برآورد پارامترهاي ژنتيكي و فنوتيپي و روند ژنتيكي صفات رشد در گوسفند تالشي

The Estimation of genotypic trend and genetic-phenotypic parameters for growth traits in Taleshi sheep

In this study we used the data of Taleshi sheep from 1994 to 2009 were extracted from the sheep recording database of Iranian animal breeding center. Genetic parameters and (Co) variance component for age at born time and 3 and 6 month were estimated using univariate and bivariate animal models with REML by ASReml software. The highest direct Heritability for 6 monthly weight (0.305±0.01) and the lower for birth weight (0.223±0.03) were estimated and the highest maternal Heritability for birth weight (0.123±0.02) that decreased with increasing of age. Direct genetic correlations between the traits were the range of 0.28 to 0.82 and phenotypic correlations 0.27 to 0.70 and the direct -maternal genetic correlation all of traits were negative. Phenotypic average and breading value in every years was predicted by BLUP with ASReml software and total genetic progress in the end of 14 years selection by univariate and bivariate analysis were 0.0375 and 0.044 for birth weight, 0.1969 and 0.1881 for weaning weight and 0.3484 and 0.3783 (kg) for sex month weight respectively. Genetic trend of those traits also predicted and results showed that the trend of breeding value in 14 years was tangible variation increase.