Preferential Accumulation of n-3 Fatty Acids in the Brain of Chicks from Eggs Enriched with n-3 Fatty Acids

Docosahexaenoic acid (DHA) is the major polyunsaturated fatty acid in the phospholipids of brain tissue. The extent to which maternal dietary n-3 fatty acid may influence the n-3 fatty acid composition of phosphatidylethanolamine (PE) and phosphatidylcholine (PC) fractions of brain and liver tissue of progeny was investigated. Hens were fed diets containing n-9, n-3, or n-6 fatty acids. The brain tissue of the chicks from eggs enriched with n-3 fatty acids contained higher DHA, resulting in an increased C22:6 n-3:C20:4 n-6 ratio compared with chicks from eggs enriched with n-9 or n-6 fatty acids. Incorporation of C22:5 n-3, and C22:6 n-3 was mainly in the PE fraction as compared with the PC fraction of the chick brain. For chicks hatched from eggs enriched with n-9, n-3, and n-6 fatty acids, the total n-3 fatty acids in the brain PE fraction were 29.3, 41.3, and 21.9% compared with 6.7, 8.8, and 4.0% in the brain PC fraction. In contrast, the n-3 fatty acids increased evenly in phospholipid PC and PE fractions. Total amounts of PE in the brain lipids of chicks from eggs enriched with n-3 and n-6 fatty acids were 40.8 and 41.9% compared with 33.1% for chicks from eggs enriched with n-9 fatty acids. Analyses of the remaining yolk sac revealed a preferential absorption of DHA from the egg PE fraction by the developing chick.