Establishment Of Jilin Luhua Chicken Dwarf Family And Analysis Of IGF-2 Gene Polymorphism

Experiment 1: Study on The Origin and Differentiation of DNA-loop Sequence Variations in Dwarf Luhua Chicken GranulesPCR and direct sequencing methods were used to determine the complete sequence of the granulosomal DNA control region of dwarf Luhua chicken,Luhua chicken,black chicken,yellow chicken,oily chicken,Wenshang Luhua chicken,and Shouguang chicken,and to compare and analyze the genetic diversity of Jilin local chicken breeds.The results showed that the complete sequence of the mt DNA control region of the dwarf Luhua chicken line,Luhua chicken,Wenshang Luhua chicken,black chicken,yellow chicken,and oily chicken was 1231 bp.A total of 43 mutation sites were detected,accounting for about 4.63% of the total nucleotide number.41 haplotypes were analyzed and divided into 4 haplotype groups(lineages).The analysis results also found that there was an average nucleotide difference(K)between Wenshang Luhua chicken and Shouguang chicken,The three indicators of nucleotide diversity(Pi)and haplotype diversity(Hd)are slightly lower than those of the Jilin local chicken population,indicating that the genetic diversity of Jilin local chickens is relatively high.The maternal lineage is formed based on the defined haplotype type.Experiment 2: Establishment of a Family of Jilin Dwarf Luhua ChickenThe experiment involved artificial insemination of 38 dwarf luhua chicken breeding roosters and 720 hens,with fertilization occurring every 5 days.Sequence analysis of 9 haplotypes was performed on 34 hens,and mixed fertilization was performed with the roosters to establish a paternal and maternal family.Observing the feather color characteristics and growth traits of the established dwarf luhua chicken family,measuring the body weight of the male and female dwarf luhua chickens at 0-21 weeks of age,using three nonlinear growth models(Logistic,Gompertz,Bertalanffy)for simulation fitting analysis,and selecting better dwarf luhua chickens for detection indicators.Comparing the growth and development indicators of parents and F1 generations at90 d,120d,and 150 d,Compare the differences in growth and development indicators between F1 male and female lines in different groups at 150 days.The results showed that 36 sets of paternal and 9 sets of maternal families were successfully established in this experiment.The growth curve was more effective in fitting the Bertalanffy model and predicting body weight of dwarf luhua chickens compared to logistic and Gompertz measurements.Among the growth and development indicators of F1 generation of dwarf luhua chickens,the 25 th group showed the best performance in body weight and chest depth,the 33 rd group showed the best body length,and the 35 th group showed the most prominent chest width,The tibia circumference and keel length of the 15 th group were the most advantageous,while the pelvic width of the 12 th group performed the best,while the tibia length of the 31 st group performed the best.Among the growth and development indicators of the female line hens of F1 generation of dwarf Luhua chicken,the weight of Group7-9(haplotype)is the most outstanding,the body length of Group 8 is the most outstanding,the chest depth of Group 4 is the most outstanding,and the pelvis width of Group 1 phenotype is the most outstanding.Experiment 3: Analysis of the correlation between gene polymorphism and growth traits of dwarf luhua chickensThe single nucleotide diversity site(SNP)in the chicken IGF-2 gene was screened through experiments.HRM analysis showed that there was a T/C mutation at position 345 of the IGF-2gene,which was associated with the 150-day growth trait of the dwarf Luhua chicken.The results showed that the mutation site was in a Hardy Weinberg equilibrium state and there were TT,TC,and CC genotypes.The TT genotype had a promoting effect on the body weight and chest depth of the dwarf Luhua chicken,The CC genotype has a certain impact on the growth and development of body slant length and tibia length in Luhua chickens,indicating a correlation between the IGF-2 gene and growth and development.