Talerngsak Angkuraseranee

pp. 115 - 117

Abstract

The additive and dominance genetic variances of 5,801 Duroc reproductive and growth records were estimated using
BULPF90 PC-PACK. Estimates were obtained for number born alive (NBA), birth weight (BW), number weaned (NW), and
weaning weight (WW). Data were analyzed using two mixed model equations. The first model included fixed effects and
random effects identifying inbreeding depression, additive gene effect and permanent environments effects. The second
model was similar to the first model, but included the dominance genotypic effect. Heritability estimates of NBA, BW, NW
and WW from the two models were 0.1558/0.1716, 0.1616/0.1737, 0.0372/0.0874 and 0.1584/0.1516 respectively. Proportions
of dominance effect to total phenotypic variance from the dominance model were 0.1024, 0.1625, 0.0470, and 0.1536 for NBA,
BW, NW and WW respectively. Dominance effects were found to have sizable influence on the litter size traits analyzed.
Therefore, genetic evaluation with the dominance model (Model 2) is found more appropriate than the animal model (Model 1).