Single and Multiple Trait Sire Selection. First Lactation Milk Yield and Composition, Conformation, Feed Intake, Efficiency, and Net Income

Abstract

Difference milk of first lactations (yield) were compared with daughters of sires selected on an udder index from among artificial insemination bulls with less than 10% of their daughters culled and with a Predicted Difference fat-corrected milk greater than 181 kg (merit). On latest proofs yield bulls were 425 kg higher than merit bulls for Predicted Differences of first lactations, whereas merit bulls had an average Predicted Difference Type, which was 1 point higher than yield bulls. Data were from first calving interval.