Fatty acid composition of residual yolk and liver from broiler chicks hatching from omega-3 enriched eggs

Fatty acids in the diets of broiler breeder hens, such as arachidonic acid (AA, 20:4 n-6), eicosapentaenoic acid (EPA, 20:5 n-3) and docosahexaenoic acid (DHA, 22:6 n-3), can be built into the yolk and therefore be available to the progeny for their development (Noble et al., 1990). They are absorbed from the residual yolk and are built in the liver to serve as a reservoir for eicosanoid production, neural development,… (Speake, 1998). From 6 weeks on 480 Ross-308 broiler breeder hens were fed 4 different diets (control, EPA=DHA, DHA>EPA or EPA>DHA) . At 28 weeks of age, 60 fresh yolk were weight and 20 fresh yolks per treatment were pooled by 4 for FA analysis (n=5), the remaining eggs were incubated. After hatch, 12 livers per treatment were sampled at day 1, 14 and 30. At 38 weeks, eggs were incubated and 25 residual yolks were sampled per treatment, weighed and pooled by 5 for FA analysis (n=5). n-3 enriched eggs had a significantly lower fresh yolk and residual yolk weight. Eggs from EPA enriched hens had significantly more EPA in their fresh yolk and residual yolk, while the DHA content was increased in fresh and residual yolk in the eggs of all n-3 enriched hens. At d1 post hatch both the hepatic EPA and DHA concentration was significantly higher for offspring from enriched hens. Hepatic DHA content decreased with post hatch age, highlighting the role of DHA early in the development.