Data on feed gain ratio, age at 100kg, backfat thickness adjusted for 100kg and average daily weight gain were used to estimate genetic and phenotypic parameter for performance traits of Large White breed. Analyses were carried out separately by sex as a result of different management systems. Variance, genetic and phenotypic covariances were estimated by Restricted Maximum Likelihood method, including in the model the direct genetic effects, maternal effects and common litter effects. Estimates of heritabilities for the direct genetic effects ranged from 0.13 to 0.55, suggesting direct selection response for these traits. The estimates for the maternal effect were low and ranged from 0.02 to 0.05. The genetic correlations between traits indicated that selection program to improve all traits should be based on direct selection to improve age at 100 kg, feed gain ratio and backfat thickness. Genetic gains on average daily gain should be based on indirect selection for age at 100kg.
swine; daily gain; backfat thickness; feed:gain ratio; genetic correlation; heritability
