Study On The Relationships Between Polymorphisms Of Chicken MyoG MyoD Gene And Slaughter And Meat Quality Traits

Great progress has been made in poultry breeding in the past years. While dailygaining of body weight and the ratio of meat to food and resistance to disease in chickenhave been improved considerately, the intensive selection in chicken breeding has resultedin some negative effects. This asked the breeders aim at improving the chicken Quality.MyoD gene family includes MyoG, MyoD, Myf5 and Myf6. This gene family controlsthe whole muscle development process: from pre-muscle cell's tying, propagation andconform of muscle fiber to the maturation and the function-completing of postnatalindividual. So MyoD gene family is very important to the vertebrate in differentiation ofmuscle cell and developmental maturation of skeletal system, and that the analysis ofMyoD gene family has theoretical and practical significance in poultry′s breeding.PCR-SSCP. technique and DNA sequencing were applied in this study that wasdesigned to investigate the effect of MyoG and MyoD gene on broiler meat and carcasstraits. The broilers from Sichuan Daheng Poultry Breeding Company and Animal ScienceAcademy were used in this research.Four mutations at MyoG Promoter region were found among (T/C, locusA),(T/A,T/C, A/G, locusB) individuals in each line. The least square analysis showed that there wassignificant difference between genotypes and breast muscle percentage and some carcasstraits (P＜0.05) for locus A; and there was a significant difference(P＜0.05) between AC,AA and AB genotypes and breast muscle weight for locus B; there was a significantdifference(P＜0.05) between CC and AC genotypes and leg muscle percentage for locus B,and there was a extremity significant difference(P＜0.01) in between all genotypes andmuscle fibre density for both locus A and locus B. There was no significant difference (P＞0.05) in the other triats. The breast muscle weight and breast muscle percentage of AAand AC genotype were higher than that of others genotypes. According to the association analysis between carcass and meat traits with SNP inexon 2 of the MyoD gene, the results of least square analysis shown there was nosignificant difference (P＞0.05) beteween genotypes and carcass traits; BB genotype hadhigher muscle fibre density than that of AA genotype and the difference was verysignificant difference(P＜0.01) between genotypes and meat traits, and BBgenotype havelower Matter Content than that of others genotype. It was concluded from the results thatBB homozygote have possible binding with Muscle Fibre Diameter and tenderness in chicken.It was concluded from the results that MyoG and MyoD gene may be the candidate geneaffecting the muscle fiber traits of chicken or it links with QTL, and the mutation may beused as the molecular genetic marker to select the chickens for Meat Quality traits.