J. Anim Sci.
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

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 Google Scholar
Google Scholar
Right arrow Articles by Van Vleck, L. D.
Right arrow Articles by Cundiff, L. V.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Van Vleck, L. D.
Right arrow Articles by Cundiff, L. V.

Journal of Animal Science, Vol 76, Issue 6 1528-1534, Copyright © 1998 by American Society of Animal Science

JOURNAL ARTICLE

Sex effects on breed of sire differences for birth, weaning, and yearling weights

L. D. Van Vleck and L. V. Cundiff
Roman L. Hruska U.S. Meat Animal Research Center, Lincoln, NE, USA.

Weights of males and females can be considered to be correlated traits with different averages and variances. This study attempted to determine whether defining traits as expressed in males or in females would change estimates of breed of sire differences needed to calculate across-breed factors for adjustment of within-breed EPD to across-breed EPD. Records from the US Meat Animal Research Center of progeny of Hereford, Angus, and MARC III composite dams mated to 12 sire breeds that had been used to calculate breed of sire adjustments in 1996 were used. Breeds of sire were Hereford, Angus, Shorthorn, Brahman, Simmental, Limousin, Charolais, Maine-Anjou, Gelbvieh, Pinzgauer, Tarentaise, and Salers. Female and male records for birth (BWT), weaning (WWT), and yearling (YWT) weights were considered to be separate although correlated traits. Heritability estimates for expression as females and males were as follows: .44 and .47 for BWT, .25 and .19 for WWT, and .55 and .49 for YWT. Corresponding genetic correlations between expression in males and females were .85, 1.00, and .92. Phenotypic standard deviations were slightly larger and coefficients of variation slightly smaller for males than for females; the largest differences were for YWT. Breeds ranked similarly for female and male weights; the major exception was Brahman for BWT. Averages of breed of sire contrasts for expression in females and males were almost identical to contrasts from analyses of combined male and female records. Largest differences between averaged and combined breed of sire contrasts were approximately 1 kg for BWT and WWT and approximately 2 kg for YWT. The results show that considering male and female weights as separate traits is not needed in calculation of across-breed adjustment factors from US Meat Animal Research Center records.




HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1998 by the American Society of Animal Science.