Total lipid and triacylglycerol contents in the liver of broiler and layer chickens at embryonic stages and hatching

To compare the hepatic function of broiler and layer chickens (Gallus gallus domesticus) at various embryonic stages and hatching, the total lipid and triacylglycerol (TG) content were determined. The chicken embryos accumulated a large amount of lipids in the liver and the total lipid content gradually increased toward hatching, though no significant difference was observed between broilers and layers. The TG contents in the liver increased considerably with developmental stage. At embryonic day 14 the TG content in the liver was similar between broilers and layers; thereafter, it was 1.3 and 2.2 times higher in broilers than in layers at embryonic day 18 and for newly hatched chicks, respectively. Chick embryos accumulate an excessive amount of cholesterol ester in the liver, but cholesterol ester is replaced by TG after hatching. The results of hepatic TG contents in the present study suggest that the development of the hepatic function between broilers and layers may already differ at embryonic stages.