Fatty acid composition of liver lipids during ontogeny of the chick embryo: effect of a single dose of triiodothyronine.

Abstract

Fatty acid composition of chick liver was determined throughout embryo development. Fourteen, seventeen and twenty day old chick embryos as well as newborn chicks were studied. Chromatograms show that in all cases the same fatty acids were presented, even when lipid fractions such as phospholipids, cholesterol and triacylglycerol were studied separately. The lack of poly-unsaturated fatty acids is in contrast with the results obtained in previous investigations on rats. A slight increase in the unsaturated/saturated fatty acid ratio as the embryo grew older was observed. The effect of a single dose of 3-3'-5-Triiodothyronine (T3) on composition of fatty acids throughout the embryonary period was also studied. The hormone only affects fatty acid levels in the 20th and 21st days of incubation.