Influence of Diet Composition on Hepatic Lipid Deposition in Two Lines of Australorps Selected for Liver Fat Differences

Abstract

This investigation was conducted to determine if the level of liver fat in Black Australorp laying hens, which had been selected over several generations for high or low liver fat content, would respond to changes in diet composition similar to the response of commercial strains of White Leghorns. In the first experiment, the two selected lines were fed either a corn-soybean diet (CS) or an tsonitrogenous and isoenergetic diet containing 4.89% each of fish meal, alfalfa meal, and torula yeast (FAY) for 6 weeks. Liver lipid was significantly higher for the high (19.4%) than for the low line (10.8%), but the FAY diet did not significantly affect this parameter. In a second 6-week experiment, the high and low lines of Black Australorps and unselected commercial White Leghorn hens were fed either the CS diet or one containing 14.67% distillers dried grains with solubles (DDGS). The DDGS significantly reduced both liver lipid and relative liver weight in Leghorns but not in the low and high liver fat Black Australorp lines. These results indicate that the mechanism of hepatic lipid accumulation in the genetically selected birds is different from that caused by feeding Leghorn hens a simplified CS diet and that the high liver fat line would not be useful in delineating nutritional effects on hepatic lipid accumulation.