Bennewitz J, Morgades O, Preisinger R, Thaller G, Kalm E
Institut für Tierzucht und Tierhaltung, Christian-Albrechts-Universität, D-24098 Kiel, Germany.
Poult Sci. 2007 May;86(5):823-8. doi: 10.1093/ps/86.5.823.
Variance components and breeding values were estimated for 3 reproductive traits in a pure line of White Leghorn laying hens. The traits were proportion of fertile eggs of eggs set, proportion of first quality chicks of eggs set, and proportion of first-quality chicks of fertile eggs. A total of 3,020 hens were tested up to 3 times over a period of 7 d. For the definition of the traits, each egg was scored for each trait either as 0 or 1. To account for the binomial distribution of the data, a Bayesian animal threshold model implemented in a Gibbs sampler was applied that considered the record of each egg set as a repeated observation of the hen. The estimated heritability was 0.067, 0.126, and 0.136 for the traits proportion of fertile eggs of eggs set, proportion of first quality chicks of eggs set, and proportion of first-quality chicks of fertile eggs, respectively, and the SE were small. It was shown that the heritability estimates were substantially higher from their expected values based on linear models. This results in a higher genetic progress and consequently favors the applied Bayesian threshold model for a genetic evaluation of binomial distributed reproductive traits.
对白来航蛋鸡纯系的3个繁殖性状估计了方差组分和育种值。这些性状分别是入孵蛋的受精蛋比例、入孵蛋的一级雏鸡比例以及受精蛋的一级雏鸡比例。在7天的时间里，共对3020只母鸡进行了多达3次的测试。为了定义这些性状，每个蛋的每个性状都被记为0或1。为了考虑数据的二项分布，应用了在吉布斯采样器中实现的贝叶斯动物阈模型，该模型将每个入孵蛋的记录视为对母鸡的重复观测。入孵蛋的受精蛋比例、入孵蛋的一级雏鸡比例以及受精蛋的一级雏鸡比例这三个性状的估计遗传力分别为0.067、0.126和0.136，标准误较小。结果表明，基于线性模型，遗传力估计值显著高于预期值。这导致了更高的遗传进展，因此有利于应用贝叶斯阈模型对二项分布的繁殖性状进行遗传评估。
