Polymorphism of chosen candidate genes and their relation to reproductive traits in sows

The aim of the current study was to examine the relation between the polymorphism of RBP4 (Retinol-binding protein 4) genes and reproductive traits. The experimental material consisted of 367 sows of commercial line 990. The following traits were included in the study: total number born, number born alive, number of piglets at 21 days of age, number of weaned piglets, litter weight at 21 days of age, litter weight at weaning. The relation between the genotypes and the reproductive traits was estimated with the least squares method. The RBP4 locus genotype was found to have a significant effect on: total number born, number born alive and litter weight at weaning, based on an analysis of records from the first parity of each sow. In all cases the highest value of the traits was observed in animals having 2/2 homozygote. No significant effect of these genotypes was noted in relation to litter size after analyzing records from the 1 to 5 parities of each sow. The only trait significantly associated with this genotype was litter weight at the 21(st) day of age.