General and Specific Combining Ability for 154-Day Weight among Three-Line Crosses in Swine

Differences in the general combining abilities and the general maternal effects were estimated from 2137 three-line cross pigs of 12 Poland China inbred lines. Differences in general combining ability were statistically significant, accounting for 4% of the variation among pigs of the same season-farm group. Maternal effects of the lines and the interactions involving specific effects were not statistically significant. There was good agreement between the direct transmitting abilities of the lines when estimated from the three-line cross data and when estimated for five of the lines in farm herds where they were used for commercial production.