Genetic parameter estimates of growth traits of indigenous pigs in Northern Ghana

MTDFREML procedures were used to estimate heritabilities and genetic correlations for some growth traits using records of 1044 indigenous Ghanaian pigs. Growth traits analysed were birth weight (BW), pre-weaning average daily gain (ADG 1), weaning weight (WW), post-weaning average daily gain (ADG 2) and 180 day weight. Animal models employed had year of birth, season of birth, sex of piglet, parity of sow and litter size at birth as fixed effects and additive genetic value of animal, maternal genetic value of dam and permanent environmental effect of dam as random effects. Direct heritability for BW, ADG 1, WW, ADG 2 and 180 day weight was 0.06 ± 0.01, 0.21 ± 0.08, 0.14 ± 0.04, 0.22 ± 0.80 and 0.08 ± 0.69 respectively while corresponding maternal heritabilities were 0.75 ± 0.01, 0.24 ± 0.08, 0.57 ± 0.07, 0.63 ± 1.28 and 0.32 ± 1.03 respectively. Maternal heritabilities were therefore higher than direct heritabilities for growth traits. Genetic correlations found in this study among growth traits indicate that selection to improve one trait would be associated with favourable changes in the other traits.