Genetic parameters estimation on swine reproductive traits

[摘要] - With the objective to estimate genetic and phenotypic parameters of swine reproductive traits, litter weight at birth (PLN), litter weight at 21 days (PL21), litter size at birth (TLN), litter size at weaning (TLD) and mortality rate (TM) data of three swine breeds, Duroc, Landrace and Large White were used. The genetic and phenotypic (co)variances were estimated by Restricted Maximum Likelihood (REML) method. These components were used to estimate the direct (), maternal () and total () heritabilities, the common litter effect (c2), and the genetic and phenotypic correlations. The direct, maternal and total heritability estimates were small to medium, 0.00 to 0.17, 0.00 to 0.14 and 0.00 to 0.15, respectively, indicating the necessity to include information on relatives in selection programs to improve these traits. The correlations among the additive direct and maternal genetic effects were, in general, high and negative, evidencing antagonism among these effects. The estimates of c2 were, in general, low, for all traits and breeds. The genetic correlations among PLN, PL21, TLN and TLD tended to be high and positive, and the correlations between these traits and TM were positive in some cases, and negative in others.

[学科分类] 兽医学

[关键词] animal model;litter;maternal effects;REML;swine    IntroduçãoO conhecimento das propriedades genéticas das populações baseia-se em parâmetros genéticos que podem ser obtidos utilizando-se componentes de variância;que podem ser estimados por vários métodos