Growth Curve Fitting,Carcass Performance Measurement And Association Analysis Of MSTN And MyoD In Meat Duck Q2 Line

Growth performance and carcass performance are two important indexes in animal production.In this study,the body weight of white feather duck(Q2 line)female ducks at 0-43 weeks of age was measured by 10 different weeks of age and carcass performance of male ducks at 6 weeks of age,the association analysis of each index is also carried out;MSTN and MyoD genes related to growth and development were selected as candidate genes,firstly,the mutation sites of MSTN and MyoD exon fragments were identified by DNA-Pooling seHuencing,then MSTN exon1 and MyoD introne1 were genotyped by PCR-SSCP,analysis of the association between MSTN,MyoD gene polymorphism and growth indexes based on typing results,this study provided a reference for breeding of white feather duck(Q2 line)and molecular marker assisted selection breeding.The main research results are as follows:1.Three growth curve models,Logistic,Gompertz and Bertalanffy,were used to fit the body weight of white feather duck(Q2 line)female ducks at 10 different weeks of age,the fitting degree R2 values were 0.976,0.991 and 0.995,respectively.The growth rate rhythm of white-feathered duck(Q2 line)is more in line with Bertalanffy model.2.The carcass performance of white feather duck(Q2 line)male at 6 weeks old was determined.The carcass rate,half eviscerate ratio,eviscerate ratio and lean meat rate(%)average is respectively were 90.01±3.99,84.25±4.01,77.74±4.12 and 23.19±4.33.DNA-Pooling method was used to identify polymorphic loci on exons of MSTN and MyoD genes in white-feathered duck(Q2 line)male ducks.Results three mutation loci were found in MSTN gene,namely,T458C at exonl,A5464G at exon3 and G529A at introne1,in which exonl suddenly became synonymous mutation without causing amino acid changes.Two mutant loci were found in MyoD gene,namely intronel A576G and C598T.3.The results of polymorphism distribution showed that the polymorphism information content of MSTN T458C locus was 0.27,which was in moderate polymorphism.The polymorphism information content at the mutation site of MyoD A576G was 0.29,which was in moderate polymorphism.Chi-sHuare test showed that the population was in Hardy-Weinberg eHuilibrium.4.Using one-way ANOVA analysis,there were three genotypes of CC,CT and TT in the exonl 458 bp of MSTN gene,among which TT genotype was significantly higher than CC genotype in live weight,carcass weight,half eviscerate weight and eviscerate weight(P<0.05),there was no significant difference in other indicators among genotypes(P>0.05).There were three genotypes of GG,GA and AA in introne1576bp of MyoD gene,among which GA genotype was significantly higher than GG genotype in leg muscle weight(P<0.05),and there was no significant difference among the genotypes in other indexes.The growth and development model of white feather duck(Q2 line)was fitted,and the Bertalanffy model had the best effect.MSTN gene T458C and MyoD gene A576G can be used as a reference for breeding white feather duck(Q2 line)production traits.