Application Of Molecular Markers For Recessive White Feather On Chicken Breeding

Poultry consumption accounts for a great proportion in China. The flavor of meat falling down with the improvement of the level of intensive. Requirement of meat qualityand flavor of people have changed and Chinese prefer to live chicken, colored feather getpeople’s preference in many areas. Producing new varieties with tasty meat flavor and appearance to meet consumer demand is urgently needed for poultry breeders.The breedingof the new species of recessive white chicken can not only make commercial generation have the appearance of local chicken, but also improve the meat quality.This research usemarker-assisted selection breeding technology to accelerate the process of the breeding ofthe new species of white chicken, which may lay a foundation for cultivating chicken breed of high quality.Depending on previous laboratory establishment the dominant white locus andrecessive white locus molecular markers,studying recessive white chicken which wereraised in chicken breeding farm in Henan Innovative Engineering Research Center ofPoultry Germplasm Resources,using genotyping technology to select and remainhomozygous individuals to seed, applied to the new strains practice of recessive whitechicken breeding. Meanwhile,combining with the test cross group and the group parentand offspring genotype and phenotype contrast, to evaluate the efficacy of the applicationof molecular markers in the breeding.Selection500chicken in the recessive white chicken group, collection blood fromwing vein, extraction DNA, adopting marker-assisted selection technology to determinethe genotype of I, C locus, which controled white character. According to genotypedetermination results, selected and remained recessive homozygous individual (iiccgenotype), pedigree breeding and artificial insemination, collected eggs for15days,observed the F1generation feather color, randomly extracted F1generation individuals todetermine the genotype of I, C locus. The results showed the groups we selected andremained were recessive homozygous, the offspring feather color of pedigree breedingwere white, I, C locus genotypes were recessive homozygous,that indicated the accuracyrate we choosed was100%. Selecting iicc genotype recessive white male parent mated with known genotypefemale parent randomly,artificial insemination,collected eggs for15days, individualhatch,statistics feather color of F1generation and compared with theoretical value tostudy the reliability of genotyping. In selfing verification group, its theory genotype wasconsistent with markers genotype determination results, feather color conformed totheory phenotype.There were some white spots individuals which were caused by geneinteractions in IiCc genotype offspring,while some white spots individuals whose feathercolor deepened along with raising in iiCc genotype offspring.Selecting Gushi male parent(n=12) mated with recessive iicc genotype femaleparent(n=60),and iicc genotype recessive white male parent(n=12) mated with Gushifemale parent (n=60),male:female=1:5, raised in single cage, individual hatch. Recordingand observing the color segregation of F1generation, determining the genotype of I, Clocus of F1generation. In test cross verification group，its theory genotype was consistentwith markers genotype determination results, F1generation phenotypic characterconformed to theory phenotype.There were some white spots individuals whose feathercolor deepened along with raising in iiCc genotype offspring.Results: This research applied dominant white and recessive white molecular markerin the new strains recessive white chicken breeding, after marker screening hybridsoffspring white ratio reached99%.At the same time, using test cross,the method oftraditional breeding commonly used,to evaluate the results of molecular markers, testcross progeny colored feather ratio were above90%. Reciprocal cross were identical,showed gene controled white trait on autosoma.This study effectively improved theefficiency of the selection, sped up the breeding process, laid a solid foundation for themolecular marker practice and application in the recessive white chicken new strains.