Screening Of Microsatellite Markers For Paternity Identification Of Muscovy Ducks

In modern breeding,in order to obtain varieties corresponding to market demand,sometimes it is necessary to carry out selective crosses.Selection requires the knowledge of the relationship between parents and offspring.As a result of breeding,the establishment of the paternity test system is particularly important.In this study,in order to screen out the combination of microsatellite loci used to establish the Muscovy duck paternity identification system,the polymorphism and exclusion probability of multiple microsatellite(STR)loci were analyzed,and the suitable loci selected were used for combination.To establish a Muscovy duck paternity identification system to detect the error rate of pedigree records of breeding populations and provide a reference for individual breeding to reduce the loss caused by incorrect pedigree records.The experimental samples in this study were N101 and N104 Muscovy ducks,a total of 1056,of which 96 N101 strains were randomly sampled,and N104 strains were 960 Muscovy ducks(27 males,397 females,and 536 parental pedigrees).The offspring of N104 is sampled according to the family and used to verify the accuracy of the paternity test system.Genotype analysis was performed on the samples with 30 STRs,the sites that could not be successfully amplified were eliminated,the genetic diversity information of the remaining sites was analyzed and the joint exclusion probability was calculated to determine the establishment of the Muscovy duck paternity test system.The results show that: 20 of the 30 microsatellite sites can be successfully amplified,and 19 of them have clear bands,and the amplification effect is good.Polymorphism analysis of 20 loci revealed that APH15 and APH18 had only one genotype and no polymorphism.The average number of alleles in the other 18 loci is 6.1,and the average observed heterozygosity is 0.674.The average expected heterozygosity is 0.615,the average polymorphism information content is0.550,of which 6 are moderate polymorphism sites and 12 are highly polymorphic.Among the 18 sites,when the cumulative number of sites reached 13,CEP-1P,CEP-2P and CEPPP were 0.9999,0.99971,and 1,respectively,which were greater than 99%,99.9%,and99.99%,respectively In order to increase the accuracy of the core sites of duck paternity testing,the cumulative sites were increased to 15,and the CEP-1P,CEP-2P,and CEP-PP were 0.993251376,0.999808091,and 1,which were greater than 99% and 99.9%,respectively.And 99.99%.Conclusion: In this study,15 microsatellite molecular markers(APH04,APH20,APH23,APL77,APL80,APL82,APL83,CAUD011,CAUD013,CAUD026,CAUD037,CAUD070,CAUD075,CAUD092,CAUD114)were screened to construct the Muscovy duck paternity identification system.