Estimation of inbreeding and genetic parameters on conformation traits of the Iranian Arab horses

Arab horse is one of the popular pure breed in Iran that is registered by World Arabian Horse Organization (WA. H. O.). In this research 13 conformation traits were studied on a random sample of the Iranian Arab horses. Animal model with Derivative Free Restricted Maximum Likelihood (DF-REML) approach and DFREML software were used to estimate variance components of traits. Mean of the inbreeding coefficient for the population under study was 2. 12 percentage. The inbreeding coefficient of each horse was considered as a covariate. The effect of inbreeding on the whithers height (P<0. 01)، mid body، croup height and fore and back canon bones circumference was significant (P<0. 05). The lowest and highest heritability were equal to (0. 050 ± 0. 008) and (0. 614 ± 0. 087) and related to neck length and croup height respectively. This research was done at Islamic Azad University، Ghaemshahr Branch in (2007).