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


     


J. Anim Sci. 1976. 43:9-12.
© 1976 American Society of Animal Science

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 Coulter, G. H.
Right arrow Articles by Foote, R. H.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Coulter, G. H.
Right arrow Articles by Foote, R. H.

Heritability of Testicular Size and Consistency in Holstein Bulls1

G. H. Coulter2, T. R. Rounsaville and R. H. Foote

Cornell University3, Ithaca, New York 14853

Abstract

During the period 1967 to 1973, 4,275 measurements of scrotal circumference and 3,859 measurements of testicular consistency were made on 1,521 Holstein sires in seven bull studs providing artificial insemination service. Heritability of scrotal circumference (a predictor of total sperm output), and three similar measures of testicular consistency as predictors of semen quality and fertilizing capacity were estimated from paternal half-sib correlations. These measurements were corrected for fixed effects of year-season and age of bull within 11 6-month age groupings on bulls ranging in age from 6 to 72 months.

Heritability estimates, weighted according to the number of observations per group, averaged .67 for scrotal circumference, .30 and .22 for consistency measured with the weak and strong spring tonometers and .34 for the average of both tonometers. With these heritabilities, high repeatability, ease of taking the necessary measurements, their relationship to reproductive performance of bulls and the current low reproductive rates, it would seem desirable to place some emphasis on these traits in bull evaluation.


Footnotes

1 The authors gratefully acknowledge Dr. L. D. VanVleck, Dr. L. L. Larson and Dr. J. Hahn for their assistance, and the National Association of Animal Breeders, Eastern A. I. Coop., Inc., American Breeders Service, the North Central Biological Research Committee, and its member studs for their cooperation and financial support.

2 Present address: Agriculture Canada Research Station, Lethbridge, Alberta Canada T1J-4B1.

3 Department of Animal Science.







HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1976 by the American Society of Animal Science.