Relative importance of reproductive traits on lifetime milk

Relationship of reprodustive traits (age and waight at first calving and days open percent) with life time milk yield and profit for 1380 Holstein X Sahiwal crossbreed cattle maintained at six military farms locatcd in Northern India was studied by the third degree polynomial Yegresson analysis and R². Age at first calving, weight at first calving and day open per cent accounted for 4.99, 2.05 and 19.64% of variation in life time milk yield, and 5.66, 9.87 and 15.92% variation in lifetime profit suggesting that the days open percent of the cows was more important than age at first calving and weight at first calving for milk yield as well as profit.