Abstract:

The aim of this study was to analyze the effects of single and combined genotypes of MyoG and c-fos genes on muscle fiber traits in pig. Large White(180) and Beijing Black pigs（170）were used as experimental animals. The frozen section, H-E and SDH staining technology were used to detect the partial meat quality and muscle fiber traits. PCR-SSCP was used to detect the SNPs of MyoG and c-fos genes, the genotype frequency of SNPs were calculated, and the association of SNPs with partial meat quality and muscle fiber traits were analyzed. The results showed that: (1) A polymorphism site was detected in exon1 of MyoG gene, and three kinds of genotypes(AA, AB, BB) were detected; Two polymorphism sites were detected in exon4 of c-fos gene, and three kinds of genotypes(AA, AB, BB) were detected, respectively; (2) In the two pig breeds, the muscle fiber area and diameter decreased, and muscle fiber density increased with the increase of the allele A frequency at A2512G site. The muscle fiber density and percentage of red muscle fiber enhanced with the increase of the allele B frequency at G2650A site. And the allele A and B had significant effects on muscle fiber area and density at A2910G site; (3) The phenotype values of different traits(except for backfat thickness) had significant difference between individuals with favorable and unfavorable combined genotypes in Beijing Black pigs(P＜0.05 or P＜0.01), the phenotype values of different traits(except for backfat thickness and percentage of middle muscle fiber) had significant difference between individuals with favorable and unfavorable combined genotypes in Large White pigs(P＜0.05 or P＜0.01). The results indicate that the single nucleotide polymorphisms and combined genotypes of MyoG and c-fos genes have effect on the muscle fiber traits in pig, they could be considered as the candidate genes for muscle fiber traits.