Study of Genetic and Phenotype Trends of Some of Growth Traits in Moghani Sheep

In this research 17620 records of growth traits of Moghani sheep breed collected during 1994 to 2005 in sheep breeding station of Jafar-Abad, were used to estimate the genetic and phenotypic trends. The Best Linier Unbiased Prediction (BLUP) from breeding value was estimated by Derivative Free Restricted Maximum Likelihood (DFREML) with univariate and multivariate animal model. The trends were estimated by regression of mean of estimated breeding and phenotypic values on birth year. Phenotypic trends were positive and significant (P<0.05) for birth and 3 months weights and are negative for 6 months, 9 months and yearling weights. Genetic trends were positive and significant for all traits in both models for lamb weights at birth, 3 months, 6 months, 9 months and yearling of age being 0.0055, 0.0053, 0.0052, 0.0061 and 0.0849 kg per year in univariate analysis (P<0.01) and 0.0107, 0.0968, 0.1311, 0.1613 and 0.1328 kg per year in multivariate analysis (P<0.01), respectively. Multivariate model offered better results in comparison with univariate models.