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


     

Journal of Dairy Science Vol. 75 No. 1 288-293
© 1992 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 Similar articles in PubMed
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 Silva, H. W.
Right arrow Articles by Morse, D.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Silva, H. W.
Right arrow Articles by Morse, D.

Factors Affecting Days Open, Gestation Length, and Calving Interval in Florida Dairy Cattle

H. W. Silva 1, C. J. Wilcox 1, W. W. Thatcher 1, R. B. Becker 1, and D. Morse 1

1 Dairy Science Department, University of Florida, Gainesville 32611

Effects of several factors on reproductive performance were evaluated. Mean performance and number of observations were for days from parturition to first service, 93 and 7730; days from first to successful service, 35 and 11,751; days open, 123 and 8571; gestation length, 280 and 13,612; and calving interval, 400 and 8524. Data covered 52 yr during which no detectable trends in calving interval occurred; other variables changed slightly. Jerseys had 8 fewer d from parturition to first service, 16 fewer d from first service to conception, 8 fewer d open, and 8-d shorter calving intervals than did Guernseys and Holsteins, which did not differ. Cows freshening in warm rather than cool weather suffered by 7, 7, 12, and 13 d for these variables. Repeatabilities ranged from .05 to .12; heritabilities were .05 and .06. Nonmaternal estimate of heritability of gestation length was .22. Phenotypic and genetic correlations between days from parturition to first service and calving interval were .48 and .87; for days open and calving interval, they were .97 and .96. Although days from first to successful service were essentially uncorrelated with days open and calving interval phenotypically (.05), genetic correlations were greater than 1.0 and estimated as unity. Results show no discrepancy between estimates for measures of reproductive performance in a subtropical environment and numerous studies in temperate areas. Large studies from subtropical areas are sparse; essentially none concerns long-term trends.

Key Words: Florida • subtropical • reproduction

Submitted on May 31, 1991
Accepted on July 12, 1991




This article has been cited by other articles:


Home page
 J DAIRY SCIHome page
R. C. Goodling Jr., G. E. Shook, K. A. Weigel, and N. R. Zwald
The Effect of Synchronization on Genetic Parameters of Reproductive Traits in Dairy Cattle
J Dairy Sci, June 1, 2005; 88(6): 2217 - 2225.
[Abstract] [Full Text] [PDF]

Home page
 J DAIRY SCIHome page
S. Oseni, I. Misztal, S. Tsuruta, and R. Rekaya
Genetic Components of Days Open Under Heat Stress
J Dairy Sci, September 1, 2004; 87(9): 3022 - 3028.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1992 by the American Dairy Science Association ®.