Eggs are a raw food material containing all substances indispensable for the development of young organism. They are used in the food industry, as well as in the pharmaceutical, cosmetic, chemical, and feed industry owing to the content of biologically active substances, among other things, immunoglobulin (IgY), phosvitin, and phospholipids. In the research covered by this paper, it was attempted to fraction chicken egg yolk in order to receive fractions containing rich amounts of immunoglobulin (IgY) and phosvitin, and, also, to isolate phospholipids. The raw material constituted fresh eggs laid by Lohmann Brown hens received from a specialist farm managed by the „Tronina” company. The layers were held in two groups and fed ad libitum. The control group of layers received a standard, full-portion feed mix and a preparation called Biostrong 510 (commercial name), which was a mixture of essential oils and high-quality herbal extracts in the encapsulated form. In the experimental group, the feed was supplemented with Humokarbowit and Humobentofet preparations (containing omega-3 acids) mixed at a mass ratio of 1 : 2. The content of IgY in the egg plasma of the control group remained at a level of approximately 3.6 mg / ml, while the plasma isolated from the enriched egg yolk laid by the hens fed a supplemented feed contained about 1 mg / ml more of protein. The content of phosvitin in egg yolk of the eggs laid by the layers fed the standard and enriched feed amounted to about 4%. The total protein content in the phosvitin fraction was at a similar level of approximately 60 %. The pure phospholipid fraction, extracted from the egg yolk of hens fed two types of feed and defined as the amount of a substance insoluble in acetone, was roughly 85%. The content of phosphatidylcholine (PC) in this fraction was about 75 %, and of phosphatidylethanolamine (PE) – approximately 24 %.