二世代母鸡血浆VLDL浓度双向选择对蛋组成性状的影响

以雅发褐壳蛋鸡为素材，在一世代双向选择的基础上，依据血浆极低密度脂蛋白(VLDL)浓度对腹脂性状继续进行双向选择，比较高、低脂系蛋组成性状之间的差异，并研究二世代母鸡中、后期血浆VLDL浓度与蛋组成性状的相关程度。结果表明：二世代双向选择系母鸡间40周龄蛋黄重、蛋黄蛋白比例及60周龄蛋黄蛋白比例差异显著。血浆VLDL浓度与高、低脂系的蛋黄重、蛋黄比例、蛋黄蛋白比例呈显著正表型相关和中等程度正遗传相关，说明依据血浆VLDL浓度的低向选择可使蛋黄重、蛋黄比例、蛋黄蛋白比例降低。

Effect of Plasma Very Low Density Lipoprotein Concentration Divergently Selecting on Egg Composition of Layer Chickens

On the basis of the 1st generation, abdominal fat of Yafa brown layers were divergently selected by using plasma very low density lipoprotein (VLDL) concentration. The difference of egg composition between high and low fat lines was compared, the genetic and phenotypic correlation between plasma VLDL and egg composition was also estimated. The results showed that yolk weight, yolk to egg weight ratio and yolk to albumen ratio at 40 or 60 weeks old in high fat line were significantly higher than that of the low fat line, and the significant positive phenotypic correlation and positive moderate genetic correlation between plasma VLDL concentration and yolk weight, yolk to egg weight ratio and yolk to albumen ratio were found, which indicated that yolk weight, yolk to egg weight ratio and yolk to albumen ratio would be reduced with selection for lower plasma VLDL concentrations.