应用随机回归模型分析蛋鸡蛋黄质量遗传参数

[目的]以随机回归模型分析绿壳蛋鸡-白来航鸡资源群体蛋黄质量遗传规律和遗传参数。[方法]收集2011―2014年资源群体2 260只鸡生产记录,整理后获得11 759条蛋黄质量记录,用随机回归模型将Legendre多项式嵌入加性遗传效应、永久环境效应以及固定效应,各周龄以不同的残差效应处理。加性遗传与永久环境效应分别以1~3阶Legendre多项式评估,以AIC、BIC值以及残差值选择最优模型。利用WOMBAT软件以平均信息约束最大似然法(AIREML)分析表型方差组分。[结果]蛋黄质量遗传力为0.43~0.49,重复力为0.61~0.71;蛋黄质量加性遗传方差应嵌入3阶Legendre多项式,永久环境方差应嵌入2阶Legendre多项式;随机误差最低值出现在40周龄,最高值出现在56周龄;加性遗传方差随周龄增加而增加;各周龄之间遗传方差高度相关。[结论]随机回归模型适用于蛋黄质量遗传参数估算;蛋黄质量属于中等遗传力性状。
[Objectives]The goal of the present study was to analysis genetic development and parameters for yolk weight in the resource population with random regression model(RRM). [Methods]The data were collected from resource population for sequenced three generations from 2011 to 2014. A total of 11 759 yolk weights corresponding to 2 260 hens were evaluated. With RRM,several Legendre polynomials were embedded to estimate the fixed,direct genetic and permanent environment effects. The residual was grouped into 6 variance levels for each test week. 1-3 order polynomials were used to evaluate the direct additive genetic,permanent environment effects. Models were compared using AIC,BIC and residual values.(Co)variance components were estimated using AIREML method with WOMBAT software. [Results]The heritability of yolk weights ranged from 0.43 to 0.49. The repeatability laid in between 0.61 and 0.71. The direct genetic variance of yolk weight should be embedded with 3 order Legendre polynomials,and permanent environment with 2 order. Maximum error arose in 40 weeks,minimum error in 56 weeks. The direct genetic variance increased with the age. The estimate of genetic correlations between weeks was high above 0.86. [Conclusions]Random regression model should be an effective method for estimation on the yolk weights. Yolk weights belonged to the median heritability trait