Genetic Dissection of Some Production Traits of Fars Province Native Chickens Using Statistical Methods

In this research performance records of the Fars province native chickens that were recorded in breeding station during 1988 to 2002 were used. Segregation of major genes for four economically important traits including sexual maturity, egg weight, egg number and body weight were tested. For segregation testing different statistical methods including normality test, Fain test, variance homogeneity test within families (Bartlett and Leven test) and major gene index test were applied. In first step for estimation of genetic parameters a single trait animal model genetic evaluation using REML method was used. Therefore, heritabilitis of traits and breeding values of all animal's were calculated. In the second step a multiple trait genetic evaluation method for four studied traits were used and multiple traits genetic and phenotype parameters were estimated. Then by predicted BLUP breeding values of all animals (offspring and parents), major gene indices for all of traits were calculated. In conclusion, based on appropriate criteria, segregation of major genes for above mentioned traits in this population were not verified. Heritability values that were calculated with univariate model for sexual maturity, egg weight, egg number and body weight traits were 0.53±0.014, 0.63±0.014, 0.33±0.014 and 0.53±0.016, respectively. Their multiple traits estimations were 0.51±0.014, 0.64±0.013, 0.33±0.014 and 0.54±0.014, respectively. It was concluded although different statistical methods are initial recognition methods of major genes, but these methods did not show high precise and it is better to use another precise methods.