Estimation of genetic parameters for performance and body measurement traits in Duroc pigs selected for average daily gain, loin muscle area, and backfat thickness

Genetic parameters for performance and body measurement traits were estimated from a new line of purebred Duroc pigs selected during nine generations for average daily gain (ADG), loin muscle area (LMA), and backfat thickness (BF). Two animal models, which included or excluded the litter common random effect, were used to estimate genetic parameters. Common litter effects on most body measurement traits as well as performance traits proved to be important. Heritability estimates for body measurement traits ranged from 0.13 to 0.44. The genetic correlations among body length, withers height, chest depth, and hip height were estimated to be positive (0.17-0.86). Those among fore width, chest width, and hind width were also estimated to be positive (0.23-0.83). There were negative genetic correlations between the former and the latter traits (-0.82 to -0.30). Numerous genetic correlations between performance and body measurement traits were found to be favorable from medium to high. Our results indicate that selection using body measurement traits which have favorable genetic correlations such as chest width for ADG (0.39), hind width for LMA (0.32), and chest girth for BF (0.60) may be useful for improving performance traits.