Department of Animal Genetics and Breeding, Chandra Shekhar Azad University of Agriculture and Technology, Mathura Campus, Mathura - 281001, India.
*Part of MVSc. thesis, Senior author.
The records of 805 Sahiwal cows progeny of 48 sires, the estimation of least square means for WFC (weight at first calving), AFC (age at first calving), FLPY (first lactation peak yield), F300 (first lactation 300 days milk yield), and FCI (first calving interval) were 314.13±2.44 kg, 1188.79±15.95 days, 8.82±0.18 kg, 1511.06±29.42 kg, 492.76±8.18 days, respectively. The least square analysis of variance revealed the significant effect of season of calving on WFC (P<0.05), AFC FLPY, and F300 (P<0.01) and period of calving on AFC (P<0.01), WFC, and FLPY (P<0.05). The heritability was low for FCI, medium to moderate for FLPY and F300. Heritability for WFC revealed no genetic variation but for AFC revealed adequate genetic variation for improvement of the trait. The results of genetic and phenotypic correlation between different economic traits suggested that in future selection programme a negative pressure should be given to AFC while selecting these cows on the basis of milk yield traits.
