Abstract

The relative importance of the currently recorded large number of descriptive conformation traits and of milkfat yield on retention for a second lactation of 6645 Friesian-sired and 5709 Jersey-sired heifers was examined. In a linear multiple regression model, the effect of heifers deviating from the 'normal' conformation for a certain trait on the retention rate was used as an indicator for the relative importance of the trait. Milkfat yield was by far the most important trait for both breeds. Only a small number of conformation traits describing udder and teats influenced the retention rate significantly. The farmer with Jersey cows appeared to consider more conformation traits as important than the owner of Friesian cows. The results suggest the inclusion of only the important conformation traits describing udder and teats as potential traits in the selection of profitable dairy cattle in New Zealand to retain a high genetic response for milkfat yield.

GB, Nicoll, and DL Johnson

Proceedings of the New Zealand Society of Animal Production, Volume 46, , 67-70, 1986