• Journal of agriculture & life science
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• v.46 no.1
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• pp.113-121
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• 2012

A total of 150,624 records of Holstein milk production collected from 2005 to 2009 were analyzed to investigate the effects of two different contemporary group definitions, parity and somatic cell score (SCS). The first definition (H BY S) of contemporary group was milking cows and heifers born in the same year and season. And the second thing (H CY S) was milking cow and heifers that delivered calves in the same year and season. Effects of contemporary group, parity and regression effect on SCS from two models were highly significant sources of variation. Coverage of variation ($R^2$) was somewhat higher in models with H BY S as contemporary group. From multivariate models with H BY S, phenotypic correlation coefficients of milk components were estimated high and positive. However, the phenotypic correlation coefficient between milk yield and SCS was -0.09, which was low enough to evidence no correlation between them. Phenotypic correlation between SCS and butter fat or between SCS and protein were also negligible but negative. From multivariate models with H CY S as contemporary group, phenotypic correlation among milk traits and SCS were similar to the estimates from models with H BY S. However, SCS in these models were lowly but negatively correlated with milk yield, milk protein, butter fat or SNF, and the phenotypic correlation coefficients of which were -0.10, -0.08, -0.08, -0.11, respectively.

• Journal of Animal Science and Technology
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• v.46 no.2
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• pp.145-154
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• 2004

This study was conducted to estimate genetic parameter of Duroc, Landrace and Yorkshire breeds based on the on-farm performance tested records of 57,316 pigs under the supervision of Korean Animal Improvement Association from 1992 to 1999. Genetic parameters were estimated with a multiple trait animal model by using DF - REML. The result obtained in this study was summarized as follow ; The estimated heritabilities of Duroc, Landrace and Yorkshire were 0.46${\sim}$0.65 for the average backfat thickness, 0.28${\sim}$0.31 for loin depth, 0.50～0.60 for percent lean, 0.45${\sim}$0.55 for the average daily gain, 0.38${\sim}$0.50 for age at 90kg, respectively. Phenotypic correlation of average backfat thickness with loin depth, percent lean, average daily gain and age at 90㎏ for the three breeds were -0.12${\sim}$-0.01, -0.81${\sim}$-0.76, 0.34${\sim}$0.46, and -0.41${\sim}$-0.33, respectively. Phenotypic correlation of loin depth with percent lean, average daily gain and age at 90kg were 0.12${\sim}$0.23, 0.03${\sim}$0.21, and -0.17${\sim}$-0.03, respectively. Phenotypic correlation of percent lean with average daily gain and age at 90kg were -0.37${\sim}$-0.26 and 0.26～0.35, respectively. Phenotypic correlation of average daily gain with age at 90kg was -0.97${\sim}$-0.95. The estimated genetic correlation coefficients of average backfat thickness with loin depth, percent lean, average daily gain and age at 90kg estimated for the three breeds were -0.17${\sim}$0.03, -0.79${\sim}$-0.69, 0.24${\sim}$0.45 and -0.41${\sim}$-0.19, respectively. The estimated genetic correlation coefficients of loin depth with percent lean, average daily gain and age at 90kg were 0.11～0.19, 0.23 and -0.30～-0.20, respectively. The estimated correlation coefficients of percent lean with average daily gain and age at 90kg were -0.36${\sim}$-0.13 and 0.10～0.34, respectively. The estimated genetic correlation coefficients of average daily gain with age at 90㎏ was -0.96${\sim}$-0.95.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.12
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• pp.1678-1684
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• 2006

The objectives of this study were to estimate genetic parameters and sire breeding values for average daily gain (ADG) and carcass traits using sire-maternal grandsire model with REML approach, sire model with REML approach, sire model without relationships among sires and with REML and ANOVA approach, and to investigate advantages and disadvantages of these methods. Data were collected from 42,325 Japanese Black steers and heifers finished and slaughtered from 1991 to 2004. Traits analyzed in this study were average daily gain (ADG) during the fattening period, live weight at slaughter (LW), cold carcass weight (CW), estimated lean yield percentage (LYE), longissimus muscle area (LMA), subcutaneous fat thickness (SFT), rib thickness (RT), and marbling score (BMS). Bivariate analyses were also performed to obtain genetic and phenotypic correlation coefficients among traits. Estimated breeding values were obtained from each model, and simple and rank correlations among breeding values from each model were calculated. Estimates of heritability using the four models ranged from 0.25 to 0.31 in ADG, from 0.21 to 0.24 in LW, from 0.23 to 0.27 in CW, from 0.10 to 0.17 in DP, from 0.40 to 0.42 in LYE, from 0.19 to 0.31 in LMA, from 0.31 to 0.34 in SFT, from 0.26 to 0.33 in RT, and from 0.18 to 0.44 in BMS. The differences in heritability estimates using the four models seemed to be feasible in ADG, CW, DP, LMA, RT, and BMS. Genetic correlation coefficients of ADG with CW, SFT, RT and BMS were moderate to high and positive while the genetic correlation coefficients between ADG and LYE was low and negative. Correlation coefficients of BMS with SFT were negligible for both genetic and phenotypic correlations. The correlations of estimates evaluated from sire models with those from sire-maternal grandsire model were not large enough to convincing that breeding values using a sire model were corresponding to those using a sire-maternal grand sire model. If information of maternal grand sires are not available, the sire model with incomplete pedigree information included only sire of sire (Model 2) is optimal among the sire models evaluated in this study.

• Korean Journal of Poultry Science
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• v.27 no.1
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• pp.51-61
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• 2000

This study was conducted to estimate the general production performance, heritabilities, and genetic phenotypic correlations on several economic traits by multiple trait animal model in Korean native chicken. The data were collected from the records of 5,192 pullets produced from 2,029 dams and 250 sires in Daejon Branch, National Livestock Research Institute from April 10. 1994 to February 10. 1997. Body weights of Red Brown (RB), Yellow Brown (YB), Grey Brown (GB) and Black (B) strains were 1,649.9, 1,439.6, 1,455.6 and 1,575.3g at age of 150 days and 1,923.5, 1,689.6, 1,812.4 and 1,924.0g at age of 270 days, respectively. The ranges of coefficient of variation for body weight were 11.52 to 14.02 at age of 150 days and 12.82 to 14.59% at age of 270 days, respectively. The first eggs of RB, YB, GB and B strains were produced at 147.4, 146.5, 151.1 and 152.1 days, respectively and the coefficients of variation were 7.80 to 8.41%. Egg weight at 270 days were 49.7, 47.6, 48.8 and 48.7 g for RB, YB, GB nd B strains, and coefficients of variation were 6.99 to 7.94% . The number of eggs at age of 270days were 75.8, 78.0, 76.7 and 68.8 for RB, YB, GB and B strains, respectively, and coefficient of variations were 23.87 to 29.89%. On heritability estimates in RB, YB, GB and strains body weight were 0.40, 0.10, 0.09 and 0.57 for RB, YB, GB and B strains at age of 150 days, and 0.23, 0.09, 0.38 and 0.24 at age of 270 days were 0.39, 0.47, 0.60 and 0.62, and egg weights at 270 days and age at 1st egg were 0.36, 0.12, 0.38 and 0.26, number of egg production at 270 days were 0.44, 0.36, 0.58 and 0.49, respectively. The genetic correlation coefficients of body weight with the age of first egg, egg weight and number of egg production at 270days were -0.07∼0.67, -0.24∼0.70 and 0.12∼0.41, respectively ; age of first egg with number of egg production at 270days and egg weight were -0.75∼0.91 and 0.34∼0.97 ; and egg weight with number of egg production at 270days were 0.18∼0.68. The phenotypic correlation coefficients of body weight with at age of first egg, egg weight and number of egg production at 270days were -0.01∼0.74, -0.04∼0.72 and 0.25∼0.57 ; age of first egg with number of egg production at 270days and egg weight were 0.26∼0.52 and 0.52∼0.92, respectively ; and egg weight with number of egg production at 270days were 0.34∼0.91.

• Journal of the Korean Society of Tobacco Science
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• v.11 no.2
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• pp.149-155
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• 1989

This study was conducted to obtain the breeding information for the leaf breakdown, and correlation coefficients between leaf breakdown and some agronomic characters in flue-cured tobacco at Taegu Experiment Station, Korea Ginseng & Tobacco Research Institute. NC 95 and NC 2326 were used as parents. The bulk method procedure was used from the F2 to the F4 generations, 54 plants were selected among F4, and 11 lines were selected among 54 F5 which based on high resistance to bacterial wilt compared with NC2326. The entries were composed of parents and 11 F6 advanced lines, and designed in randomized block with 3 replications. Plant seedlings were transplanted in 16 April. The number of breakdown leaf were investigated at flowering stage, 18 June. There were significant difference between NC 95 and NC 2326 for the number of breakdown leaf, number and weight of ground suckers, days to flower, yield and resistance to bacterial wilt, and similar results were appeared among lines. Estimated heritability in the broad-sense ranged from 59.3% to 87.4% for all characters. Most of genetic correlations were higher than phenotypic coefficients between characters. Number of breakdown leaf was positively correlated with days to flower, the number and weight of ground suckers, while it was negative to yield. One line among 11 had few breakdown leaf, low producted ground suckers and high resistance to bacterial wilt. Above results suggest that the number and weight of ground suckers can be use as a selection criterion for leaf breakdown even under the condition without leaf breakdown.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.4
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• pp.245-250
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• 2000

This study was conducted to analyze the responses of some agronomic traits to the different cultural environments and relations among the agronomic traits for selecting sesame varieties with higher cultural stabilities. The indexes for stability parameters measured were coefficient of variability, heritabilities, genetic correlations and path coefficients of agronomic traits according to locations and years in Korea. The heritabilities of agronomic traits showed different by locations and years. Number of seeds per capsule and 1000 seeds weight showed higher heritabilities, but stem length and seed weight per plant showed relatively lower heritabilities. Average heritabilities of some agronomic traits in 1998 were comparatively higher than those of 1999. Of six areas, Jinju area showed biggest coefficient of yield variability in 1998-1999. Iksan and Taegu areas showed higher heritabilities in 1998, but Iksan and Jinju areas showed lower heritabilities in 1999. Genetic correlations were slightly higher than corresponding phenotypic correlations. Stem length showed positive genetic correlation with the number of capsules per plant, and seed weight per plant and the number of capsule per plant showed positive genetic correlation with seed weight per plant. On the analysis of path coefficients, stem length and number of capsules effected highly on grain yield. Great regional variations were observed on the effects of agronomic traits on grain yield. Higher direct effects of stem length on grain yield were observed at Suwon, Chungwon, Taegu, Jinju and Naju areas, but in Iksan area was observed higher direct effect of the number of capsules per plant on grain yield in 1998. In 1999, higher direct effect of stem length on grain yield was observed at Chungwon and Suwon areas. Iksan and Taegu areas were also observed higher direct effect of the number of capsule per plant on grain yield.

• Journal of The Korean Society of Grassland and Forage Science
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• v.43 no.3
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• pp.122-128
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• 2023

The present study was conducted to analyze agronomic characteristics of 8 ecotypes of Arundinella hirta (A. hirta) and the correlation among them. Changes in phenotypic characteristics of 8 ecotypes were measured at equal intervals of time from May to September. Among ecotypes, Jangsoo-1 has the highest plant height (172.33 cm), number of leaves (9.00) and leaf length (55 cm) while the ecotype Youngduk has the highest leaf width (1.57 cm), fresh mass (26.63 g), dry mass (7.06 g), number of spikelets per spike (53.33), amount of seeds per spike (0.74 g) and amount of seeds per 10 spikes (7.23 g). The ecotype Jinju-1 has the shortest plant height (119 cm) and leaf number (6.33), while Okgye-2 has shortest leaf length (30.67 cm), leaf width (0.93 cm), fresh mass (12.60 g), dry mass (3.30 g), spike length (30.33 cm), spikelet per spike (39.67), amount of seeds per spike (0.61 g) and amount of seeds per 10 spikes (6.00 g). Correlation coefficients were estimated among the studied agronomic characteristics which showed positive and significant association with each other. In the present study, the agronomic data collected would be useful to understand the potential of A. hirta as a forage resource and helpful in selecting the high-yielding genetic resource for future forage improvement.

• Korean Journal of Poultry Science
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• v.23 no.1
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• pp.19-26
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• 1996

The present study was conducted to estimate average weights, and corrlation and regression coefficients among various traits of eggs obtained from Korean native and imported chicken. Data were obtained from 360 layers (180 of Korean native origin, and 180 of imported Decalb Brown) between November 8, 1994 to February 8, 1995. The results obtained are summerized as follows : 1. The mean weights of whole egg, yolk, dense white, thin white, and egg shell of native chicken were lighter (P<0.01) than those of Decalb Brown. 2. The coefficients of variability in each egg trait were lower in native chicken than in Decalb Brown, indicating the higher ability of native chicken to adapt to the local environment. 3. The phenotypic correlation coeffcients between whole egg and weights of yolk, dense white, thin white, and eggshell were 0.842∼0.992(P<0.01) in native chicken, and 0.865∼0.985(P<0.01) in Decalb Brown. 4. The average eggshell thicknesses of native and imported Decalb Brown were 362.5 $\mu\textrm{m}$ and 407.9 $\mu\textrm{m}$, respectively. 5. The regression coefficients of most of the traits of eggs from native chicken were lower than those from Decalb Brown layers, suggesting that Korean native chicken should be improved further in various egg traits measured in this study.

• Journal of Sericultural and Entomological Science
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• no.12
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• pp.1-4
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• 1970

The experimental studies were intended to clarify the effects of leaf yield calculations, and also aimed at estimating the correlations between some characters for the selection of desirable stocks of mulberry trees. The analysis of covariances was the variance components procedures in a replicated trial for the varieties, and also it was used to obtain the genotypic, phenotypic and environmental correlations between the eight characters-branch length, node number, branch diameter, branch number per stock, total branch weight, old branch weight, new shoot and leaf weight, and leaf weight, etc. The results obtained are summarized as follows: Phenotypic, genotypic and environmental covariances are shown in Table 1 and phenotypic correlations, genotypic correlations and environmental correlations are shown in Table 2. Genotypic correlations were slightly higher than the corresponding phenotypic correlations between the characters in the varieties, but the variation in values due to the change of environment appeared between the characters. Genotypic correlations between the leaf yield of mulberry trees and other characters indicated that high leaf yield was genetically correlated with six characters namely branch length, node number, branch number per stock, total branch weight, old branch weight and new shoot weight, etc. It was also observed that lower correlations were appeared between the leaf yield and branch diameter, and branch diameter and other all characters studied in both genotypic and phenotypic correlation coefficients.

• Korean Journal of Poultry Science
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• v.24 no.3
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• pp.153-160
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• 1997

This study was carried out to estimate the heritability and genetic correlation for body weight, shank length and shank width at various wk of age in growing Korean pheasant. All the measurements were done from one day to 20 wk of age with 4 wk interval. The heritability estimates for body weight were in the range of 0.54~0.59 for male and of 0.49~0.81 for female from 4 to 20 wk of age. The heritability estimates of male and female were in the range of 0.38~0. 82 and 0.41~0.67 for shank length, and of 0.48~0.88 and 0.49~0.71 for shank width, respectively. Genetic and phenotypic correlation coefficients between the measurements at different ages in each trait of body weight, shank length and shank width were medium to high positive values. Because the estimates of heritabilities and genetic correlations were high, the genetic gain for body weight is expected by either a direct selection or an early selection based on the record of early growing stage.