Study On The Hybrid Of Landrace And Jinhua Pig And It's Candidate Genes Influencing Meat Quality Traits

The PCR-RFLP and PCR-SSCP techniques were applied to analyze the polymorphism of myogenin(MyoG) gene, heart fatty acid binding protein(H-FABP) gene,melanocortin-4 receptor(MC4R) gene, cathepsin B(CTSB) gene, cystatin B(CSTB) gene, rendement napole(RN) gene in the hybrid of Landrace and Jinhua pig, the hybrid of Jinhua pig and Pietrain, and Pietrain pigs. The SPSS software was used to analyze the effect of MyoG,MC4R,CSTB and RN on growth traits(daily gain, slaughter weight, carcass percentage) and meat quality traits(pH value of leg muscle and eye muscle, temperature of leg muscle and eye muscle, meat color, the proportion of myofibrils types, water holding capacity, and density of muscles fiber ).The results were as following.There were only monomorphisms found in the 3' end and the promoter of MyoG gene, and the second intron and the 5' upstream region of H-FABP gene, CTSB gene, the missense mutation loci of CSTB gene in the hybrid of Landrace and Jinhua pigs. The genotypes frequencies of AA,AB,BB for MyoG(in the second intron) were 0.35,0.65 0 respectively. The genotypes frequencies of 11,12,22 for MC4R were 0.5556,0.4444,0 respectively. The genotypes frequencies of 11,12,22 of CSTB(CysB 2)were 0,0.4444,0.5556 respectively. The genotypes frequencies of RK/RN,RN7rn+,rn+/rn+ of RN were 0,0.7037,0.2963 respectively.No significant effect was found for the MyoG gene,MC4R gene, CSTB gene with daily gain, slaughter weight, carcass percentage, pH value of leg muscle and eye muscle, temperature of leg muscle and eye muscle, meat color, the proportion of myofibrils types, water holding capacity, and density of muscles fiber in the hybrid of Landrace and Jinhua pigs(P > 0.05).Significant associations were found for the RN locus with lightness in the hybrid of Landrace and Jinhua pigs. In the same time, we have found that the genotype of RN7m+ has low pH value, water holding capacity , lightness, redness, yellowness,but high density of muscles fiber compare to genotype of rn+/rn+, this results are agreed with the results of Europe and American scientists.