Research On The Mating Application And Its MtDNA Genetic Diversity Of "Yufen ?" H Line

“Yufen ?” H line was raised by Henan Agricultural University and was the female grandparent of a native egg-laying chicken breed,with light barring plumage and high reproductive performance.In order to improve the ability of seed production in high quality chickens and reduce the feeding cost of parent stock,this study was used the “Yufen ?” H line as the female and Gushi chicken A,M and“Yufen ?” D line hybrid matching.By measuring and comparing the growth performance,egg production and egg quality of the three hybrid combinations,the best combination was selected as the female parent of broiler.At the same time,the mitochondrial DNA D-loop region of “Yufen ?” H,D line and Gushi chicken A,M line were sequenced,and the haplotype,nucleotide diversity,genetic distance Index,to construct the phylogenetic tree,to explore its genetic diversity,for the future conservation and development and utilization to provide a theoretical basis.The results of this study were as follows:(1)the Weight fitting of three hybrid combinations:The growth rate of AH group was relatively fast at 16 weeks of age,and the growth rate of MH group was relatively faster after 16 weeks of age.The growth rate of DH group was relatively slower.At 20 weeks of age,the average body weight of AH group,DH group and MH group was 1115.60 g,923.41 g and 1158.78 g respectively.The average weight of 0-20 weeks of age in AH,DH and MH groups was analyzed by Logistic,Gompertz and Von-bertalanffy.The results showed that the best model of the three combinations was Von-bertalanffy model.The inflection point age of the AH group was 6.42 and the inflection point weight was 402.23 g.The inflexion age of the DH group was 6.24 and the inflection point weight was 328.81 g.the inflexion age of the MH group was 6.87 and the inflection point weight was459.76 g.(2)Correlative Analysis of Body Weight and Body Size of three hybrid combinations:Compared to the three combinations at 8,16,20 weeks of age,we found that indexes was the largest in the AH group except the tibia were the best in the MH group at the age of 8 weeks.At 16 weeks of age,there were no differences betweenMH and AH group in the tibia,chest width,keel long.The other tibials were the largest in MH group.At 20 weeks of age,the results were consistent with the 16 weeks of age.In the correlation analysis,the correlation between the oblique length and body weight was the highest at 8 and 16 weeks of age,and the correlation coefficients were0.900 and 0.824 respectively.At 20 weeks of age,the correlation between chest width and body weight was the largest,the correlation coefficient was 0.617.At 8 weeks of age,the correlation was the largest between body weight and body length in DH group,the correlation coefficient was 0.903.But at 16 weeks and 20 weeks of age,maximum tibial and chest depth had the most relavent to the weight,the correlation coefficient were For 0.783 and 0.780.In the MH group,body length and body weight of the largest related,the correlation coefficient was 0.803 at the age of 8 weeks.At16 weeks and 20 weeks of age,Chest depth and hip width had the most relavent to the weight,and the correlation coefficients were 0.644 and 0.577.(3)Comparative analysis on laying performance and egg quality of three hybrid combinationsIn terms of laying performance,DH > AH > MH;When the egg production rate reached 50%,the age of DH and AH were shorter than the MH group for one week,the body weight of MH > AH > DH and significant difference between each other,the egg weight no difference between each other.In the egg quality determination,in addition to protein height and Hastelloy two indicators for the larger DH group,the other indicators are the largest MH group.Among them,the egg weight of MH group was 47.15 g,which accorded with the standard of imitation of native eggs weight;AH group and DH group were 44.54 g,44.99 g respectively,which were in accordance with the standard of native eggs weight.In the Haugh unit,AH group was 86.830,DH group was 89.413,MH group was 86.217,belong to AA grade.(4)Genetic diversity of mt DNA in four linesIn this experiment,the sequence of mt DNA D-Loop first hypervariable region of A,D,M and H lines was analyzed.The results showed that the sequence length of the first hypervariable region was 606 bp.A total of 28 mutant loci and 17 haplotypes were found in 118 individual sequences,all of which were mutated mutations.The genetic diversity and genetic distance of four lines were studied.The results showed that the genetic diversity of the A,D and H lines was more abundant,while the Mlines were relatively conserved.The four lines had two maternal origins,and the genetic distances between the four lines were close to each other.