• Animal Bioscience
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• 제37권4호
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• pp.555-566
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• 2024

Objective: This study aimed to assess the genetic parameters and accuracy of genomic predictions for twenty-four linear body conformation traits and overall conformation scores in Korean Holstein dairy cows. Methods: A dataset of 2,206 Korean Holsteins was collected, and genotyping was performed using the Illumina Bovine 50K single nucleotide polymorphism (SNP) chip. The traits investigated included body traits (stature, height at front end, chest width, body depth, angularity, body condition score, and locomotion), rump traits (rump angle, rump width, and loin strength), feet and leg traits (rear leg set, rear leg rear view, foot angle, heel depth, and bone quality), udder traits (udder depth, udder texture, udder support, fore udder attachment, front teat placement, front teat length, rear udder height, rear udder width, and rear teat placement), and overall conformation score. Accuracy of genomic predictions was assessed using the single-trait animal model genomic best linear unbiased prediction method implemented in the ASReml-SA v4.2 software. Results: Heritability estimates ranged from 0.10 to 0.50 for body traits, 0.21 to 0.35 for rump traits, 0.13 to 0.29 for feet and leg traits, and 0.05 to 0.46 for udder traits. Rump traits exhibited the highest average heritability (0.29), while feet and leg traits had the lowest estimates (0.21). Accuracy of genomic predictions varied among the twenty-four linear body conformation traits, ranging from 0.26 to 0.49. The heritability and prediction accuracy of genomic estimated breeding value (GEBV) for the overall conformation score were 0.45 and 0.46, respectively. The GEBVs for body conformation traits in Korean Holstein cows had low accuracy, falling below the 50% threshold. Conclusion: The limited response to selection for body conformation traits in Korean Holsteins may be attributed to both the low heritability of these traits and the lower accuracy estimates for GEBVs. Further research is needed to enhance the accuracy of GEBVs and improve the selection response for these traits.

• 한국초지조사료학회지
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• 제40권3호
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• pp.167-176
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• 2020

The objective of the present study was to determine the best model to describe and quantify the changes in live body weight, height at withers, height at rump, body length and chest girth of Holstein cows raised under Korean feeding conditions for 50 months. The five standard growth models namely polynomial linear regression models, regression of growth variables on the first and second-order of ages in days (model 1) and regression of growth variables on age covariates from first to the third-order (model 2) as well as non-linear models were fitted and evaluated for representing growth pattern of Holstein cows raised in Korean feeding circumstances. Nonlinear models fitted were three exponential growth curve models; Brody, Gompertz, and von Bertalanffy functional models. For this purpose, a total of 22 Holstein cows raised in Korea used in the period from April 2016 to May 2020. Each model fitted to monthly growth curve records of dairy cows by using PROC NLIN procedure in SAS program. On the basis of the results, nonlinear models showed the lower root mean square of error (RMSE) for live body weight, height at withers, height at rump, body length and chest girth (12.22, 1.95, 1.55, 4.04, 2.06) with higher correlation coefficiency (R²) values for live body weight, height at withers, height at rump, body length and chest girth (0.99, 0.99, 0.99, 1.00, 1.00). Overall, the evaluation of the different growth models indicated that the Gompertz model used in the study seemed to be the most appropriate one for standard growth of Holstein cows raised under Korean feeding system.

• Asian-Australasian Journal of Animal Sciences
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• 제24권3호
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• pp.322-329
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• 2011

A whole genome association (WGA) study was conducted to identify quantitative trait loci (QTL) for body conformation traits in Hanwoo cattle. The phenotypes of 497 steers were recorded from the Hanwoo Improvement Center of National Agricultural Cooperative Federation, Seosan, Korea, and analyzed using the Illumina Bovine 50 k SNP chip. A set of 35,987 SNPs that were available in the Hanwoo population was selected from the chip. After adjustments for the effects of year-season of birth, region and sire, phenotypes were regressed on each SNP using a linear regression model. Three hundred nineteen SNPs were detected for the ten conformation traits (p<0.003). For the significant SNPs, stepwise regression procedures were applied to determine best sets of markers. A total of 72 SNPs were selected (p<0.001), for which the sets of 5, 9, 10, 9, 8, 11, 4, 6, 3 and 7 SNPs were determined for height at withers, rump height, body length, chest depth, chest width, rump length, hip width, thurl width, pinbone width and heart girth, respectively. About 7-26% of the total phenotypic variation was explained by the set of SNPs for each trait. QTL for the conformation traits were harbored on most bovine chromosomes (BTAs). Four SNPs with pleiotropic effects on height at withers and rump height were detected on BTAs 3, 4, 6 and 16. A SNP with pleiotropic effects on chest width and rump length was also detected on BTA10. Two QTL regions, i.e. between 87 and 97 Mb in BTA3 and between 41 and 44 Mb in BTA7, were found, in which SNPs were detected for the five and three conformation traits, respectively. The detected SNPs need to be validated in other Hanwoo populations for commercial application to the genetic improvement of conformation characteristics in Hanwoo via marker-assisted selection (MAS).

• Asian-Australasian Journal of Animal Sciences
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• 제15권11호
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• pp.1527-1530
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• 2002

Factor analysis was applied to the phenotypic correlation matrix of 15 linear type traits (scored linearly 1 to 50 points) for 2035 Holstein cows of 38 sires computed from data collected between 1988 and 1992 in Beijing Shuangqiao Farm and Beijing Xijiao Farm. The 15 linear type traits were stature, body strength, body depth, dairy form, rump angle, rump length, rump width, rear leg side view, foot angle, fore udder attachment, rear udder height, rear udder width, udder cleft, udder depth and teat placement rear view. The first four components accounted for 49.1% of the total variance in type scores. Factor 1 reflected strong cows, with deep bodies, with long and wide rumps, and tall in stature. Factor 2 reflected cows with well attached fore udders, wide rear udders and whose udders were supported by strong suspensory ligaments with close teat placement. Factor 3 reflected cows with good dairyness, sickled in the hocks, high rear udders and udder floors above the hocks. Factor 4 reflected cows with sloping rumps from hooks to pins and with steep foot angle. Principal component and factor analyses are useful to clarify the relationships among type traits.

• Journal of Animal Science and Technology
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• 제45권1호
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• pp.23-32
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• 2003

본 연구는 농협중앙회 가축개량사업소와 한우개량단지에서 생산된 비거세 한우 숫소 3,415두의 자료를 이용하여 성장형질과 도체형질에 대한 유전모수를 추정하기 위하여 실시하였다. 본 연구에 이용된 한우 집단은 상반기와 하반기의 두 집단으로 구분하였는데 상반기 집단은 1986년부터 1990년까지 생산된 숫소 1,592두로서 6개월에 검정개시하여 18개월에 종료하였고, 단방식 우사에서 개체관리를 하였다. 하반기 집단은 1991년부터 1996년까지 출생한 1,823두로 10개월에 검정개시하여 22개월에 종료하였고, 군사식 우사에서 사양관리 하였다. 6-12개월과 12-18개월 일당증체량은 상반기 집단의 경우 1.01kg과 0.77kg이였고, 하반기 집단은 0.80kg과 0.95kg으로 하반기 집단에서 보상성장이 일어난 것으로 사료된다. 12개월 및 18개월 체중의 유전력은 상반기 집단의 경우 0.37 및 0.29이었고, 하반기 집단은 0.47 및 0.33이었으며, 6${\sim}$12개월 및 12${\sim}$18개월 일당증체량의 유전력은 상반기 집단에서 0.26 및 0.11이었고, 하반기 집단은 0.33 및 0.22으로 이들 형질의 유전력은 하반기에서 높았다. 상반기 집단의 12개월령 체고, 십자부고, 곤폭 및 흉위에 대한 유전력은 각각 0.30, 0.25, 0.11 및 0.13이었으며, 하반기의 경우 각각 0.53, 0.44, 0.36 및 0.56이었다. 상반기 집단의 18개월령 체고, 십자부고, 곤폭 및 흉위의 유전력은 각각 0.40, 0.22, 0.12 및 0.21이었고, 하반기의 경우 각각 0.45, 0.42, 0.42 및 0.35이었다. 상반기 집단의 냉도체중, 도체율, 배최장근단면적, 등지방두께 및 도체장에 대한 유전력은 각각 0.11, 0.24, 0.25, 0.18 및 0.21이었고, 하반기 집단의 경우 각각 0.32, 0.52, 0.33, 0.51 및 0.58이었으며, 근내지방도의 유전력은 0.31이었다. 상 하반기간 유전상관의 추정치는 12개월 흉위, 18개월 십자부고, 도체중 및 도체율의 경우 0.8 이상이었으나 다른 형질에서의 추정치는 이보다 낮았다.

• Animal Bioscience
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• 제34권4호
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• pp.516-524
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• 2021

Objective: The genetic evaluation of Santa Inês sheep was performed for resistance to gastrointestinal nematode infection (RGNI) and body size using different relationship matrices to assess the efficiency of including genomic information in the analyses. Methods: There were 1,637 animals in the pedigree and 500, 980, and 980 records of RGNI, thoracic depth (TD), and rump height (RH), respectively. The genomic data consisted of 42,748 SNPs and 388 samples genotyped with the OvineSNP50 BeadChip. The (co)variance components were estimated in single- and multi-trait analyses using the numerator relationship matrix (A) and the hybrid matrix H, which blends A with the genomic relationship matrix (G). The BLUP and single-step genomic BLUP methods were used. The accuracies of estimated breeding values and Spearman rank correlation were also used to assess the feasibility of incorporating genomic information in the analyses. Results: The heritability estimates ranged from 0.11±0.07, for TD (in single-trait analysis using the A matrix), to 0.38±0.08, for RH (using the H matrix in multi-trait analysis). The estimates of genetic correlation ranged from -0.65±0.31 to 0.59±0.19, using A, and from -0.42±0.30 to 0.57±0.16 using H. The gains in accuracy of estimated breeding values ranged from 2.22% to 75.00% with the inclusion of genomic information in the analyses. Conclusion: The inclusion of genomic information will benefit the direct selection for the traits in this study, especially RGNI and TD. More information is necessary to improve the understanding on the genetic relationship between resistance to nematode infection and body size in Santa Inês sheep. The genetic evaluation for the evaluated traits was more efficient when genomic information was included in the analyses.

• Journal of Animal Science and Technology
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• 제52권6호
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• pp.467-473
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• 2010

A total of 4,323,781 records for informal 16 primary linear descriptive traits of dairy cows in Holstein breed from 1988 to 2007 in USA were analyzed to estimate adjustment factors for lactation number and stage. While all factors in the model were highly significant (P < 0.01), major influences on linear type traits were due to lactation number and stage. The frequencies of lactation number 1 through 6 were 58.6, 22.0, 11.8, 4.8, 2.1, and 0.8%, respectively. Further, the frequencies of lactation stage were 0.7, 76.9, 15.3, 4.9, and 2.1%, respectively, for springing, early, medium, late, and dry. To adjust 16 linear traits (stature, dairy form, strength, body depth, rump width, rump angle, legs rear view, leg set, foot angle, fore udder, rear udder height, rear udder width, udder support, udder depth, and front teat placement), additive and multiplicative adjustment factors of lactation number (lactations 2 to 4) and stage (springing, medium, late and dry) were estimated with the solutions in the generalized linear model, assigning lactation 1 and stage early as base class. Additive adjustment factors of lactation number ranged from -1.23 to 2.908, while multiplicative factors ranged from 0.853 to 2.207. Further, additive and multiplicative adjustment factors for lactation stage ranged from -0.668 to 0.785, and from 0.891 to 1.154. Application of adjustment factors to 20 randomly sampled sub-data sets produced the results that additive adjustment factors for both lactation number and stage reduced more mean square of lactation number and stage over 16 linear traits than any combination of adjustments, and leaded additive adjustment factors for both lactation number and stage as a choice of methods for adjustment of informal 16 primary linear type traits collected by classifiers of AI studs.

• Journal of Animal Science and Technology
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• 제44권6호
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• pp.643-652
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• 2002

1997년부터 2001년까지 (사)한국종축개량협회의 전국한우능력평가대회에 출품된 642두의 거세한우의 도축 전까지 4회에 걸쳐 주요 10개 부위의 체형 측정치를 조사하여 주성분 분석을 이용하여 체형을 분류하였으며, 각 체형 측정치의 주성분 지수와 도체 형질과의 상관관계를 분석하였으며, 그 결과를 요약하면 다음과 같다. 1. 1차, 2차, 3차 및 4차 체형 측정치의 principal component(이하 P.C) 1의 분산은 각각 7.610, 8.297, 7.269 및 5.739로서 전체분산 중 76.0%, 83.0%, 72.7% 및 57.4%를 나타낼 수 있었고, P.C 1, P.C 2, P.C 3의 합은 전체분산 중 각각 86.69%, 90.49%, 84.62% 및 77.26%를 나타났다. 2. 각 차수별 체형 측정치의 P.C 1의 모든 계수가 양(+)이어서 일반적으로 좋은 체구의 크기를 나타내었으며, 체구의 크기에 가장 크게 영향을 미치는 형질은 흉심(0.328${\sim}$0.339)과 요각폭(0.325${\sim}$0.341)이였다. 또한 P.C 2, P.C 3 및 P.C 4는 각 차수별로 다양하게 나타났다. 3. 1차, 2차, 3차 및 4차 체형 측정치의 주성분 지수들과 도체형질간의 상관계수 추정에서 대부분의 분산을 차지하는 P.C 1은 도체중(0.539${\sim}$0.755), 일당증체량(0.256${\sim}$0.564), 등지방두께(0.227${\sim}$0.280) 및 배최장근단면적(0.187 ${\sim}$0.344)간에 정(+)의 상관을 보였으며, 육량지수(－0.246${\sim}$－0.110)와는 부(－)의 상관을 보였고, 근내지방도(0.066${\sim}$0.099)와는 대부분 유의적인 상관을 보이지 않거나 낮은 상관을 보였고, P.C 2, P.C 3 및 P.C 4는 주성분 지수들의 값에 따라 도체형질과 다양한 상관관계를 보였다. 단일 체형형질과 도체형질간의 상관 그리고 P.C 1의 주성분 지수와 도체 형질과의 상관간에는 큰 차이가 없었다.

• 농업생명과학연구
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• 제46권1호
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• pp.123-131
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• 2012

본 연구는 한우 성장형질간의 상관분석을 통하여 6, 12, 18, 24개월 체중, 일당증체량, 도체형질과 18개월 체형형질간의 성장단계별 형질간의 상관관계를 파악하고자 실시하였다. 분석에 이용한 자료는 농협중앙회 한우개량사업소에서 후대 검정을 실시한 2004년에서 2008년까지의 거세우 1,838두의 체중과 체형형질을 이용하였고 도체형질은 24개월령 도축성적을 이용하였다. 본 논문에서 상관분석은 관측치 상관과 고정효과를 고려한 잔차상관으로 하였다. 도축 전 생체중과 도체중은 0.92의 높은 상관관계를 가지고 있었다. 도체형질에서는 육량지수와 등지방두께 간에 -0.92의 높은 부의 상관을 보였다. 체형형질에서 십자부고와 체고는 0.89로서 높은 상관관계가 있었으며 흉폭과 흉심이 0.73의 상관관계를 나타냈다. 체위 형질간 상관에서 요각폭에 대해 흉심과 흉폭이 각각 0.75, 0.74의 상관을 보였고 곤폭은 요각폭과 0.74의 상관을 보였다. 좌골폭에 대해서는 흉심, 흉폭, 요각폭, 곤폭이 각각 0.73, 0.70, 0.75, 0.75로 정의 높은 상관을 나타냈다. 체장과 도체중간의 관측치상관은 0.48이였고, 흉위는 도체중과 잔차상관이 0.51로 다른 도체형질보다 상관정도가 높게 나타났다. 따라서 본 연구결과는 한우 후대검정우 유전평가시 기초 자료로 활용 가능할 것으로 예상된다.

• Asian-Australasian Journal of Animal Sciences
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• 제27권9호
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• pp.1250-1253
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• 2014

The objective of this study was to estimate the parameters of Gompertz growth curves with the measurements of body conformation, real-time ultrasound longissimus dorsi muscle area (LMA) and backfat thickness (BFT) in Hanwoo cows. The Hanwoo cows (n = 3,373) were born in 97 Hanwoo commercial farms in the 17 cities or counties of Gyeongbuk province, Korea, between 2000 and 2007. A total of 5,504 ultrasound measurements were collected for the cows at the age of 13 to 165 months in 2007 and 2008. Wither height (HW), rump height (HR), the horizontal distance between the top of the hips (WH), and girth of chest (GC) were also measured. Analysis of variance was conducted to investigate variables affecting LMA and BFT. The effect of farm nested in location was included in the statistical model, as well as the effects of HW, HR, WH, and GC as covariates. All of the effects were significant in the analysis of variance for LMA and BFT (p<0.01), except for the HR effect for LMA. The two ultrasound measures and the four body conformation traits were fitted to a Gompertz growth curve function to estimate parameters. Upper asymptotic weights were estimated as $54.0cm^2$, 7.67 mm, 125.6 cm, 126.4 cm, 29.3 cm, and 184.1 cm, for LMA, BFT, HW, HR, WH, and GC, respectively. Results of ultrasound measurements showed that Hanwoo cows had smaller LMA and greater BFT than other western cattle breeds, suggesting that care must be taken to select for thick BFT rather than an increase of only beef yield. More ultrasound records per cow are needed to get accurate estimates of growth curve, which, thus, helps producers select animals with high accuracy.