Heritability and genetic correlations of monthly egg production under random regression models were estimated. Three layer lines (A22, A88, K66) in six consecutive generations were analysed. A22 (13, 770 recorded hens) and A88 (13, 950 recorded hens) are maternal lines of Rhode Island White birds selected on egg production and shell colour; K66 (9, 351 recorded birds) is a paternal line of Rhode Island Red birds selected on egg weight. Eight models with different orders of Legendre polynomials were applied. Adequacy of the models was checked by the Akaike Information Criterion. According to the most adequate model including second order Legendre polynomials for fixed effects and third order for additive genetic and permanent environmental effects, relatively high heritabilities were estimated in the first (h²=0.3) and final (h² above 0.3) periods of production with a substantial decrease in heritability during the egg production peak. Methodology based on random regression animal models can be recommended for genetic evaluation of laying hens.

中文翻译：

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基于随机回归模型的蛋鸡月产蛋量遗传参数估计。

估计随机回归模型下月产蛋量的遗传力和遗传相关性。分析了连续六代的三层系（A22、A88、K66）。A22 (13, 770 只记录母鸡) 和 A88 (13, 950 只记录母鸡) 是根据产蛋量和壳颜色选择的罗德岛白鸟的母系；K66 (9, 351 只记录的鸟) 是罗德岛红鸟的父系，根据蛋重选择。应用了具有不同阶勒让德多项式的八个模型。模型的充分性由 Akaike 信息标准检查。根据包括固定效应二阶勒让德多项式和加性遗传和永久环境效应三阶的最合适的模型，在第一阶段估计了相对较高的遗传力（h ²=0.3) 和最后（h ²大于 0.3）时期，在产蛋高峰期间遗传力显着下降。可以推荐基于随机回归动物模型的方法对蛋鸡进行遗传评估。