Growth Analysis And Genome Wide Association Analysis Of Production Traits In Lingkun Chickens

Understanding the growth,egg production and egg quality of local chicken breeds will help to make further use of the advantages of chicken breeds in China.Due to the long-term introduction of foreign layer ancestors in China,the high-quality resources of local layer are limited and wasted.Through molecular marker assisted breeding technology,we can find the candidate genes that affect the performance of laying hens,which can improve the performance of laying hens.In order to study the growth and development law of Lingkun chicken,the growth curve of Lingkun chicken at 0-12 weeks old was drawn,and the correlation between growth traits and egg quality traits of Lingkun chicken was analyzed.In order to study the quantitative trait loci(QTLs)and key candidate genes affecting the production performance of Lingkun chickens,300 of more than 1700 Lingkun chickens were randomly selected at 72 weeks of age for blood sample collection,determination of phenotypic data related to production performance,extraction of genomic DNA,and genotyping of 266 finally qualified samples by whole genome resequencing technology after quality testing,The generalized linear model in tassel software was used for genome-wide association analysis.The experiment set two significance levels:extremely significant correlation P<1.89E-06 and significant correlation P<9.47E-08.The test results are as follows:1.Logistic model can best fit the growth and development process of Lingkun chicken;Lingkun chicken grew slowly before 3 weeks of age,grew rapidly from 3 to 10 weeks of age,and then slowed down;Lingkun egg shell thickness was significantly correlated with egg weight.2.a total of 8 SNPs were detected in the whole genome,which were significantly associated with the age of the first day of production and 14 SNPs were significantly associated with the egg production at week age.GAL,CENPF,GPC2,PEMT,TFAP2D,DCDC2,NRSN1 and CPQ genes were found near these loci.3.In the whole genome,four new SNPs were detected that were significantly associated with eggshell strength,two SNPs were significantly associated with eggshell thickness,and one SNPs was significantly associated with Harrington units.SLC5A,UPP1,FHOD3,NCALD,RNF2,SLIT3,PSMB2 and TTLL7 genes were found near these loci.At the same time,the QTL region significantly related to eggshell strength was 3.77 Kb(5358928-5362697 bp)on GGA13.