturated fatty acids and less monoenoic fatty acids than did those isolated from normal eggs. Differences in amino acid content of the vitellenins from normal and “cottonseed” eggs were small. When low density lipoproteins were separated into six fractions by ultracentrifugation, most of those from normal eggs were in the top four fractions, but most from the cottonseed oil eggs were in the bottom three fractions. Cottonseed oil low density lipoproteins were on the average larger in size than the normal ones as determined by gel filtration through a Bio-gel A-15m column. The floating fraction of normal low density lipoproteins isolated by ultracentrifugation contained more lipid and the molecules were larger than the soluble low density lipoproteins in the bottom fraction, and the lipoproteins in intermediate fractions were intermediate in lipid content and size of molecule. Cottonseed oil low density lipoproteins were also separated according to molecular size, but the different fractions were similar in lipid content.