Brain lipids in rats fed a diet supplemented with hen eggs of modified lipid content

The aim of this study was to research the impact of a diet supplemented with egg yolks of modified content, having in mind the type of fat added to the laying hens diet, on the brain lipids and their fatty acid composition in rats. During four weeks of the experiment, 64 Wistar rats, divided into four groups of 16 animals each (eight animals of both sexes), were fed the commercial rat feed (group C), or the feed that contained 70% of the commercial rat feed and 30% of freshly boiled yolks from the eggs originating from laying hens fed with 3% fish oil (group F), 3% palm olein (group P) or 3% lard (group L). Concentration and content of total lipids and total cholesterol, as well as the fatty-acid composition of the total brain lipids were determined in the lipid extracts of the rats brains. Under unfavourable conditions, which in our case could be high dietary intake of the total fat due to egg yolk addition, the amount of total fat in the brain tissue or the mass of the organ itself can be changed. Applied dietary treatments could also influence the level of de novo synthesis of total cholesterol in the rat brain. High dietary fat intake, as well as the fat quality regarding its fatty acid composition, appear to be able to significantly influence the fatty acid profile of the total brain lipids in adult rats, whereas the level and quality of the changes also depend on sex