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 Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Zollinger, W. A. Articles by Nielsen, M. K. Search for Related Content PubMed PubMed Citation Articles by Zollinger, W. A. Articles by Nielsen, M. K.

An Evaluation of Bias in Estimated Breeding Values for Weaning Weight in Angus Beef Cattle Field Records. III. Estimates of Bias due to Nonrandom Mating^1,2,3,

University of Nebraska, Lincoln 68583-0908

Abstract

Field records from 15 herds involved in the Angus Herd Improvement Records program of the American Angus Association indicated that positive assortative mating for weaning weight estimated breeding value (EBV) was being practiced. For each dam, a separate EBV was calculated from information on each progeny with all other progeny data deleted. Individual, paternal and maternal half-sib data available in all years were included in each calculation and thus, were held constant. Bias in cow EBV caused by nonrandom mating was measured as the pooled within dam regression of dam EBV on progeny's sire EBV deviated from the contemporary sire average EBV. Across herds, the average estimated bias associated with positive assortative mating ranged from .05 to .08 ratio units.

¹ Published as Paper No. 6987 Journal Series, Nebraska Agr. Exp. Sta., Lincoln and a contribution from Regional Project NC-1, Improvement of Beef Cattle Through Breeding Methods.

² Appreciation is expressed to the Amer. Angus Assoc, and fifteen cooperating breeders for providing data used in this study.

³ Anim. Sci. Dept.