• Journal of Animal Science and Technology
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• v.65 no.5
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• pp.912-921
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• 2023

Genetic diversity analysis is crucial for maintaining and managing genetic resources. Several studies have examined the genetic diversity of Korean domestic chicken (KDC) populations using microsatellite markers, but it is difficult to capture the characteristics of the whole genome in this manner. Hence, this study analyzed the genetic diversity of several KDC populations using high-density single nucleotide polymorphism (SNP) genotype data. We examined 935 birds from 21 KDC populations, including indigenous and adapted Korean native chicken (KNC), Hyunin and Jeju KDC, and Hanhyup commercial KDC populations. A total of 212,420 SNPs of 21 KDC populations were used for calculating genetic distances and fixation index, and for ADMIXTURE analysis. As a result of the analysis, the indigenous KNC groups were genetically closer and more fixed than the other groups. Furthermore, Hyunin and Jeju KDC were similar to the indigenous KNC. In comparison, adapted KNC and Hanhyup KDC populations derived from the same original species were genetically close to each other, but had different genetic structures from the others. In conclusion, this study suggests that continuous evaluation and management are required to prevent a loss of genetic diversity in each group. Basic genetic information is provided that can be used to improve breeds quickly by utilizing the various characteristics of native chickens.

• Korean Journal of Poultry Science
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• v.44 no.2
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• pp.83-92
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• 2017

The purpose of this study was to estimate the inbreeding level and effective population size of Korean indigenous chickens. In the study, two variables were considered to evaluate the pedigree completeness: (1) the proportion (%) of animals with complete pedigree, and (2) the proportion of animals with inbreeding coefficients greater than zero. In the proportion of animals having complete pedigree, all strains reached almost 100% completeness in 1~2 years. In the proportion of animals with inbreeding coefficients greater than zero, all strains reached almost 100% completeness in 5~6 years. We considered that the pedigree recoding system is well managed and that the inbreeding coefficient is a reliable measure. Over the past 20 years, the increase of inbreeding coefficients in Korean indigenous chicken strains has been 7.6~10.9%. The S strain showed the most rapid increase of inbreeding coefficient of 8.2% in 10 years. The reason for this rapid increase is considered to be associated with the fact that the numbers of sires and dams involved in reproduction was 115 and 91, respectively, which are lower than those of the other strains. According to average rates of increase in inbreeding coefficients (${\Delta}F$), all strains have ${\Delta}F$ values of 0.39~0.85%, which is lower than 1%, and the effective population size is above 50. The results showed that inbreeding levels were within the acceptable range and that Korean indigenous chicken population scan be regarded as safe from the threat of extinction.

• Journal of Animal Science and Technology
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• v.55 no.3
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• pp.185-194
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• 2013

Microsatellite markers have been a useful genetic tool in determining diversity, relationships and individual discrimination studies of livestock. The level of genetic diversity, relationships among two Korean indigenous chicken brand populations (Woorimatdag: WR, Hanhyup3: HH) as well as two pure populations (White Leghorn: WL, Rhode Island Red: RIR) were analyzed, based on 26 MS markers. A total of 191 distinct alleles were observed across the four chicken populations, and 47 (24.6%) of these alleles were unique to only one population. The mean $H_{Exp}$ and PIC were estimated as 0.667 and 0.630. Nei's $D_A$ genetic distance and factorial correspondence analysis (FCA) showed that the four populations represented four distinct groups. However, the genetic distance between each Korean indigenous chicken brand (WR, HH) and the pure population (WL, RIR) were threefold that among the WR and HH. For the STRUCTURE analyses, the most appropriate number of clusters for modeling the data was determined to be three. The expected probabilities of identity among genotypes of random individuals (PI) were calculated as $1.17{\times}10^{-49}$ (All 26 markers) and $1.14{\times}10^{-15}$, $7.33{\times}10^{-20}$ (9, 12 with the highest PI value, respectively). The results indicated that the brand chicken breed traceability system employing the own highest PI value 9 to 12 markers, and might be applicable to individual identification of Korean indigenous chicken brand.