Records of 24,703Nelore cattle from six herds were used to estimate coefficients of heritabilityfor probability of pregnancy at 14 months (PP14) and hip height (HH) traits.For PP14, the mathematical model included as fixed effects the contemporarygroups (181 groups) and dam age class at calving (7 classes) and for HH onlycontemporary groups (584 groups). Random effects included were genetic additiveof sire and residual effects. Variance and covariance components were obtainedby method Â. Heritability estimates were 0.73± 0.01 and 0.30 ± 0.00 for PP14 and HH, respectively. Genetic correlationestimate between PP14 and HH was 0.10 ± 0.01. Results reveal that PP14is of high heritability and, therefore, it can be indicated for selection programsof bulls with the objective of increasing the heifer fertility. The value ofthe genetic correlation suggests low genetic correlation between the two traits,indicating that selection for growth, measured by the HH, is not a so strongantagonism to the precocity of the heifers measured by PP14.
