Abstract:

Abstract: This study was designed to analysis the effects of ESR、FSH-β and PRLR genes on litter size in three introduced swine (Landrace、Large Yorkshire、Duroc )of Liaoning province, single genotype effects as well as combined genotype effects were all studied, PCR-RFLP were applied to detect polymorphism of three genes. The results showed that there were there genotypes: AA、AB and BB for ESR、FSH-β and PRLR gene, the distributed difference of genotype was not significant(P＞0.05)，it was in genetic equilibrium for three genes. The results of single genotype effects showed that all LSM of the litter size had a gradually increasing tendency AA、AB and BB in turn, BB genotype of ESR and FSH-β gene were the superior one, but it was AA for PRLR gene. The results of combined genotype effects showed that BBBBAA was the dominant combination, there were significant differences （P＜0.05）or very significant differences（P＜0.01）in the combined genotypes effects, and the combined genotypes effects was higher than single genotypes effects. In conclusion, reproductive traits of swine could be improved by applying marker-assisted selection of combining genotypes.