EN
C-banding identified centromeric heterochromatin polymorphism, most often located in a pair no 16, was a basis for selecting animals for the experiment.The aim of the experiment was to assess the impact of centromeric heterochromatin polymorphism on pig fertility, expressed by litter size.The research included the first two litters obtained from 30 pairs of parent with different genotypes as regards the parameter under study.A statistical analysis of the number of offspring from different mating types showed no significant differences between the experimental groups of animals.The results obtaned did not confirm suggested correlation between polymorphism of the centromeric heterochromatin regons and pig fertility, estimated by mean size.Thus the polymorphism cannot be regarded as a selection criterion.