• 농업과학연구
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• 제48권3호
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• pp.527-534
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• 2021

This study investigated the possibility of performing selection using 30-month carcass traits by estimating the genetic parameters of 24- and 30-month carcass traits. Data used in this study were the carcass traits of 13,151 heads slaughter at the age of 24 and 30 months. As a result of the study, the heritability of backfat thickness, carcass weight, eye muscle area and marbling score at 24 months of age were estimated to be 0.588, 0.354, 0.467 and 0.587, respectively. The heritability of backfat thickness, carcass weight, eye muscle area and marbling score at 30 months of age were estimated to be 0.498, 0.577, 0.505 and 0.530, respectively. The ranking correlation was 0.516 between the carcass selection indices of 24 and 30 months of age. By providing a 30-month selection index, it is possible to use semen suitable for farm profits, and more semen information can be provided to farms than previously. Furthermore, studies on a selection index based on 30-month carcass traits are needed to provide highly accurate information.

• Asian-Australasian Journal of Animal Sciences
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• 제21권8호
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• pp.1109-1115
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• 2008

The reproduction component traits are important components of sow efficiency. The objective of this study was to evaluate the phenotypic and genetic parameters of four reproduction component traits (age at puberty (AP), preweaning number dead (PND), weaning to service interval (WSI), and intra-individual SD in litter size (IISDLS)) of sows in two Chinese indigenous pig breeds. Available reproductive records including 22,591 piglets born from 2,054 litters by 574 Jiangquhai sows and 464 Meishan sows were used in this investigation. A set of mixed models and restricted maximum likelihood methodology were used for the multiple trait analyses of these traits. The results showed that the estimates of heritabilities (${\pm}$standard error) for AP, PND, WSI and IISDLS were $0.40{\pm}0.05$, $0.06{\pm}0.03$, $0.20{\pm}0.02$ and 0.09{\pm}0.03 in Jiangquhai sows, and $0.35{\pm}0.06$, $0.05{\pm}0.03$, $0.18{\pm}0.03$ and $0.10{\pm}0.04$ in Meishan sows, respectively. There was moderate genetic correlation between AP and WSI, while there were low genetic correlations between the other pairwise traits. The genetic correlations were positive for most of the pairwise traits, except for the one between AP and IISDLS. The results indicated that all traits except for AP were difficult to make genetic improvement by traditional selection methods due to low heritabilities and the favorable improvement of AP might result in unfavorable changes of IISDLS due to the trend of genetic antagonism.

• Journal of Animal Science and Technology
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• 제50권5호
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• pp.601-612
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• 2008

본 연구는 한우의 체형과 체중이 일령에 따라 어떻게 변화하며, 선발형질인 도체형질과의 상관 또한 체중 및 체형의 변화에 따라 어떠한 형태로 변화하는지 알아보기 위하여 실시하였다. 분석에 이용한 형질은 체중, 체형 및 도체형질을 포함하여 모두 17가지 형질이며 거세우 161두의 자료를 이용하였다. 성장곡선 추정은 logistic 모형을 이용하였고, 추정한 모수를 토대로 변곡일령 및 변곡일령에서의 특성을 다시 계산하였다. 각 형질에 대한 성장곡선 모수를 분석한 결과 좌골폭은 조숙성, 흉위는 만숙성 형질인 것으로 나타났다. 등지방두께에 대한 흉심, 흉폭 및 요각폭의 순위상관계수는 6~24개월까지 꾸준히 증가하는 반면 다른 체형형질들은 18개월령 이후에 감소하는 것으로 나타났다. 본 연구는 표현형 자료에 대한 분석만이 이뤄졌으나, 한우 성장 단계에 따른 유전적 변화를 살펴보기 위해 유전모수 추정과 같은 추가적인 연구가 이뤄진다면 체형형질을 한우개량에 충분히 이용이 가능할 것으로 생각된다.

• 한국패류학회지
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• 제32권4호
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• pp.249-254
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• 2016

북방전복을 대상으로 성별에 따른 성장형질의 변이를 이용한 선발육종의 가능성 여부를 확인하고자, 실제로 암수 1:1 수정을 통하여 10가계를 생산 관리하여 성별에 따른 성장형질의 표현형 측정과 유전모수를 추정하였다. 그 결과 성비율은 1:1로 일반적 전복류의 성비와 같은 결과를 나타내었으며, 성별에 따른 성장은 모든 성장형질에 있어 암컷이 수컷보다 유의적으로 큰 것으로 나타났다 (p < 0.05). 이러한 결과는 선발을 할 때 성별에 따른 성장차이를 이용하여 양식전복의 성장률 향상을 할 수 있는 가능성을 시사하고 있다.

• Asian-Australasian Journal of Animal Sciences
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• 제22권5호
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• pp.747-755
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• 2009

The feed resource for animals is a major cost determinant for profitability in livestock production enterprises, and thus any effort at improving the efficiency of feed use will help to reduce feed cost. Feed conversion ratio, expressed as feed inputs per unit output, is a traditional measure of efficiency that has significant phenotypic and genetic correlations with feed intake and growth traits. The use of ratio traits for genetic selection may cause problems associated with prediction of change in the component traits in future generations. Residual feed intake, a linear index, is a trait derived from the difference between actual feed intake and that predicted on the basis of the requirements for maintenance of body weight and production. Considerable genetic variation exists in residual feed intake for cattle and pigs, which should respond to selection. Phenotypic independence of phenotypic residual feed intake with body weight and weight gain can be obligatory. Genetic residual feed intake is genetically independent of its component traits (body weight and weight gain). Genetic correlations of residual feed intake with daily feed intake and feed conversion efficiency have been strong and positive in both cattle and pigs. Residual feed intake is favorably genetically correlated with eye muscle area and carcass weight in cattle and with eye muscle area and backfat in pigs. Selection to reduce residual feed intake (excessive intake of feed) will improve the efficiency of feed and most of the economically important carcass traits in cattle and pigs. Therefore, residual feed intake can be used to replace traditional feed conversion ratio as a selection criterion of feed efficiency in breeding programs. However, further studies are required on the variation of residual feed intake during different developmental stage of production.

• Asian-Australasian Journal of Animal Sciences
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• 제30권9호
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• pp.1239-1244
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• 2017

Objective: This study was conducted to estimate breed-specific variance components for total number born (TNB), number born alive (NBA) and mortality rate from birth through weaning including stillbirths (MORT) of three main swine breeds in Korea. In addition, the importance of including maternal genetic and service sire effects in estimation models was evaluated. Methods: Records of farrowing traits from 6,412 Duroc, 18,020 Landrace, and 54,254 Yorkshire sows collected from January 2001 to September 2016 from different farms in Korea were used in the analysis. Animal models and the restricted maximum likelihood method were used to estimate variances in animal genetic, permanent environmental, maternal genetic, service sire and residuals. Results: The heritability estimates ranged from 0.072 to 0.102, 0.090 to 0.099, and 0.109 to 0.121 for TNB; 0.087 to 0.110, 0.088 to 0.100, and 0.099 to 0.107 for NBA; and 0.027 to 0.031, 0.050 to 0.053, and 0.073 to 0.081 for MORT in the Duroc, Landrace and Yorkshire breeds, respectively. The proportion of the total variation due to permanent environmental effects, maternal genetic effects, and service sire effects ranged from 0.042 to 0.088, 0.001 to 0.031, and 0.001 to 0.021, respectively. Spearman rank correlations among models ranged from 0.98 to 0.99, demonstrating that the maternal genetic and service sire effects have small effects on the precision of the breeding value. Conclusion: Models that include additive genetic and permanent environmental effects are suitable for farrowing traits in Duroc, Landrace, and Yorkshire populations in Korea. This breed-specific variance components estimates for litter traits can be utilized for pig improvement programs in Korea.

• Journal of Crop Science and Biotechnology
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• 제11권2호
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• pp.83-90
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• 2008

Two hundred and sixty Korean soybean landrace accessions were analyzed for polymorphism at 92 simple sequence repeat(SSR) loci. The 995 identified alleles served as raw data for estimating genetic diversity and population structure. The number of alleles at a locus ranged from three to 27 with a mean of 10.4 alleles per locus. $F_{ST}$ values estimated by analysis of molecular variance(AMOVA) using SSR data set were 0.018, 0.027, and 0.016 for usage, collection site and maturity groups, respectively, indicating little genetic differentiation. The model-based clustering analysis placed the accessions into three clusters(K=3) with 0.0503 of $F_{ST}$, indicating moderate genetic differentiation. Duncan's Multiple Range Test at K = 3 on the basis of 18 quantitative traits revealed that one cluster was mainly differentiated from the other two clusters by seed related traits and the other two clusters were differentiated from each other by biochemical traits. Genetic structure of Korean soybean landraces was differentiated by model-based clustering and supported by their phenotypic traits in part. This preliminary study could be the first step towards more efficient germplasm management and utilization of soybean landraces and helpful in association studies between genotypic and phenotypic traits in Korean soybean landraces.

• Asian-Australasian Journal of Animal Sciences
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• 제33권4호
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• pp.525-530
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• 2020

Objective: The purpose of this study was i) to identify the characteristics of carcass traits in Chikso by gender, region, age at slaughter, and coat color using the carcass data collected from the nationwide pedigree information and coat color investigation, and ii) to estimate genetic parameters for breed improvement. Methods: A linear model was used to analyze the environmental effects on the carcass traits and to estimate genetic parameters. Analysis of variance was performed using TYPE III sum of squares for the unbalanced data provided by the general linear model procedure. Variance components for genetic parameters was estimated using REMLF90 of the BLUPF90 family programs. Results: Phenotypic performance of carcass weight (CW), eye muscle area (EMA), and backfat thickness (BF) in Chikso were lower than those of Hanwoo. This is a natural outcome because Hanwoo have undergone significant efforts for improvement at the national level, a phenomenon not observed in Chikso. Another factor influencing the above outcome was the smaller population size of Chikso compared to that of Hanwoo's. The heritabilities of CW, EMA, BF, and marbling score in Chikso were estimated as 0.50, 0.37, 0.35, and 0.53, respectively, which were was higher than those of Hanwoo. Conclusion: Based on the genetic parameters that were estimated in this study, it is expected that the carcass traits will improve when the livestock research institutes at each province conduct small-scale performance tests and the semen is provided to farmers after selecting proven bulls using the state-of-art selection technique such as genomic selection.

• 동의생리병리학회지
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• 제19권2호
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• pp.304-314
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• 2005

The major concept of Sasang typology is that the disease susceptibility and drug response as well as physiological characteristics are presumed to be different depending on their Sasang types. Although characterizing fundamental basis of their traits are crucial in this research field, only pathological susceptibility and physical appearances were thoroughly studied. We evaluated their physiological characteristics by tapping psychological, physical and genetic traits of each Sasang types. After determining the Sasang type of one hundred three college students based on the Questionnaire for the Sasang Constitution Classification, the psychological, physical and genetic traits of each type were analyzed with the Myers-Briggs Type Indicator (MBTI), Bioelectrical Impedance Analysis and genetic polymorphism test, respectively. Each of the Sasang types showed significantly different profiles (Generalized estimation equation, coef=11.88, z=2.13, p=0.033), and could be distinctively classified based on their MBTI scores (discriminant analysis Wilks Lambda=0.611, df=8, chi-square=36.7, p<0.001). Subjects with the So-Eum type (Introversion and Judging) and the So-Yang type (Extroversion and Perceiving) showed contrasting psychological features, however they had similar anthropometric characteristics. Subjects with the Tae-Eum type showed bigger Body Mass Index ($R^2$=0.22, df=4, 74, F=5.07, p=0.001) and body shape compared to others. Although there were no significant differences in G-protein beta-3 subunit polymorphism, angiotensin-converting enzyme polymorphism and Methylenetetrahydrofolate reductase polymprhisms among groups with Sasang types, it was shown that the dopamine system could be one for genetic marker for Sasang typology. These results demonstrated distinctive and essential traits of Sasang typology using reproducible psychometric, anthropometric and genetic evaluations. We also found that the Sasang typology was a bio-psychological typology which could show trait-specific guideline for individualized medicine.

• Plant Resources
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• 제1권1호
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• pp.26-32
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• 1998

This paper describes the variations in eight agronomic traits in three unadapted local landraces and an inbred cultivar of corn. To compare the agronomic traits in field evaluation with molecular marker evaluation the genotypes of the plant introduction were also checked by 4 microsatellite-SSR loci. The variations of the eight agronomic traits were higher in the local landrades than in the inbred line. which was substantiated by the high genetic variation in the landrades with microsatellite-SSR loci. The level of genetic variation was also different between landraces. Since the genetic evaluation can be easily quantified by the analysis of microsatellite-SSR loci. the threshold level of genetic homogeneity in the population for parental lines in breeding program can be determined and the effort of maintaining the landrace population would be alleviated. As an example in our analysis. the entry from Whachon should not need the same number of selfing generations as the other two landraces to get the level of inbred state. Since this line showed lowest intra-genetic variation within the population.