Weighting Components of Type in Classifying Holstein

Abstract

In final scores of type from classifying 12,890 Holstein cows in 96 herds in Michigan, 1963 to 1966, the official classifiers underemphasized dairy character and body capacity and correspondingly weighted general appearance and mammary system excessively in relation to weights specified by the Dairy Cow Unified Score Card. In weighting designed to emphasize each component of type appropriately to make as large as possible the correlation between final score and milk produced in the lactation contemporary with the scoring, dairy character should receive most of the attention. For practical purposes dairy character could be the only component of type used since all others added scarcely any information. However, precisely what ratings of dairy character include and what the score card intends to do may introduce reservations about how influential dairy character should be.