Estimation of (Co)Variance Components of Egg Quality Traits for Fars Native Fowls

Economically success incomerical and Native laying hen farms in some eaten is related to egg quality. So, egg quality is a one of the most important factor affecting hatchability and lead to increasing the egg demand. The current study was carried out in aim to estimate the genetic parameters for egg quality traits in Fars native fowls. To do this, 2000 pedigree recorded eggs were collected at Fars Native Breeding Center and external and internal egg quality traits were measured. Significance of environmental effects determined using GLM procedure by SAS software and those were considered in the mixed model analysis. Heritability, genetic and phenotypic correlations were estimated using ASREML software. The estimated heritability for egg weight and external egg quality traits including shell strength, shell weight, shell thickness were 0.21, 0.44, 0.23, 0.12. this parameter for internal egg quality traits including albumin height, albumin weight, Hough unit, yolk weight, yolk diameter were also estimated 0.17, 0.10, 0.17, 0.36, 0.13, respectively. Genetic and phenotypic correlations of egg weight with external and internal (except to yolk weight) egg quality traits were obtained positive. Both genetic and phenotypic correlations among external egg quality traits were found positive and ranged from 0.04 to 0.91. Yolk weight were negatively genetically correlated with yolk diameter and shell features (shell strength, shell thickness and shell weight). The genetic correlation of shell strength and traits such as albumin height, Hough unit, yolk weight and yolk diameter were low and in negative direction. The results showed that the selection for increasing egg weight lead to improvement of egg quality traits and decreased yolk weight in Fars native fowls.