Effect of porcine IL-6 polymorphism on litter size traits in commercial pig breeds
Authors:   Department of Animal and Aquatic Sciences, Faculty of Agriculture, Chiang Mai University, Chiang Mai 50200, Thailand, Norseeda Worrarak ,   Center of Excellence on Agricultural Biotechnology: (AG-BIO/PERDO-CHE), Bangkok 10900, Thailand,   Graduate School, Chiang Mai University, Chiang Mai 50200, Thailand, Liu Guisheng ,   Institute of Animal Science and Veterinary Medicine, Hubei Academy of Agricultural Sciences, Wuhan 430064, China,   Hubei Key Lab for Animal Embryo Engineering and Molecular Breeding, Wuhan 430064, China, Teltathum Tawatchai ,   Mae Hong Son Livestock Research and Breeding Center, Mae Hong Son 58000, Thailand, Sringarm Korawan ,   epartment of Animal and Aquatic Sciences, Faculty of Agriculture, Chiang Mai University, Chiang Mai 50200, Thailand,   Cluster of Research and Development of Pharmaceutical and Natural Products Innovation for Human or Animal, Chiang Mai University, Chiang Mai 50200, Thailand, Naraballobh Watcharapong ,   Department of Animal and Aquatic Sciences, Faculty of Agriculture, Chiang Mai University, Chiang Mai 50200, Thailand, Khamlor Trisadee ,   Department of Animal and Aquatic Sciences, Faculty of Agriculture, Chiang Mai University, Chiang Mai 50200, Thailand, Krutmuang Patcharin ,   Department of Entomology and Plant Pathology, Faculty of Agriculture, Chiang Mai University, Chiang Mai 50200, Thailand, Mekchay Supamit ,   Department of Animal and Aquatic Sciences, Faculty of Agriculture, Chiang Mai University, Chiang Mai 50200, Thailand,   Center of Excellence on Agricultural Biotechnology: (AG-BIO/PERDO-CHE), Bangkok 10900, Thailand,   Cluster of Research and Development of Pharmaceutical and Natural Products Innovation for Human or Animal, Chiang Mai University, Chiang Mai 50200, Thailand,   Innovative Agriculture Research Center, Faculty of Agriculture, Chiang Mai University, Chiang Mai 50200, Thailand
Published: November 2021

This study aimed to verify the polymorphisms in the porcine IL-6 gene and to elucidate its effects on litter size traits in Large White and Landrace sows. Four single nucleotide polymorphisms (SNPs) of the porcine IL-6 gene (g.91506415A>G, g.91507983A>G, g.91508173C>T, and g.91508716C>T) were genotyped using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. There was no polymorphism observed on the three SNPs (g.91506415A>G, g.91507983A>G, and g.91508716C>T) of the porcine IL-6 gene. The porcine IL-6 g.91508173C>T polymorphism was found to be segregating in Large White and Landrace sows. The porcine IL-6 g.91508173C>T polymorphism was significantly associated with the total number born (TNB) and the number of piglets weaned alive (NWA) traits in Large White sows (P<0.05). Moreover, the porcine IL-6 g.91508173C>T polymorphism was significantly associated with the TNB, number born alive (NBA), and NWA traits in Landrace sows (P<0.05). These results indicated that the porcine IL-6 g.91508173C>T polymorphism was associated with litter size traits. These findings confirmed the importance of the IL-6 gene as a candidate gene for litter size traits in pigs.