Genetic effect and combined genotype effect of ESR, FSHβ, CTNNAL1 and miR-27a loci on litter size in a Large White population

Abstract

To select new Large White line with high number of piglets born, genotypes of estrogen receptor (ESR), the follicle stimulating hormone β subunit (FSHβ), catenin alpha like 1 (CTNNAL1) and miR-27a were tested in 472 Large White sows. The associations of different genotypes with litter size traits were also studied. The results showed ESRBB and FSHβBB sows produced 0.41–1.49 more pigs per litter (p < .05) for total number born (TNB) and number born alive (NBA) than did other corresponding genotypes. TNB of CTNNAL1CG sows is 0.50 more pigs per litter (p < .05) than that of CTNNAL1GG sows with the dominance effect of 0.25 pigs per litter (p < .05). miR-27aBB sows had a less estimated breeding value (EBV) to TNB and had a more number of mummified pigs (NM) than did miR-27aAA or miR-27aAB sows (p < .05). Therefore, ESRB, FSHβB, CTNNAL1G, miR-27aA allele was favorable for litter size traits. Furthermore, combined genetic effect analysis showed ESRAAFSHβBB, ESRAACTNNAL1CG, ESRAAmiR-27aAA, FSHβBBCTNNAL1CC, FSHβBBmiR-27aAA and CTNNAL1CG miR-27aAB was the favorable combined genotype for litter size traits. These results identified favorable alleles and genotypes for litter size traits and suggested a potential selection scheme for litter size in Large White pigs.