• Asian-Australasian Journal of Animal Sciences
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• 제30권8호
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• pp.1074-1080
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• 2017

Objective: The growth, carcass and retail cut yield records on 1,428 Hanwoo steers obtained through progeny testing were analyzed in this study, and their heritability and genetic relationships among the traits were estimated using animal models. Methods: Two different models were compared in this study. Each model was fitted for different fixed class effects, date of slaughter for carcass traits and batch of progeny test live measurement traits, and a choice of covariates (carcass weight in Model 1 or backfat thickness in Model 2) for carcass traits. Results: The differences in body composition among individuals were deemed being unaffected by their age at slaughter, except for carcass weight and backfat thickness. Heritability estimates of body size measurements were 0.21 to 0.36. Heritability estimates of retail cut percentage were high (0.56 from Model 1 and 0.47 from Model 2). And the heritability estimates for loin muscle percentage were 0.36 from Model 1 and 0.42 from Model 2, which were high enough to consider direct selection on carcass cutability traits as effective. The genetic correlations between body size measurements and retail cut ratio (RCR) were close to zero. But, some negative genetic correlations were found with chest girths measured at yearling (Model 1) or at 24 months of age or with chest widths. Loin muscle ratio (LMR) was genetically negatively correlated with body weights or body size measurements, in general in Model 1. These relationships were low close to zero but positive in Model 2. Phenotypic correlation between cutability traits (RCR, LMR) and live body size measurements were moderate and negative in Model 1 while those in Model 2 were all close to zero. Conclusion: Therefore, the body weights or linear body measurements at an earlier age may not be the most desirable selection traits for exploitation of correlated responses to improve loin muscle or lean meat yield.

• 한국수산과학회지
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• 제42권6호
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• pp.600-603
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• 2009

Genetic and phenotypic parameter estimates for measurement traits were obtained from pacific oyster Crassostrea gigas at nine months old. For the growth-related traits among nine months old pacific oyster, heritabilities of shell length, shell height, shell width, total weight, body weight and shell weight were estimated as 0.4855, 0.5248, 0.0884, 0.7236, 0.7726 and 0.6957, respectively. Genetic correlations among the growth-related traits of pacific oyster at nines month old, shell length, shell height, shell width, total weight, body weight, shell weight were showing highly positive correlations. Breeding value on growth-related traits of pacific oyster at nine months old were estimated as shell length -7.044-11.870, shell height -11.380-18.370, shell width -1.234-2.831, total weight -8.339-17.140, body weight -1.813-3.507 and shell weight -4.422-8.837. The results show that there is quite substantial additive genetic variance for measurement traits in pacific oyster that can be exploited through selective breeding.

• Asian-Australasian Journal of Animal Sciences
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• 제14권1호
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• pp.1-6
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• 2001

Additive and dominance genetic variances were estimated for purebred Landrace selected with line breeding from 1989 to 1995 at Miyazaki Livestock Experiment Station, Kawaminami Branch. Ten body measurements, two reproductive traits and fifteen carcass traits were analyzed with single-trait mixed model analysis. The estimates of narrow-sense heritabilities by additive model were in the range of 0.07 to 0.46 for body measurements, 0.05 to 0.14 for reproductive traits, and 0.05 to 0.68 for carcass traits. The additive model tended to slightly overestimate the narrow-sense heritabilities as compared to the additive and dominance model. The proportion of the dominance variance to total genetic variance ranged from 0.11 to 0.91 for body measurements, 0.00 to 0.65 for reproductive traits, and 0.00 to 0.86 for carcass traits. Large differences among traits were found in the ratio of dominance to total genetic variance. These results suggested that dominance effect would affect the expression of all ten body measurements, one reproductive trait, and nine carcass traits. It is justified to consider the dominance effects in genetic evaluation of the selected lines for those traits.

• 농업과학연구
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• 제41권3호
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• pp.229-236
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• 2014

This study presents the estimates of heritabilities of body measurement traits and carcass traits, and genetic and phenotypic correlations of those traits for crossbred pigs in Korea. Body and ultrasound (A mode: Piglog 105) measurements in 221 pigs including body weight, length, height and width, three back fat thickness at the points of 4th, 14th rib and chine bone, eye muscle area and lean meat percent were collected at the ages of 70, 145 and 180 days and then slaughtered to measure carcass weight, back fat, belly, collar butt, spare rib, picnic shoulder, hind leg, loin, tenderloin, lean meat yield and intramuscular rough fat content in loin. Genetic analysis was done using a multi-trait animal model. Heritabilties of the body measurements were ranged from 0.331 to 0.559 and three measurements of back fat thickness were also high as range varying from 0.402 to 0.475 for the ages of 145 and 180 days. However, eye muscle area was moderate (0.296) at the age of 180 days. Heritabilities of retail cut yields were also high as ranged from 0.387 to 0.474 and of IMF content in loin was 0.499. Heritabilities of the cut percent traits were ranged from 0.249 to 0.488. Important positive genetic and phenotypic correlations were noted for all carcass yield traits (0.298 to 0.875 and 0.432 to 0.922, respectively). IMF showed low negative genetic correlations with carcass yield traits, such as carcass weight, picnic shoulder, hind leg, loin, tenderloin and lean meat yield whereas low positive genetic correlations with back fat, belly, collar butt and spare rib. Loin, tenderloin and lean meat percent showed negative genetic correlations with carcass weight, back fat thickness, collar butt, spare rib and picnic shoulder percent. The four body measurements at the ages of 70, 145 and 180 days had positive genetic correlations with belly, shoulder butt, spare rib, picnic shoulder and hind leg percent, but negative genetic correlations were shown with loin and tenderloin percent except body measurements at 70 days. The results suggest that carcass yield are negatively correlated with intramuscular fat content, which is a major factor deciding pork quality and the yield of loin and tenderloin are not increased as much as increase in body size. However, the proportions of belly and collar butt are increased with the body size. In conclusion, selection strategy should be designed according to the preference on composition of carcass in each country.

• Journal of Animal Science and Technology
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• 제50권6호
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• pp.763-774
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• 2008

본 연구는 한우의 체형형질이 도체형질에 어떤 영향을 미치는지 알아보기 위하여 실시하였다. 본 연구는 농협중앙회 한우개량사업소에서 1997년부터 2002년도에 후대검정(24개월령)한 거세우 1,312두의 체형형질과 도체형질의 자료를 이용하였다. 체형형질은 18개월령 체형측정치를 이용하였고 도체형질은 축산물등급판정소 등급판정결과를 이용하였다. 본 연구의 결과를 정리해보면 도체중과 18개월령의 체중, 체고, 흉폭에서 각각 0.690, 0.483, 0.506으로 나타났고, 배최장근단면적과 18개월령의 체중, 흉폭에서 각각 0.356, 0.279로 나타났다. 이는 체중과 체고, 흉폭의 개량을 통해서 배최장근단면적의 넓이를 넓게 하면 육량을 증대시키는 효과가 있을 것으로 사료되어진다. 다만, 육량지수와 체형형질 사이에 나타난 부의상관관계에 대한 부분은 고려되어야 할 것으로 사료되어지며 개량방향 설정에 있어 등지방의 두께를 줄일 수 있는 방안을 모색해야 할 것으로 사료되어진다. 농가 소득 증대를 위해서는 육질개량뿐만 아니라 육량의 증대 또한 중요한 요인으로 작용한다. 본 연구의 결과에서 알 수 있듯이 체중, 체고와 흉폭의 개량에 힘쓰고 나머지 체형형질의 개량도 지속적으로 이루어져야 할 것으로 사료되어진다. 체형형질에 대한 더 많은 연구가 이루어져 보다 명확한 결과를 얻어야 할 것이고 이는 한우 체형의 개량에 많은 도움이 될 것이다.

• 한국수산과학회지
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• 제54권6호
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• pp.974-981
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• 2021

The aim of this study was to evaluate genetic parameters of growth traits for improving selective breeding in olive flounder Paralichthys olivaceus produced in April 2019. The total length and body weight at 11-, 18-, and 22-months-old were measured for 7,479, 2,831 and 1,904 individuals, respectively. Since 2004, we have been conducting a selective breeding program to improve growth traits in the olive flounder. Data were analyzed using the restricted maximum likelihood method using the multiple traits animal model. The effect of sex and production period showed significant differences in all traits (P<0.05). The heritability of all traits was 0.428-0.520, which is relatively high by measurement month. Therefore, it is considered that individual selection will be more advantageous than family selection. However, to maintain an appropriate degree of inbreeding and genetic diversity for future generations, it is necessary to consider family selection adequately. Results of the correlation analysis between the same traits according to the measurement period indicated that considering production costs such as feed cost, selection at 18-months-old will be advantageous. Olive flounder is a major aquaculture species in Korea, and continuous selective breeding research is essential to improve productivity.

• 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.

• Asian-Australasian Journal of Animal Sciences
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• 제19권4호
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• pp.468-474
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• 2006

Real time ultrasound data was generated on 10,596 live Hanwoo cows to study genetic variation on ultrasonic beef quality traits and to assess the best model to estimate genetic parameters on these traits. Pedigree stacking and data validation was done using the SAS statistical software and the genetic parameter estimates were obtained by EM-REML algorithm. Out of the five different multi-trait mixed animal models constructed, the optimal model included fixed effects of herd, year-season-appraisal, body condition score, linear and quadratic covariates for chest girth, the linear covariate effect of age and the random animal and residual effect of the five models studied. The heritability of longissimus muscle area (LMA), $12^{th}$ rib measurement of back fat thickness (BF) and marbling score (MS) was 0.11, 0.17 and 0.15, respectively. Genetic correlation of LMA vs. BF, LMA vs. MS and BF vs. MS was -0.15, 0.06 and 0.61, respectively. The results showed presence of genetic variation in these ultrasonic beef quality traits in Hanwoo cows and suggest that the selection of Hanwoo cows may be possible by performing ultrasonic scans on live animals, which will ultimately be helpful in reducing the generation interval and the cost of selection procedure.

• Journal of Animal Science and Technology
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• 제55권5호
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• pp.373-380
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• 2013

본 연구는 한우의 생체상태에서 부분육 생산량 예측모형을 개발하고자 실시하였다. 농협중앙회 한우개량사업소에서 후대 검정한 한우 거세우 874두의 24개월령에 측정된 체척자료를 통하여 24개월령에 도축된 부분육 중량과 수율을 예측하는 모형을 발굴하였다. 부분육은 대분할 중량과 수율을 이용하였으며, 부분육 수율은 도체중 대비 생산량으로 구하였다. 부분육 형질에 영향하는 환경효과 분석을 위하여 범주형 변량과 공변량을 각각 도축일, 도축일령으로 하였다. 분산분석 결과 부분육 중량과 수율 모두 도축일 효과가 유의하였으며 (P<0.01), 도축일령 효과는 우둔중량만 유의성 (P<0.05)을 나타냈다. 상관분석 결과에서는 안심, 등심 및 갈비의 중량은 흉위와 각각 0.54, 0.74 및 0.80의 높은 상관관계를 나타냈으므로 흉위가 커지면 선호도가 높은 안심, 등심 및 갈비의 중량도 증가될 것으로 사료된다. 등지방두께는 갈비를 제외한 모든 부분육 수율과부의 상관관계 (-0.22~-0.44)를 나타냈다. 안심의 수율은 체고(0.07), 십자부고 (0.07)를 제외한 나머지 체척형질들과 부의 상관관계를 나타냈으며, 등심의 수율은 흉폭 (0.03), 고장 (0.06), 곤폭 (0.03)을 제외한 나머지 체척형질들과 부의 상관을 나타냈다. 갈비의 수율과 흉위는 0.21의 정의 상관을 나타냈다. 부분육 생산량 예측을 위한 회귀모형에서 설명변량으로 10개의 체척 값을 이용하였다. 회귀분석은 회귀식의 유의성이 인정되는 범위에서 회귀모형의 적합도를 나타내는 결정계수의 값이 가장 높고 $C_p$ 값이 가장 적은 시점에서 변수를 선택하였으며, 분석결과 10가지의 체척치 중 체고, 체장, 고장, 좌골폭 및 흉위가 안심과 등심의 생산량 예측에 중요한 형질인 것으로 나타났다. 특히 흉위는 모든 부분육 중량을 추정하는 회귀식에 설명변량으로 선택이 되었다.

• Animal Bioscience
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• 제34권2호
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• pp.185-191
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• 2021

Objective: The objective of this study was to estimate the genetic parameters for worm resistance (WR) and associated characteristics, using the linear-threshold animal model via Bayesian inference in single- and multiple-trait analyses. Methods: Data were collected from a herd of Santa Inês breed sheep. All information was collected with animals submitted to natural contamination conditions. All data (number of eggs per gram of feces [FEC], Famacha score [FS], body condition score [BCS], and hematocrit [HCT]) were collected on the same day. The animals were weighed individually on the day after collection (after 12-h fasting). The WR trait was defined by the multivariate cluster analysis, using the FEC, HCT, BCS, and FS of material collected from naturally infected sheep of the Santa Inês breed. The variance components and genetic parameters for the WR, FEC, HCT, BCS, and FS traits were estimated using the Bayesian inference under the linear and threshold animal model. Results: A low magnitude was obtained for repeatability of worm-related traits. The mean values estimated for heritability were of low-to-high (0.05 to 0.88) magnitude. The FEC, HCT, BCS, FS, and body weight traits showed higher heritability (although low magnitude) in the multiple-trait model due to increased information about traits. All WR characters showed a significant genetic correlation, and heritability estimates ranged from low (0.44; single-trait model) to high (0.88; multiple-trait model). Conclusion: Therefore, we suggest that FS be included as a criterion of ovine genetic selection for endoparasite resistance using the trait defined by multivariate cluster analysis, as it will provide greater genetic gains when compared to any single trait. In addition, its measurement is easy and inexpensive, exhibiting greater heritability and repeatability and a high genetic correlation with the trait of resistance to worms.