This study aims to estimate heritabilities, genetic correlations, and phenotypic correlations among first lactation milk yield and various reproductive traits in Hardhenu cattle. Records pertaining to first latation of 341 cows, the progeny of 51 sires; calved during the year 1995-2018, maintained at Cattle breeding farm, LUVAS, Hisar are analysed by using mixed model of Harvey. The reproductive traits considered include service period, dry period, first calving interval, number of inseminations for first successful conception, and number of inseminations for second successful conception. FLMY had a moderate heritability while SP, FCI, NIF and NIS had high heritabilities.

The results provide insight into the genetic and phenotypic relationships between milk production and reproductive performance, which are crucial for informed breeding strategies.