Region by Sire Interaction for Reproduction Traits in Beef Cattle

Abstract
Region by sire interactions for birth weight and weaning weight were evaluated using 12,933 edited field records from the American Simmental Association. Records from eight regions of the United States were studied. Region, management unit within region and sire were generally significant scources of variation for both traits. In general, the effect of the region × sire interaction was nonsignificant for birth weight but was significant for weaning weight. The region × sire interaction variance component was less than 2% of the total variance for both traits. Genetic correlations of the sires' progeny performance among regions ranged from .86 to 1.00 for birth weight and from .73 to .78 for weaning weight in three analyses. Copyright © 1978. American Society of Animal Science . Copyright 1978 by American Society of Animal Science