Least-squares constants, heritabilities, genetic and phenotypic correlations among 300 days milk yield (MY300), total lactation milk yield (FLMY), lactation length (FLL) and dry period (FDP) were estimated using Henderson's method 3 from first lactation, records of 248 progeny of 25 Hariana bulls fitting a model with period and season of calving as fixed effects and sire within groups as a random effect with age at first calving as a linear covariate. Least-squares means of MY300, FLMY, FLL and FDP were 1103.02 ± 39.83 kg, 1351.35 ± 71.39 kg, 357.96 ± 13.68 days and 229.19 ± 9.94 days, respectively. The corresponding heritabilities were estimated as 0.364 ± 0.206, 0.471 ± 0.224, 0.442 ± 0.219 and zero. Genetic correlations among the MY300, FLMY and FLL were positive and significant. The phenotypic correlations of FDP with other traits were negative and highly significant.
