Repeatability (r) and heritability (h²) for reproductive traits were estimated from three meat-type chicken populations. One hundred and fifteen females were inseminated with semen of 23 males from three populations under a hierarchical mating system in a first experiment (E1) and with other 23 males in a second experiment (E2). Four hatches, or blocks, were produced for each experiment. Estimates of r and h² were obtained by analyses of variance among males, and among females within males within populations and experiments, performed with averages per hen in each hatch. Repeatabilities for egg production (POST) were significant (P<0.01) and equal to 0.19±0.05 and 0.32±0.04 in experiments E1 and E2 respectively. For hatchability of fertile eggs (ECLOD), the h² estimated from male components were 0.14±0.14 (P>0.05) and 0.26±0.17 (P<0.05). For hatchability of all eggs set (NASC), the h² (P<0.05) based on male components were equal to 0.18±0.15 (E1) and 0.26±0.17 (E2). The h² estimated from dam components were larger and significant (P<0.01). The dam estimates for ECLOD were 0.77±0.09 and 0.48±0.20 for E1 and E2 respectively, and for NASC, 0.58±0.21 (E1) and 0.48±0.20 (E2). The results confirm that ECLOD and NASC tend to present low additive genetic variability.
broilers; genetic parameters; reproduction rate
