Genetic relationship of meat and milk production in Finnish Ayrshire

Genetic relationships of meat and milk production traits were studied from a field data set of 50 852 Finnish Ayrshire bulls and heifers and 28 362 Fi nnish Ayrshire cows, using REML methodology and animal model. Studied meat production traits included carcass weight, fatness and fleshiness for all b ulls, heifers and cons, and additionally heifer and mature live weights est imated based on heart girth circumference for cows. Milk production traits included first lactation 305-d milli fat and protein yield, and fat and pro tein percentage for the all the slaughtered cows. Genetic correlations betw een bull/heifer and cow meat production traits varied between - 0.20 and 0. 68, with higher and positive correlations between corresponding traits in b oth data subsets. Genetic correlations between bull/heifer meat production traits and cow milk production traits were either positive and low (with yi eld traits) or close to zero (with composition traits). (C) 2001 Elsevier S cience B.V. All rights reserved.