The effects of antioxidants on the content of polyunsaturated fatty acids in the hen's egg.

In experiments to see whether, in the possible interests of human health, the polyunsaturated fatty acid (PUFA) content of the chicken's egg can be increased by nutritional means, three strains of hen, light, medium, and heavy, each at the peak of lay, were first fed a basal, commercial, low-fat diet. The hens were then transferred to one of the following diets: basal + safflower oil (SO); basal + SO + butylated hydroxytoluene; or basal + SO + dl-a-toco-pheryl acetate. The diets were designated "Blank", "BHT", and "Vitamin E", respectively, the second and third containing the added antioxidants. The eggs produced were weighed, and their yolks weighed and analysed for lipid components. Additional of SO (7.5%) to the basal diet led to the PUFA content of the yolk lipids rising by 15.4% (linoleic acid, 14.1%), the magnitude of the increases being unaffected by the antioxidants. Diet "BHT" produced larger eggs and yolks than the other diets, but the proportion of yolk was the same on the three types of feed. The total cholesterol content of egg yolks was significantly affected neither by diet, nor by strain or age of hen. The implications of these results are discussed.