Genetic effect and combined genotype effect of ESR, FSHß, 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 ß subunit (FSHß), 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 FSHßBB 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, FSHßB, CTNNAL1G, miR-27aA allele was favorable for litter size traits. Furthermore, combined genetic effect analysis showed ESRAAFSHßBB, ESRAACTNNAL1CG, ESRAAmiR-27aAA, FSHßBBCTNNAL1CC, FSHßBBmiR-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.