• Journal of Animal Science and Technology
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• 제48권2호
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• pp.161-168
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• 2006

Genetic parameters for linear type and composite traits were estimated by using Bayesian inference via Gibbs sampling with a multiple threshold animal model in Holstein cows. Fifteen linear type traits and 5 composite traits were included to estimate genetic variance and covariance components in the model. In this study, 30,204 records were obtained in the cows from 305 sires. Heritability estimates for linear type traits had the estimates as high as 0.28~0.64. Heritability estimates for composite traits were also high, when the traits were assumed to be categorical traits. Final score was more correlated with the composite traits than with the linear type traits.

• 대한간호학회지
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• 제16권2호
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• pp.29-35
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• 1986

The Purposes of this study are for the assessment of anxiety level and for identification for factors relating to the anxiety of the normal Pregnant women who are impendign or entering labor. The State-Trait Anxiety Inventory is used as the measure of anxiety. The results of the study are as follows: 1. The correlation between state-anxiety and trait-anxiety is 0.459 and the linear regression is y(State-anxiety) : 0.251$\chi$(Trait -anxiety)＋29.27. 2. The maternal state-anxiety is not related to the variables of the age, the educational level, the occupation, the prenatal care, parity, show, labor pain and delivery type except for the premature or early rupture of the fetal membranes. 3. The maternal trait-anxiety is not related to the above-mentioned variables.

• Animal Bioscience
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• 제35권3호
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• pp.377-384
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• 2022

Objective: This study was conducted to estimate multi-trait genetic parameters for somatic cell score (SCS), milk yield and type traits in Nigerian Dwarf (ND) goats from the United States. Methods: Data from 1,041 ND goats in the United States with kiddings in 95 herds were used to estimate multi-trait genetic parameters for SCS, milk (MILK), fat (FAT), and protein (PROT) yields, and 14 type traits. An 18-trait mixed linear animal model for lactation mean SCS (Log₂), MILK, FAT, PROT, and 14 type traits was applied. A factor analytic approach (FA1) in ASReml software was used to obtain convergence. Results: Averages for SCS were low (2.85±1.29 Log₂), and were 314±110.6, 20.9±7.4, and 14±4.9 kg, respectively, for MILK, FAT, and PROT. Heritabilities for SCS, MILK, FAT, and PROT were 0.32, 0.16, 0.16, and 0.10, respectively. The highest heritabilities for type traits were for stature (0.72), teat diameter (0.49), and rump width (0.48), and the lowest estimates were for dairyness (0.003) and medial suspensory ligament (0.03). Genetic correlations of SCS with MILK, FAT, and PROT were positive but low (0.25, 0.18, and 0.23, respectively). Genetic and phenotypic correlations between MILK, FAT, and PROT were high and positive (≥0.66). Absolute values of genetic correlations involving SCS with type traits were generally low or no different from zero. Most of the phenotypic correlations involving SCS with type traits were low. No serious unfavorable genetic correlations between milk yield traits and SCS or between milk yield traits or SCS and type traits were found. Conclusion: Genetic variation exists in the ND breed for most studied traits. The development of selection programs based on these estimates may help accelerate favorable multi-trait genetic changes in this breed.

• 응용통계연구
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• 제21권1호
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• pp.19-33
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• 2008

연속 형질(quantitative trait)에 영향을 미치는 유전자를 알아내기 위해 형제 쌍의 자료를 수집하여, 주로 이용되는 Haseman과 Elston (1972)의 최소제곱 회귀검정법으로 분석하는데 이는 단일 형질에 대한 분석법이다. 현실적으로 여러 형질들이 복잡하게 단일유전자 좌위(single locus)와 연관되어 있어 함께 수집하게 되는 경우에는, 이러한 연관된 여러 형질을 동시에 분석하는 유전연관성 검정법(linkage test)이 절실히 필요한 실정이다. Amos 등 (1990)은 주성분(principal component) 선형모형을 이용하여 Haseman과 Elston (1972)방법을 둘 이상의 형질의 다변량 분석법으로 확장시켰다. 그러나 이 검정방법은 통계량의 분포를 알 수 없기에 아직 제 1종 오류가 제대로 통제되지 못하는 문제를 가지고 있다. 본 논문에서는 이러한 다변량 형질 자료의 연관성검정에 있어 단일변량에 대한 비모수 추세검정법을 다변량 자료에 대한 분석법으로 확장시킨 통계량을 사용할 것을 제안한다. Amos 등 (1990)이 제안한 방법과 다변량 추세검정 통계량을 모의실험으로 생성한 연속형 형질자료에 적용하였을 때, 다변량 추세검정 통계량은 Amos 등 (1990) 방법에서의 여러 문제점이 발생되지 않을 뿐만 아니라 모의실험에서 제 1종 오류가 정해진 유의수준에 가까운 것을 확인하였고, 검정적이 더 높음을 볼 수 있었다.

• Asian-Australasian Journal of Animal Sciences
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• 제28권4호
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• pp.476-484
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• 2015

The objective of this study was to estimate genetic and phenotypic parameters for linear type traits, as well as milk yield (MY), fat yield (FY) and protein yield (PY) in 18,831 Holstein cows reared in 495 herds in Brazil. Restricted maximum likelihood with a bivariate model was used for estimation genetic parameters, including fixed effects of herd-year of classification, period of classification, classifier and stage of lactation for linear type traits and herd-year of calving, season of calving and lactation order effects for production traits. The age of cow at calving was fitted as a covariate (with linear and quadratic terms), common to both models. Heritability estimates varied from 0.09 to 0.38 for linear type traits and from 0.17 to 0.24 for production traits, indicating sufficient genetic variability to achieve genetic gain through selection. In general, estimates of genetic correlations between type and production traits were low, except for udder texture and angularity that showed positive genetic correlations (>0.29) with MY, FY, and PY. Udder depth had the highest negative genetic correlation (-0.30) with production traits. Selection for final score, commonly used by farmers as a practical selection tool to improve type traits, does not lead to significant improvements in production traits, thus the use of selection indices that consider both sets of traits (production and type) seems to be the most adequate to carry out genetic selection of animals in the Brazilian herd.

• Animal Bioscience
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• 제34권4호
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• pp.506-515
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• 2021

Objective: Initial consequence of inbreeding is inbreeding depression which impairs the performance of growth, production, health, fertility and survival traits in different animal breeds and populations. The effect of inbreeding on economically important traits should be accurately estimated. The effect of inbreeding depression on growth traits in sheep has been reported in many breeds. Based on this, the main objective of the present research was to evaluate the impact of inbreeding on some growth traits of Iranian Baluchi sheep breed using quantile regression model. Methods: Pedigree and growth traits records of 13,633 Baluchi lambs born from year 1989 to 2016 were used in this research. The traits were birth weight, weaning weight, six-month weight, nine-month weight, and yearling weight. The contribution, inbreeding and co-ancestry software was used to calculate the pedigree statistics and inbreeding coefficients. To evaluate the impact of inbreeding on different quantiles of each growth trait, a series of quantile regression models were fitted using QUANTREG procedure of SAS software. Annual trend of inbreeding was also estimated fitting a simple linear regression of lamb's inbreeding coefficient on the birth year. Results: Average inbreeding coefficient of the population was 1.63 percent. Annual increase rate of inbreeding of the flock was 0.11 percent (p<0.01). The results showed that the effect of inbreeding in different quantiles of growth traits is not similar. Also, inbreeding affected differently on growth traits, considering lambs' sex and type of birth. Conclusion: Quantile regression revealed that inbreeding did not have similar effect on different quantiles of growth traits in Iranian Baluchi lambs indicating that at a given age and inbreeding coefficient, lambs with different sex and birth type were not equally influenced by inbreeding.

• Asian-Australasian Journal of Animal Sciences
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• 제11권5호
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• pp.463-469
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• 1998

Factor analysis was applied as a multivariate statistical technique to official genetic evaluations of type classification traits for 1,265,785 Holstein cows and 10,321 sires computed from data collected between August 1982 and June 1994 in Canada. Type traits included eighteen linear descriptive traits and eight major score card traits. Principal components of the factor analysis showed that only five factors explain the information of the genetic value of linear descriptive traits for both cows and sires. Factor 1 included traits related to mammary system, like texture, median suspensory, fore attachment, fore teat placement and rear attachment height and width. Factor 2 described stature, size, chest width and pin width. These two factors had a similar pattern for both cows and sires. In constrast, Factor 3 for cows involved only bone-quality, while in addition for sires, Factor 3 included foot angle, rear legs desirability and legs set. Factor 4 for cows related to foot angle, set of rear leg and leg desirability, while Factor 4 related to loin strenth and pin setting for sires. Finally, Factor 5 included loin strength and pin setting for cows and described only pin setting for sires. Two factors only were required to describe score card traits of cows and sires. Factor 1 related to final score, feet and legs, udder traits, mammary system and dairy character, while frame/capacity and rump were described by Factor 2. Communality estimates which determine the proportion of variance of a type trait that is shared with other type traits via the common factor variant were high, the highest ${\geq}$ 80% for final score, stature, size and chest width. Pin width and pin desirability had the lowest communality, 56% and 37%. Results indicated shifts in emphasis over the twelve-year period away from udder traits and dairy character, and towards size, scale and width traits. A new system that computes fmal score from type components has been initiated.

• 농업생명과학연구
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• 제50권1호
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• pp.167-178
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• 2016

본 연구는 국내 Holstein 젖소의 유생산 및 선형심사 형질의 유전적 특성을 파악하기 위해 실시하였다. 자료는 2009년 1월부터 2013년 4월까지 분만한 1산차인 Holstein 젖소 10,218두의 능력검정 자료와 유방 및 지제의 선형심사 자료를 이용하였고, 능력검정 자료 및 선형심사 자료는 각각 농협중앙회 젖소개량사업소 및 사)한국종축개량협회에서 수집한 자료이며, 사)한국종축개량협회의 33,436두에 대한 혈통정보를 분석에 활용하였다. 각 형질의 유전모수 추정은 Animal Model에 근거하여 개발 된 WOMBAT package를 이용하였으며, 추정된 유전분산 및 잔차분산을 이용하여 유전력을 계산하였다. 유량(MY), 유지방량(FY), 유단백량(PY), 유지방율(FP), 유단백율(PP) 및 체세포지수(SCS)의 유전력은 각각 0.128, 0.144, 0.100, 0.273, 0.333 및 0.090이었으며, 유방깊이(UD), 유방질(UT), 정중제인대(MS), 앞유방 붙음성(FUA), 앞유두 위치(FTP), 뒷유방 높이(RAH), 뒷유방 너비(RAW), 뒷유두 위치(RTP), 유두길이(FTL), 발굽기울기(FA), 뒤꿈치 깊이(HD), 뼈질(BQ), 옆에서 본 뒷다리(RLSV), 뒤에서 본 뒷다리(RLRV) 및 보행성(LC)에 대해 각각 0.179, 0.066, 0.104, 0.109, 0.127, 0.099, 0.059, 0.069, 0.154, 0.014, 0.010, 0.052, 0.065, 0.175 및 0.031로 추정되었다. MY와 UD, UT, FTP, RAW, FTL, FA 및 RLSV의 유전상관은 각각 0.334, 0.271, 0.445, 0.544, 0.076, -0.281 및 -0.228 이었고, PP와 MS, FTP, RTP, FTL, FA, BQ, RLSV, RLRV 및 LC의 유전상관은 각각 -0.147, -0.182, -0.262, -0.136, 0.355, 0.311, 0.135, 0.233 및 0.143으로 나타났다. 특히, MY는 RAW와 가장 높은 정의상관(0.544)을 나타낸 반면, SCS는 LC와 가장 높은 부의상관(-0.603)을 나타냈다. FP는 대부분의 유방 선형심사형질과 부의상관 관계를 나타낸 반면, FP는 지제 선형심사형질과 정의상관(0.056~0.355) 관계를 나타냈다.

• 농업생명과학연구
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• 제45권6호
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• pp.109-114
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• 2011

본 논문은 한우 거세우의 각 월령별 체중과 18개월 체척, 도체형질에 대하여 출생지, 후대검정차수, 측정일령, 도축일, 도축일령등의 환경효과가 영향을 미치는지 알아 보기위하여 실시하였다. 이 연구에 사용된 자료는 농협중앙회 한우개량사업소에서 2004년부터 2008년까지 후대 검정한 38차에서 47차까지의 거 세우 1,838두의 성장형질과 도체형질 자료를 이용하였고, 성장형질은 18개월령 체척자료와 6개월, 12개월, 18개월, 24개월 체중을, 도체형질은 24개월령 도축성적을 이용하였다. 각 형질에 대한 환경효과 분석을 위해 각 월령별 체중에 대해서는 고정효과를 출생지, 후대검정차수로 하였고 공변량을 측정일령으로 하였다. 도체형질은 도축일을 고정효과로 도축일령을 공변량으로 하였다. 18개월 체척의 경우는 고정효과를 출생지, 후대검정차수로 하였고, 공변량을 18개월 체척측정일령으로 하였다. 분석결과 24개월 체중에서는 출생지 효과가 유의성이 낮은 것으로 나타났다. 도체형질인 도체중, 등심단면적, 육량지수, 등지방 두께는 도축일에 따른 유의적인 차이가 존재하는 것으로 나타났지만 도축일령에 따른 유의적인 차이는 없었다. 근내지방도에 대해서는 도축일령과 도축일 모두 영향을 미치는 것으로 나타났다. 또한 체척형질은 흉심, 고장폭, 흉위에서 출생지 효과는 영향이 없는 것으로 나타났다. 따라서 본 연구결과는 한우 유전평가 모형 설정 시 활용 가능한 것으로 예상된다.

• Asian-Australasian Journal of Animal Sciences
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• 제23권1호
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• pp.1-6
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• 2010

The objectives of this study were to i) investigate genetic performance for linear type traits of individual Holstein dairy cows, especially focusing on comparative traits, and to estimate genetic variances for these traits using actual data, and ii) compare genetic performance and improvement of progeny by birth country of the cows. Linear type traits defined with five comparative traits on this study were general stature composite (GSC), dairy capacity composite (DCC), body size composite (BSC), foot and leg composite (FLC), and udder composite (UDC). These traits were scored from 1 to 6 with 1 = poor, 2 = fair, 3 = good, 4 = good plus, 5 = very good and 6 = excellent. Final scores (FS) were also included in this study. Data used was collected from the years 2000 to 2004 by the Korea Animal Improvement Association (KAIA). Only data of more than five tested cows by herd appraisal date and by sires having more than ten daughters were included to increase the reliability of the data analyses. A total of 30,204 records of the selected traits, which was collected from 26,701 individuals having pedigree information were used. Herd appraisal date, year of age, lactation stage (grouped by month), and time lagged for milking (in hours) were assumed as fixed effects on the model. Animal additive genetic effects considering pedigree relationship and residual errors were assumed with random effects. Year of age at appraisal date was classified from one to nine years of age, assigning the value of nine years of age for animals that were greater than or equal to nine years of age. From our results, the estimate for heritability was 0.463, 0.346, 0.473, 0.290, and 0.430 on GSC, DCC, BSC, FLC and UDC, respectively. The estimate for FS heritability was 0.539. The greatest breeding values for GSC were estimated for Canada, with the breeding values for American lines increasing for 10 years starting in 1989 but tending to decrease after that until 2004. For DCC, the breeding values for American and Canadian lines showed similar patterns until 1999, after which the breeding values for the American lines declined sharply. For BSC, data from Korea, Canada and the USA followed similar trends overall except when the breeding values of the American lines decreased starting in 1999. Overall, the methods used to evaluate genetic performance in this study were acceptable and allowed for the discovery of differences by country of genetic origin, likely due in part to the American use of selection indexes based primarily on milk yield traits until methods for evaluating other traits began to emerge.