Economic values of traits for dairy cattle improvement estimated using field-recorded data

Abstract

The objective of this study was to compute economic values of traits using an empirical approach. The data set consisted of 193 257 lifetime records of Holstein and Ayrshire cows. Different profitability measurements were used as the dependent variables in covariance models to compute different sets of economic values. A kilogram genetic increase in fat production had economic values between $25 and $31 in Holstein herds and between $34 and $36 in Ayrshire herds using lifetime profit as the dependent variable. A unit genetic increase in conformation had the highest positive impact on profit ($176 in Holstein herds and $300 in Ayrshire herds) while a similar increase in capacity had a negative impact on profit (between $–30 and $–102 in Holstein herds and $–92 in Ayrshire herds). Using lifetime profit adjusted for the opportunity cost of postponed replacement reduced the influence of type traits on profit. Finally, profits of first lactations were used to study the consequences of changes in pricing systems that occurred in Quebec in August 1992. A kilogram genetic increase in protein production had negative economic values in the 1980s ($–3.70$ in Holstein herds and $–8.33 in Ayrshire herds) and positive economic values after August 1992 ($7.50 in Holstein herds and $12.83 in Ayrshire herds). Key words: Dairy cattle, economic value, field-recorded data, profitability, estimated breeding value