• Asian-Australasian Journal of Animal Sciences
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• 제21권2호
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• pp.177-180
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• 2008

In this study, cattle microsatellite markers recommended for diversity studies of cattle by the EU AIRE 2066 Concerted Action Group were used to study the genetic diversity of 105 Thai swamp buffalo which were randomly selected from eight different research stations of the Department of Livestock Development, Thailand. Of 34 primer pairs, 16 were successfully amplified while the rest showed non-specific amplification. The lowest number of alleles was two while the highest was nine, with an average of 4.7 alleles per locus. The average unbiased heterozygosity for all eight populations was 0.5233, with a low of 0.4772 (Samui) and a high of 0.5616 (Burirum). The genetic distance ranged from 0.0574 to 0.2575. Populations from Lopburi and Burirum showed the closest relationship, whereas Srisagat and Samui were the most divergent. The results generated with the primers recommended by the EU AIRE 2066 Concerted Action Group are at a slight variance from our previous study, possibly as a result of the number of specific amplification products obtained, suggesting that cattle markers may not be optimal for studies of the genetic diversity of the Thai swamp buffalo.

• Journal of Ecology and Environment
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• 제36권3호
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• pp.205-210
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• 2013

Cicuta virosa L. (Apiaceae) is a perennial emergent plant designated as an endangered species in South Korea. According to the former records, only four natural habitats remain in South Korea. A former study suggested that three of four populations (Pyeongchang: PC, Hoengseong: HS, Gunsan: GS) would be classified as different ecotypes based on their different morphological characteristics and life cycle under different environmental conditions. To evaluate this suggestion, we estimated genetic diversity in each population and distance among three populations by random amplification of polymorphic DNA. Seven random primers generated a total of 61 different banding positions, 36 (59%) of them were polymorphic. Nei's gene diversity and the Shannon diversity index increased in the order of PC < HS < GS, which is the same order of population size. In the two-dimensional (2D) plot of first two principal components in principal component analysis with the presence of 61 loci, individuals could be grouped as three populations easily (proportion of variance = 0.6125). Nei's genetic distance for the three populations showed the same tendency with the geographical distance within three populations. And it is also similar to the result of discriminant analysis with the morphological or life-cycle factors from the previous study. From the results, we concluded that three different populations of C. virosa should be classified as ecotypes based on not only morphology and phenology but genetic differences in terms of diversity and distance as well.

• Asian-Australasian Journal of Animal Sciences
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• 제15권12호
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• pp.1690-1694
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• 2002

Genetic parameters were estimated for birth weight and weaning weight from three year (1991-1993) data totalling 1100 records of 25 rams to 205 ewes of Indigenous Sabi flock maintained at Grasslands Research Station in Zimbabwe. AIREML procedures were used fitting an Animal Model. The statistical model included the fixed effects of year of lambing, sex of lamb, birth type and the random effect of ewe. Weight of ewe when first joined with ram was included as a covariate. Direct heritability estimates of 0.27 and 0.38, and maternal heritability estimates of 0.24 and 0.09, were obtained for birth weight and weaning weight, respectively. The total heritability estimates were 0.69 and 0.77 for birth weight and weaning weight, respectively. Direct-aternal genetic correlations were high and positive. The corresponding genetic covariance estimates between direct and maternal effects were positive and low, 0.25 and 0.18 for birth weight and weaning weight, respectively. Responses to selection were 0.8 kg and 0.14 kg for birth weight and weaning weight, respectively. The estimated expected correlated response to selection for birth weight by directly selecting for weaning weight was 0.26. Direct heritabilities were moderate; as a result selection for any of these traits should be successful. Maternal heritabilities were low for weaning weight and should have less effect on selection response. Indirect selection can give lower response than direct selection.

• Structural Engineering and Mechanics
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• 제68권5호
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• pp.549-561
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• 2018

Sobol method is applied as a powerful variance decomposition technique in the field of global sensitivity analysis (GSA). The paper is devoted to increase convergence speed of the extracted Sobol indices using a new proposed sampling technique called genetic based Latine hypercube sampling (GBLHS). This technique is indeed an improved version of restricted Latine hypercube sampling (LHS) and the optimization algorithm is inspired from genetic algorithm in a new approach. The new approach is based on the optimization of minimax value of LHS arrays using manipulation of array indices as chromosomes in genetic algorithm. The improved Sobol method is implemented to perform factor prioritization and fixing of an uncertain comprehensive high speed rotor-bearing system. The finite element method is employed for rotor-bearing modeling by considering Eshleman-Eubanks assumption and interaction of axial force on the rotor whirling behavior. The performance of the GBLHS technique are compared with the Monte Carlo Simulation (MCS), LHS and Optimized LHS (Minimax. criteria). Comparison of the GBLHS with other techniques demonstrates its capability for increasing convergence speed of the sensitivity indices and improving computational time of the GSA.

• 농업생명과학연구
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• 제44권2호
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• pp.29-38
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• 2010

본 연구에서는 2000년부터 2008년 사이에 출생한 Duroc종, Landrace종 및 Yorkshire종 종돈의 총 31,455두의 농장검정 자료를 이용하여 다형질 동물 모형과 다변량 모체효과 모형에 의한 돼지 경제형질의 유전적 분산성분을 추정하였다. 품종별 조사된 각 형질에 있어서 다변량 모체효과 모형을 이용하여 추정된 상가적 효과에 의한 유전력이 모체효과에 의한 유전력보다 모두 높게 나타났으며, 다형질 동물 모형에서 상가적 효과만 고려했을 때의 유전력이 다변량 모체효과 모형에서 추정된 상가적 효과의 의한 유전력보다 대부분 높게 추정되었다. 다변량 모체효과 모형을 이용하여 추정된 모체효과에 의한 육종가와 표현형가와의 상관관계에 있어서 대부분 낮은 정(+)의 상관이거나 강한 부(-)의 상관관계를 보여 품종별 각 형질에 있어서 모체효과를 적절히 고려하여 육종가와 표현형의 상관관계를 높인다면 보다 나은 개량을 도모 할 수 있을 것으로 사료된다.

• Asian-Australasian Journal of Animal Sciences
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• 제31권5호
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• pp.636-642
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• 2018

Objective: The objective of this study was to estimate genetic parameters of milk, fat, and protein yields within and across lactations in Tunisian Holsteins using a random regression test-day (TD) model. Methods: A random regression multiple trait multiple lactation TD model was used to estimate genetic parameters in the Tunisian dairy cattle population. Data were TD yields of milk, fat, and protein from the first three lactations. Random regressions were modeled with third-order Legendre polynomials for the additive genetic, and permanent environment effects. Heritabilities, and genetic correlations were estimated by Bayesian techniques using the Gibbs sampler. Results: All variance components tended to be high in the beginning and the end of lactations. Additive genetic variances for milk, fat, and protein yields were the lowest and were the least variable compared to permanent variances. Heritability values tended to increase with parity. Estimates of heritabilities for 305-d yield-traits were low to moderate, 0.14 to 0.2, 0.12 to 0.17, and 0.13 to 0.18 for milk, fat, and protein yields, respectively. Within-parity, genetic correlations among traits were up to 0.74. Genetic correlations among lactations for the yield traits were relatively high and ranged from $0.78{\pm}0.01$ to $0.82{\pm}0.03$, between the first and second parities, from $0.73{\pm}0.03$ to $0.8{\pm}0.04$ between the first and third parities, and from $0.82{\pm}0.02$ to $0.84{\pm}0.04$ between the second and third parities. Conclusion: These results are comparable to previously reported estimates on the same population, indicating that the adoption of a random regression TD model as the official genetic evaluation for production traits in Tunisia, as developed by most Interbull countries, is possible in the Tunisian Holsteins.

• Asian-Australasian Journal of Animal Sciences
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• 제19권10호
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• pp.1379-1383
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• 2006

A total of 6,804 records for Duroc breed were collected from three farms registered at the Korean Animal Improvement Association (KAIA) from 1998 to 2004 of which both records from two ultrasound modes (A and B) were analyzed to estimate the variance components of carcass traits. Three carcass traits backfat thickness (bf), loin eye muscle area (lma) and lean meat percentage (lmp) were measured. These traits were analyzed separately as bf1, lma1 and lmp1 for ultrasound mode A and bf2, lma2 and lmp2 for ultrasound mode B with multiple trait animal model by using MTDFREML (Boldman et al., 1993). All the traits revealed medium heritability values. Estimated heritabilities for bf1, bf2, lma1, lma2, lmp1 and lmp2 were 0.45, 0.39, 0.32, 0.25, 0.28 and 0.39, respectively. Estimated genetic correlations for traits bf1 and bf2, lma1 and lma2, lmp1 and lmp2 were positive but low. Specifically, genetic correlations between bf1 and bf2 was 0.30 while the estimates for lean traits between lma1 and lma2 and between lmp1 and lmp2 were 0.15 and 0.18, respectively. Conversely, high negative genetic correlations existed between bf1 and the lean traits lma2, lmp2. Likewise, the estimated genetic correlations between lma1 and lma2 and lmp1 and lmp2 were low.

• Asian-Australasian Journal of Animal Sciences
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• 제6권3호
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• pp.433-440
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• 1993

Means and standard errors of 285 Taiwan's local chicken and 429 Single Comb White Leghorn pullets at 35 wk of age were: egg weight (g) $48.3{\pm}0.3$, $54.6{\pm}0.3$, shell index $73.39{\pm}0.26$, $73.20{\pm}0.18$, shell color $15.23{\pm}0.40$, $0.88{\pm}0.27$, shell whiteness $72.61{\pm}0.57$, $90.00{\pm}0.35$, shell strength ($kg/cm^2$) $3.77{\pm}0.07$, $3.35{\pm}0.05$, shell thickness (mm) $0.38{\pm}0.003$, $0.38{\pm}0.002$, Haugh units $85.26{\pm}0.50$, $91.81{\pm}0.38$ and yolk percent (%) $30.17{\pm}0.18$, $27.32{\pm}0.16$ respectively. Theestimated heritabiliities of Taiwan's local chicken based on sire and dam components of variance were as follows: egg weight 0.20, shell index 0.1, shell color 0.87, shell whiteness 0.79, shell strength 0.37, shell thickness 0.14, Haugh units 0.24 and yolk percent 0.16. Genetic correlations based on sire and dam components of variance and covariance were also estimated. Generically, the shell index was positively correlated with egg weight, shell strength and yolk percent, and egg weight was negatively correlated with shell thickness, Haugh unit and yolk percent.

• Animal cells and systems
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• 제12권2호
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• pp.77-83
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• 2008

The canine fearfulness is a behavioral trait known to have a genetic basis. This research analyzed genetic effects of the dopamine D4 receptor polymorphism on this behavior by postulating a mixed model of inheritance. Genotyping for the three different repeat polymorphism found in the third exon of the receptor gene was carried out for the population of the Korean native dogs. Four hundred fifty eight dogs with known pedigree were genotyped, and 264 individuals were tested for their fear responses to an experimenter, in which four different behavioral paradigms were adopted. Since the results assessed by principal factor analysis revealed a major factor explaining 69% of the total phenotypic variance, the subsequent analyses were conducted for this quantity. Analyses of the factor scores by estimating their posterior means indicated that there is a fixed effect exerted by the three different repeat polymorphism found in the D4 receptor as well as sex, in addition to unidentified polygenic effects. The phenotypic contribution of the D4 genotype was roughly estimated to be about 2%, which is a fraction of the total genetic effects responsible for more than 20% of the total phenotypic variance.

• Journal of the Korean Data and Information Science Society
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• 제26권6호
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• pp.1479-1494
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• 2015

최적의 포트폴리오를 선택하기 위한 연구는 평균-분산모형을 시작으로 다양하게 진행되어 왔다. 과거에는 위험자산의 확률분포가 정규분포를 따른다고 가정하여, 투자자가 보유한 위험자산의 분산이 최소화되고 기대수익률이 최대가 되도록 포트폴리오를 구성하도록 하였다. 그러나 실제 위험자산의 분포에는 극단적인 사건들이 많이 발생하기 때문에 정규분포보다 훨씬 꼬리부분이 두꺼우며, 또한 왼쪽꼬리와 오른쪽꼬리가 대칭적이지도 않은 것으로 밝혀졌다. 이에 본 논문에서는 위험자산의 확률분포를 극단치 이론에서 널리 사용되는 일반화 파레토분포 (GPD)로 모형화하였고 체계적인 위험의 추정을 위하여 VaR를 이용하는 한편, 최적의 포트폴리오의 탐색을 위해서는 유전자 알고리즘을 사용하였다. 제안 방법의 적정성을 확인하기 위해 국내 증시에서 최적 포트폴리오를 탐색해 보았으며, 그 결과 GPD로 투자자산의 위험을 추정하였을 때 가장 좋은 결과를 얻을 수 있었다.