JDS
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Journal of Dairy Science Vol. 70 No. 5 1061-1068
© 1987 by American Dairy Science Association ®
This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Meyer, K.
Right arrow Articles by Burnside, E. B.
Right arrow Search for Related Content
PubMed
Right arrow Articles by Meyer, K.
Right arrow Articles by Burnside, E. B.

Scope for a Subjective Assessment of Milking Speed

K. Meyer and E. B. Burnside

Centre for Genetic Improvement of Livestock, Department of Animal and Poultry Science, University of Guelph, Guelph, Ontario, N1G 2W1, Canada

ABSTRACT

Farmers' subjective evaluations of their cows' milking speed, scored as "very fast", "fast", "average", "slow", or "very slow", were recorded between 1982 and 1985 under Agriculture Canada's Record of Performance milk recording scheme. For the analysis, scores taken at the beginning (score 1) and the end (score 2) of the lactation were distinguished. Edited data comprised 20,909 records for score 1 and 19,012 records for score 2 for Ayrshires and 190,455 and 148,536 for Holsteins. Data were analyzed in eight subsets. The effects of herd-year-seasons (of calving), calving age, and stage of lactation when scored were evaluated and variance and covariance component estimates were obtained for sires, cows, and residuals. Heritabilities were .21 and .14 for score 1 for Holsteins and Ayrshires, respectively, and .17 and .16 for score 2. Repeatabilities were .42 and .37 for the two breeds. The scope of a sire evaluation for milking speed based on subjective scores is discussed.




This article has been cited by other articles:


Home page
 J DAIRY SCIHome page
N. R. Zwald, K. A. Weigel, Y. M. Chang, R. D. Welper, and J. S. Clay
Genetic Evaluation of Dairy Sires for Milking Duration Using Electronically Recorded Milking Times of Their Daughters
J Dairy Sci, March 1, 2005; 88(3): 1192 - 1198.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1987 by the American Dairy Science Association ®.