HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Rennie, J. C. Articles by Burnside, E. B. Search for Related Content PubMed Articles by Rennie, J. C. Articles by Burnside, E. B.

Environmental and Genetic Parameters for Type Traits in Holstein Cows¹

Department of Animal and Poultry Science, University of Guelph, Guelph, Ontario, Canada

ABSTRACT

Data consisted of 11 type appraisal traits for 51,044 Holstein first calf heifers with age at classification from 25 to 36 mo. Effects of 10 rounds, 12 monthly ages at classification, 12 monthly stages of lactation, and 12 months (season) of classification were analyzed by least-squares. Effects of these four environmental factors were significant in most cases although the squared multiple correlation for the complete model ranged from 1 to 3% for various type traits. Heritabilities from adjusted and unadjusted data were final score .19, .33; final classification .27, .28; general appearance .27, .28; dairy character .22, .23; body capacity .31, .31; mammary system .17, .19; fore udder .14, .17; rear udder .15, .16; legs and feet .07, .08; rump .33, .34; and body size .52, .55. Genetic correlations among type traits were positive and ranged from .06 between dairy character and legs and feet to 1.18 between final score and final classification. Phenotypic correlations were generally smaller than genetic correlations.

¹ Supported by N.R.C. grant 572–39 awarded to J. C. Rennie.