Lifetime Production and Longevity of Cows Related to Their Sires’ Breeding Values

Abstract

Canadian Record of Performance data on 30,738 Holstein daughters of 138 sires from 1,498 herds across Canada were used to study relationships of breeding values of sires for early production with later performance and longevity of daughters. Expected breeding values were estimated by multiplying the regression of future daughters on present daughters with twice the least square estimate of effects of genetic group plus sire within genetic group. Though sires ranked differently for yield and longevity traits, there were positive relationships between expected breeding values for lifetime production and longevity. Sires with expected breeding values for first lactation milk more than 0kg or expected breeding values for first lactation fat more than 0kg had considerably higher expected breeding values for total lifetime yields and longevity. Correlations of expected breeding values for first lactation yields with lifetime production and with longevity ranged from .33 to .89. Expected breeding values for first lactation milk and fat yields were good predictors of expected breeding values for milk and fat yields per day of productive life. Differences between sires in their heifer progeny tests will be maintained in their daughters’ total lifetime production.