Estimates of (co)variance components and genetic parameters for growth traits in Suffolk lambs

Ciência Rural

Tamioso, Priscilla Regina¹  Teixeira, Rodrigo de Almeida²  Alberti Filho, Jaime Luiz²  Dias, Laila Talarico² 

[1] Universidade Federal do Paraná (UFPR), Curitiba, Brasil;UFPR, Curitiba, Brasil

关键词: average daily weight gain;    body weight;    heritability;    maternal effects;    Suffolk;   

DOI  :  10.1590/S0103-84782013001200016

学科分类：农业科学（综合）

来源: Universidade Federal de Santa Maria * Centro de Ciencias Rurais

【 摘 要 】

The study aimed to estimate the components of (co)variance and heritability for weights at birth (BW), weaning (WW) and 180 days of age (W180), as well as the average daily gains from birth to weaning (ADG1), birth to 180 days of age (ADG2) and weaning to 180 days of age (ADG3) in Suffolk sheep. Thus, three different single-trait animal models were fitted, considering the direct additive genetic effect (Model 1), the direct additive genetic and maternal permanent environmental effects (Model 2), and in Model 3, in addition to those in Model 2, the maternal additive genetic effect was included. After comparing models through the likelihood ratio test (LRT), model 3 was chosen as the most appropriate to estimate heritability for BW, WW and ADG1. Model 2 was considered as the best to estimate the coefficient of heritability for W180 and ADG2, and model 1 for ADG3. Direct heritability estimates were inflated when maternal effects were ignored. According to the most suitable models, the heritability estimates for BW, WW, W180, ADG1, ADG2 and ADG3 were 0.06, 0.08, 0.09, 0.07, 0.08 and 0.07, respectively, indicating low possibility of genetic gain through individual selection. The results show the importance of including maternal effects in the models to properly estimate genetic parameters even at post-weaning ages.

【 授权许可】

CC BY-NC