Abstract
The age and weight at first calving averaged 1236.58 days and 353.95 kg, respectively. Average first lactation 305-day milk yield and milk yield per day of lactation were 1896.03 and 6.53 kg, respectively, The pospartum oestrus interval, service period and number of services per conception averaged 160.04 days, 216.86 days and 2.13 days, respectively. The correlation and regression analysis revealed that age at first calving had non-significant effect on all parameters studied. the correlation and regression coefficient between age and weight at first calving were 0.052 and 0.012, respectively. The correlation coefficient between age at first calving and first lactation 305-day milk yield, yield per day of lactation, postpartum oestrus interval, service period and number of services per conception were 0.018, 0.038, - 0.105,0.087 and 0.051,respectively
