Estimation of Genetic Parameters for Growth and Body Measurement Traits in Different Ages in Iranian Makuei Sheep

The present study aimed to estimate heritability, genetic and phenotypic correlations between body weight and body measurement traits in Iranian Makuei sheep. The used data were collected from 1989 to 2012 at Makuei Sheep Breeding Station in Maku (West Azarbayjan province). The data included body weight and five body measurement traits (body length (BL), heart girth (HG), withers height (WH), rump height (RH) and leg circumference (LC)) in 6, 12 and 18 months of age with 400, 900 and 350 records in different time, respectively. The data were analyzed using multi-trait animal model through DFREML software. Results showed that the estimated heritabilities for body weight and body measurement traits in 12 months of age is less than those for 6 and 18 months of age; those comes down from 6 to 12 months of age, then go up to 18 months of age. In six months of age the highest and lowest genetic correlations were between body weight (BW) with WH and LC; respectively, and the highest and lowest phenotypic correlations were between BW with RH and LC; respectively. Genetic and phenotypic correlations between body weight in six months of age and body measurement traits were approximately high but with leg circumference were low. Genetic correlations in 12 months of age were generally higher than phenotypic correlations. Genetic correlations between body weight in 18 months of age and body measurement traits were moderate to high and the highest genetic correlation was found between body weight in 18 months of age and body length. The positive correlation between body weight and body measurements in different ages indicated that selection for body measurements would results body weight improvement.