Comb size as an indicator of reproductive traits in acclimatize white Leghorn cockerels: Improvement in reproductive traits breeding values associated with selecting according to comb size

Abstract

This study was conducted at the Poultry Farm / Animal Resources Department, College of Agriculture, Baghdad University, and over the period from 15/10/2004 until 30/9/2005, used 24 sires ,144 dam and 217 progeny . The aim of this study was to obtain genetic improvement of certain reproductive traits (semen volume, packet cell volume, sperms movement scales, fertility, hatchability, alkaline phosphatase, total protein and body weight) for white Leghorn by indirect selection according to comb size using traits breeding values that obtained by animal model program . Results obtained showed there were wide variance in traits means ( expressived as standard deviation) that referred to take advantage of this traits in reproductive indirect selection programs especially movement scales , fertility and hatchability. Results referred also that there were genetic improvement in some of reproductive traits [expressed as significant (p< 0.05) raise breeding values means]. There were significant genetic improvement (p< 0.05) take place in most of studied traits in progeny stock because of elite sires selected dependence comb size, that emboldening to use comb size as an indicator in selection programs . Depressions in standard deviation of breeding values were occurred when indirect selection processes, that to be necessary of using large stock . The results supported used comb size for cock’s reproductive traits improvement in progeny flocks.