Laboratory model with chicks for assay of nutritional factors affecting hepatic lipid accumulation in laying hens.

A laboratory model with chicks is described that is suggested as an assay for dietary factors affecting liver lipid accumulation in laying hens. The model utilizes growing White Leghorn male chicks injected with estrogen. Diets to be tested were fed ad libitum for 4 days following 2 days starvation. Liver lipid deposition was increased with increasing level of estradiol injected. Lipid deposition in livers of estrogenized chicks fed a diet containing fish meal, alfalfa meal, and torula yeast (FAY) was significantly less than that in chicks fed a corn-soybean meal (CS) diet. This correlated with a similar response in laying hens fed ad libitum FAY and CS diets for 30 days, suggesting the response of livers to dietary changes in fasted-refed-estrogenized chicks reflects the responses obtained with laying hens. Using the proposed laboratory model, fish meal, distillers dried grains with solubles, and alfalfa meal were shown to contain activity that reduced liver lipid deposition.