INFLUENCE OF DIETARY MENHADEN OIL ON GROWTH RATE AND TISSUE FATTY ACIDS OF THE CHICK.

Using purified diets containing 2 sources of protein, an essential fatty acid deficiency was produced in chicks that was characterized by poor growth and a high quantity of eicosatrienoic acid in the liver lipid. The feeding of corn oil caused an increase in the eicosatetraenoic acid and a decrease in the eicosatrienoic acid content of the liver. The feeding of menhaden oil did not change the eicosate traenoic acid content of the liver lipid, but caused a complete disappearance of eicosatrienoic acid. Eicosapentaenoic acid, docosapentaenoic acid and docosahexaenoic acid were present in the liver only when menhaden oil was fed. The data indicate that the feeding of fish oil with its high content of long-chain polyunsaturated fatty acids inhibits the synthesis of eicosatrienoic acid in the chicken. When menhaden ou was fed with corn oil, the level of arachidonic acid present in the liver and heart fat was decreased from levels resulting when corn oil is fed alone. Some interpreta tions of these observations are discussed. Marine oils contain large amounts of long-chain polyunsaturated fatty acids