Variance component and heritability estimation of carcass traits using different models

The objective of this study was to estimate heritability and variance components in beef cattle for carcass traits using additive, dominance, and epistatic models. Quality control of the genotypic data was performed using PLINK (V. ۱.۰۷). Variance components and heritability for each trait were estimated using GVCBLUP (V. ۳.۹). Additional analysis was conducted for the estimation of epistatic variance and other variance components using PEPIS software. Results estimation of heritability for carcass quality traits showed that most of the traits have a high heritability, but heritability for the Ultrasonic rib eye area was low(۰.۱۵). Our results demonstrated that until dominance variance is moderate and low, gblup doesn’t affect by the dominance effect, but if the portion of dominance variance is high, can be expected that gblup and animal rank based on gblup is different. When the PEPIS program was used for the estimation of the variance component, the heritability results for all traits were higher in comparison with GVCBLUP. PEPIS results could be beneficial for imaging of genetic structure.