Crossbreeding Test And Slaughter Performance Of Jilin Luhua Chicken And Jilin Black Chicken Analysis Of Related Gene Polymorphisms

In recent years,the development of broilers is more and more rapid.Compared with large chickens,consumers pay more and more attention to the quality,flavor and tenderness of meat.Local chickens have good flavor and meat quality,but there are problems such as low feed conversion rate and poor population uniformity.Jilin Black Chicken,Jilin Luhua Chicken and Jilin Aijiao Luhua Chicken are all high-quality local varieties from Jilin Province.These varieties have strong resistance to roughage,cold and disease.Jilin Black Chicken has excellent meat production performance,and Jilin Luhua Chicken has outstanding reproductive performance.In order to obtain a better population,the complete diallel cross method was selected for breeding.Through the determination of the growth performance and phenotypic traits of the hybrid F1 generation,the analysis of the growth fitting curve,the determination of slaughter performance and the way of molecular assisted selection,it is hoped that a more comprehensive evaluation of the F1 generation can be carried out,and a more excellent population can be found,which provides a theoretical basis for the breeding and development and utilization of local chickens.Experiment 1 : Analysis of Crossbreeding Effect between Jilin Black Chicken and Jilin Luhua Chicken In the experiment,the complete diallel cross method was used to conduct the experiment among Luhua Chicken,Aijiao Luhua Chicken and Jilin Black Chicken.The feather appearance characteristics,growth body size traits,slaughter traits,feed conversion ratio and corresponding heterosis of the parent group and the hybrid group were observed.The body weight of male and female in each hybrid group at 0 – 21 weeks old was measured.Finally,three nonlinear growth models(Logis-tic,Gompertzpertz and Bertalanffy)were used for fitting analysis,and better hybrid combinations were selected by comparing each detection index of nine combinations of F1 generation.The results showed that :(1)When black chicken was the male parent and Luhua chicken was the female parent,the F1 cocks were all Luhua feather color,and the hens were all non-Luhua feather color(black chicken feather color).When Luhua chicken is male parent,its F1 generation both male and female are Luhua feather color.There were significant(p < 0.05)or extremely significant(p < 0.01)differences in each index of hybrid combinations at different age stages.LA showed completely positive heterosis at 90 and 120 days of age,and the highest heterosis rate of body weight was 17.58 %.HA showed completely positive heterosis at 150 days of age,and the highest heterosis rate of body weight was 20.79 %.The results showed that the combination of LA and HA had better growth performance,which improved the growth performance of dwarf Luhua chicken.(2)The growth and development rules of the F1 generation of the three parents and different hybrid combinations were similar.They all showed an accelerating trend with the positive weight gain at the age of 9 weeks,with the highest weight gain at the age of 9 weeks,and then gradually decreased.Three growth modelsExperiment 2 : Correlation analysis of H-FABP gene polymorphism on slaughter performance of different hybrid chicken breeds(1)To verify the effect of H-FABP gene intron 1 mutation site and its polymorphism on meat flavor,especially IMF content in Jilin Luhua chicken and Jilin black chicken populations.In this study,Kompetitive Allele-Specific PCR(KASP)was used to analyze the polymorphism of H-FABP gene in three parental populations of Jilin Luhua Chicken,Aijiao Luhua Chicken and Jilin Black Chicken and six positive and negative cross populations,and the correlation between meat quality and slaughter performance of the above nine populations was analyzed.The results showed that there was G / A mutation in intron1 of H-FABP gene in 9 F1 populations,and there were three genotypes GG,GA and AA.AA genotype in 9 chicken populations showed dominant genotype in AL population;GA genotype was dominant in LL,AA,LA,HL and HA populations;GG genotype showed dominant genotype in HH and AH populations;The frequencies of AG genotype and GG genotype were the same in LH population.In AL population,A gene was the dominant gene,and G gene was the dominant gene in the other eight populations.Hardy-Weinberg equilibrium test results showed that HH,LA,AL,HL,LH and AH in the nine different chicken breeds were in equilibrium at A / G site(p > 0.05),while LL,AA and H were in equilibrium.Experiment 3 : Correlation analysis of RB1 gene polymorphism on slaughter performance of different hybrid chicken breeds Intron 13 of RB1 gene had A / G mutation and three genotypes of AA,AG and GG in Jilin Luhua Chicken,Jilin Aijiao Luhua Chicken,Jilin Black Chicken and their reciprocal crosses.HRM analysis showed that A gene was the dominant gene only in LL and HA populations,and G gene was the dominant gene in the other seven populations.Hardy-Weinberg equilibrium test results showed that LA population was in an unbalanced state at this locus,indicating that gene expression was affected by artificial selection and was subjected to great selection pressure.The nine populations were moderate polymorphism(0.25 < PIC < 0.5)and low heterozygosity.AG genotype improved the tenderness of breast muscle and water retention of leg muscle,and increased the tenderness of breast muscle in HL and HA populations.GG genotype improved the water retention of pectoral muscle in HA and AH populations,thereby improving the quality of muscle.The results confirmed that the A / G mutation of RB1 intron was a potential locus affecting slaughter traits,which could be used as a molecular marker for chicken IMF screening.Therefore,this locus can be used as a theoretical basis for the breeding of high-quality chicken in the hybrid offspring of Jilin Black Chicken and Jilin Luhua Chicken.