This paper analyzes the characteristics of the performance test and Landrace boars to: Dutch, Swedish, German and Danish, originating from large farms in Serbia in order to analyze the variability of different characteristics of the aggregate genotype: feed conversion, daily gain and thickness of the back side of bacon and lean meat. Systemic genetic factors (race and fathers) and environmental factors (farm) have a highly significant effect (P<0.01) on the properties of the aggregate genotype (feed conversion and meat percentage) except for the traits daily gain and backfat thickness of the side, where impact of race was not significant (P>0.05). The tested properties of the aggregate genotype showed a high degree of heritability (heritability) with a high standard error. Heritability for feed conversion was 0.84 ± 0.21 for daily gain 0.73 ± 0.18,backfat thickness of 0.74 ± 0.19, the thickness of the side of bacon 0.76 ± 0.19 and percent of meat 0,66 ± 0.18. The positive genetic correlations between traits in the aggregate genotype (from 0.266 between feed conversion and backfat thickness side to 0.984 between backfat thickness and the thickness of the side), and negative genetic correlations between the percentage of meat and feed conversion, daily gain and the thickness of the back side of bacon thickness (-0.155, -0.344, -0.904 and -0.858), were found.