The influence of maternal effects on growth traits of Landrace pigs

This paper was aimed to study the influence of maternal effect on estimation of genetic parameters and breeding values for growth traits in Landrace pigs. Landrace W51-line pigs were used as materials. Three quantitative traits related with growth performances, birth weight, age to reach 30 and 100 kg were chosen. Two models including or ignoring maternal effect were used to estimate genetic parameters and breeding values. Results showed that the model including maternal effect was more reasonable to explain the growth traits. Heritability estimates were inflated obviously and estimated breeding values were deviated more seriously using the model ignoring maternal effect. With increasing ages, the proportion of maternal variances gradually decreased but directive additive genetic variances increased, indicating that the influence of maternal effect became smaller in the later growth stage of pigs. It is necessary to consider the influence of maternal effects on estimating genetic parameters and breeding values for building animal growth trait models.