Study On The Polymorphisms In UCP3, IGF2, CAPN1 Gene And Its Relationship With Carcass And Meat Quality Traits In Qinchuan Cattle And Its Hybrid Cattle

PCR–SSCP technology was applied to analyze the correlation of polymorphisms of UCP3 ,IGF2,CAPN1gene in 229 beef cattle, including Qinchuan cattle, Qinchuan×Simmental cattle, Qinchuan×Red Angus and Qinchuan×German Yellow cattle. And combined with sequencing to analysis some exons and introns of the gene,to have the research of the effect on UCP3 ,IGF2,CAPN1gene with carcass and meat quality traits.In order to provide definite theoretic foundation for excellent beef breeding.The results showed that:(1) Polymorphism in UCP3 exon 2 gene and its relationship with carcass and meat quality traitsFour genotypes (AA, AB,AC,AD) were identified in UCP3 gene exon3. The sequencing results showed that C→T(820) mutation in AB genotype, G→A(775) mutation in AC genotype , G→T(951) mutation in AD genotype respectively. The individuals of genotype AA in slaughter weight, carcass weight, carcass length, eye muscle area, water holding capacity, marbling were higher than that of genotype AB,AC,AD (P<0.05). The individuals with genotype AB were higher than those with AA, AC,AD in back fat thickness( P<0.05) .(2) Polymorphism in UCP3 intron 5 gene and its relationship with carcass and meat quality traitsThree genotypes (KK,KM,MM) were identified in UCP3 intron 5 gene,genotype AA had mutations C→A(2966, 3305,3328), C→T(3374). The individuals with genotype KK were higher than those with KM,MM in slaughter weight, carcass weight, back fat thickness, water holding capacity,marbling,tenderness(P<0.05).(3) Polymorphism in IGF2 gene and its relationship with carcass and meat quality traitsThree genotypes (AA, AB,BB) were identified of IGF2 gene,T→C (120) , A→G(279)mutations were found,statistical results indicated that significant differences in slaughter weight, carcass weight, carcass length, carcass chest depth ,eye muscle area (P<0.05). Most significant difference in thickness of back fat(P<0.01). Significant differences in marbling, tenderness , pH24 (P<0.05) ,The differences in carcass depth and water holding capacity were not significant.Genotype AA,DD were predominant genotype and A,D were predominant alleles. But the population who contain B,E allele had more excellent carcass and meat quality than others, especially in fat accumulate capacity.(4)Polymorphism in CAPN1 gene and its relationship with carcass and meat quality traits.Two genotypes (MM,MB) were identified of CAPN1 gene, T→C (1278) was found,the differences in slaughter weight, carcass weight, carcass length, carcass chest depth were not significant(P>0.05),but significant differences in eye muscle area,carcass depth and water holding capacity(P<0.05). but the differences in marbling,water holding capacity , pH24 were not significant (P>0.05). But the individuals of genotype MM had higher tenderness than individuals of genotype MM(P<0.01).