• 농업과학연구
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• 제28권1호
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• pp.1-7
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• 2001

RAPDs 분석에 의한 양친의 유전적 유사성 정도가 F1 잡종강세 예측에 효율적으로 이용될 수 있는지 알아보고자 통일형 6 품종(밀양42, IR747, 백운찰벼, 삼강벼, 수원307, 이리356) 간 반이면 교배 F1 15조합을 작성하였다. 양친과 F1을 공시하여 조사한 수량 등 8개의 특성과 RAPDs 분석을 통해 구한 양친의 유전적거리와의 관계를 조사하였다. 120개의 Operon 프라이머를 6개 품종의 DNA 증폭에 이용한 결과 3367개의 밴드가 발생되었으며 이중 168개가 6개 품종 중 1개 이상의 품종에서 변이를 보였다. 6품종간 유전적 거리는 최소 0.157(백운찰벼와 수원 307호 간), 최대 0.383(삼강벼와 이리356호 간)의 분포를 보였다. 잡종강세의 정도는 정조수량(129%), 수당립수(125%), 수장(109%) 등이 높은 잡종강세를 보였고, 유전적거리는 수당립수와 통계적으로 유의한 부의 상관을 보였지만, 정조수량, 천립중 등과는 유의한 상관을 보이지 않았다.

• Asian-Australasian Journal of Animal Sciences
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• 제32권9호
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• pp.1340-1348
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• 2019

Objective: The objectives were to compare variance components, genetic parameters, prediction accuracies, and genomic-polygenic estimated breeding value (EBV) rankings for milk yield (MY) and fat yield (FY) in the Thai multibreed dairy population using five single nucleotide polymorphism (SNP) sets from GeneSeek GGP80K chip. Methods: The dataset contained monthly MY and FY of 8,361 first-lactation cows from 810 farms. Variance components, genetic parameters, and EBV for five SNP sets from the GeneSeek GGP80K chip were obtained using a 2-trait single-step average-information restricted maximum likelihood procedure. The SNP sets were the complete SNP set (all available SNP; SNP100), top 75% set (SNP75), top 50% set (SNP50), top 25% set (SNP25), and top 5% set (SNP5). The 2-trait models included herd-year-season, heterozygosity and age at first calving as fixed effects, and animal additive genetic and residual as random effects. Results: The estimates of additive genetic variances for MY and FY from SNP subsets were mostly higher than those of the complete set. The SNP25 MY and FY heritability estimates (0.276 and 0.183) were higher than those from SNP75 (0.265 and 0.168), SNP50 (0.275 and 0.179), SNP5 (0.231 and 0.169), and SNP100 (0.251and 0.159). The SNP25 EBV accuracies for MY and FY (39.76% and 33.82%) were higher than for SNP75 (35.01% and 32.60%), SNP50 (39.64% and 33.38%), SNP5 (38.61% and 29.70%), and SNP100 (34.43% and 31.61%). All rank correlations between SNP100 and SNP subsets were above 0.98 for both traits, except for SNP100 and SNP5 (0.93 for MY; 0.92 for FY). Conclusion: The high SNP25 estimates of genetic variances, heritabilities, EBV accuracies, and rank correlations between SNP100 and SNP25 for MY and FY indicated that genotyping animals with SNP25 dedicated chip would be a suitable to maintain genotyping costs low while speeding up genetic progress for MY and FY in the Thai dairy population.

• 한방안이비인후피부과학회지
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• 제18권2호
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• pp.1-9
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• 2005

Objectives: The objective of this study is to investigate the correlation between genetic studies on atopic dermatitis. sasang constitution, and sasang constitional study on atopic dermatitis. Methods: We retrieved data on PubMed for the papers of genetic study on atopic dermatitis. And for the papers on genetic study of sasang constitution and sasang constitional study of atopic dermatitis, we referred to papers have reported on domestic medical journal and domestic korean medicine journal. And we investigated correlations among the studies. Results: 1. There are two studies on genetic study on atopic dermatitis. One has been performed to find out genes related to atopic dermatitis by case-control study. The other has been to investigate the correlation between atopic dermatitis and the genes their functions were well-known. 2. Gene study on sasang constitution was performed to observe the distribution of the genes which is related with characteristics of sasang constitution, but there was no significant maldistribution of the genes. 3. There was no correlation between genetic study on atopic dermatitis and genetic study on sasang constitution. Conclusion & Discussion: In the Sasang constitutional study of atopic dermatitis, it seems that further studies on genes related to characteristics of skin, character affecting on behavior, and neurobiological difference among Sasang constitution are required as well as studies on distribution of genes related atopic dermatitis.

• Asian-Australasian Journal of Animal Sciences
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• 제33권9호
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• pp.1387-1399
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• 2020

Objective: The objective of this study was to estimate the genetic parameters and trends for milk, fat, and protein yields in the first three lactations of Thai dairy cattle using a 3-trait,-3-lactation random regression test-day model. Methods: Data included 168,996, 63,388, and 27,145 test-day records from the first, second, and third lactations, respectively. Records were from 19,068 cows calving from 1993 to 2013 in 124 herds. (Co) variance components were estimated by Bayesian methods. Gibbs sampling was used to obtain posterior distributions. The model included herd-year-month of testing, breed group-season of calving-month in tested milk group, linear and quadratic age at calving as fixed effects, and random regression coefficients for additive genetic and permanent environmental effects, which were defined as modified constant, linear, quadratic, cubic and quartic Legendre coefficients. Results: Average daily heritabilities ranged from 0.36 to 0.48 for milk, 0.33 to 0.44 for fat and 0.37 to 0.48 for protein yields; they were higher in the third lactation for all traits. Heritabilities of test-day milk and protein yields for selected days in milk were higher in the middle than at the beginning or end of lactation, whereas those for test-day fat yields were high at the beginning and end of lactation. Genetics correlations (305-d yield) among production yields within lactations (0.44 to 0.69) were higher than those across lactations (0.36 to 0.68). The largest genetic correlation was observed between the first and second lactation. The genetic trends of 305-d milk, fat and protein yields were 230 to 250, 25 to 29, and 30 to 35 kg per year, respectively. Conclusion: A random regression model seems to be a flexible and reliable procedure for the genetic evaluation of production yields. It can be used to perform breeding value estimation for national genetic evaluation in the Thai dairy cattle population.

• Animal Bioscience
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• 제34권9호
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• pp.1451-1459
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• 2021

Objective: The objectives of the study were to evaluate reproductive performance and selection response through genetic trend of community-based breeding programs (CBBPs) of Bonga sheep. Methods: Reproduction traits data were collected between 2012 and 2018 from Bonga sheep CBBPs. Phenotypic performance was analyzed using the general linear model procedures of Statistical Analysis System. Genetic parameters were estimated by univariate animal model for age at first lambing (AFL) and repeatability models for lambing interval (LI), litter size (LS), and annual reproductive rate (ARR) traits using restricted maximum likelihood method of WOMBAT. For correlations bivariate animal model was used. Best model was chosen based on likelihood ratio test. The genetic trends were estimated by the weighted regression of the average breeding value of the animals on the year of birth/lambing. Results: The overall least squares mean±standard error of AFL, LI, LS, and ARR were 375±12.5, 284±9.9, 1.45±0.010, and 2.31±0.050, respectively. Direct heritability estimates for AFL, LI, LS, and ARR were 0.07±0.190, 0.06±0.120, 0.18±0.070, and 0.25±0.203, respectively. The low heritability for both AFL and LI showed that these traits respond little to selection programs but rather highly depend on animal management options. The annual genetic gains were -0.0281 days, -0.016 days, -0.0002 lambs and 0.0003 lambs for AFL, LI, LS, and ARR, respectively. Conclusion: Implications of the result to future improvement programs were improving management of animals, conservation of prolific flocks and out scaling the CBBP to get better results.

• Asian-Australasian Journal of Animal Sciences
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• 제13권1호
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• pp.1-5
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• 2000

Studies on the genetic and environmental effects on M.longissimus thoracis area (MLTA), fat thickness (SFT), rib thickness (RT) and marbling score (MS) were conducted on 21,086 steers and 7,151 heifers of Japanese Brown breed. All carcass traits were affected significantly (p<0.01) by sire, sex and initial year effects. Both of the MLTA and MS of steers were greater than heifers. Their differences were $1.4cm^2$ for MLTA and 0.05 for MS, respectively. Cattle started for fattening in winter tend to have higher of MLTA and MS and thicker of SFT and RT than those in other seasons. MLTA increase from 1987 to 1989 (about $1.9cm^2$) and decrease until 1994 (about $2.4cm^2$) and then increase again up to 1995 (about $1.5cm^2$). MS were nearly equal from 1987 to 1991 (about "1") and then decrease up to 1995 (about "1"). Heritability estimates of MLTA, RT, SFT and MS were ranged from 0.22 to 0.36. Genetic and phenotypic correlations of MLTA, RT, SFT and MS were positive and ranged from 0.05 to 0.62 and from 0.03 to 0.32 except SFT with MLTA was negative (-0.14 and -0.03).

• Asian-Australasian Journal of Animal Sciences
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• 제12권4호
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• pp.506-510
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• 1999

A study was made of the effects of genetic and environmental factors on ultrasonic estimates of carcass traits of Japanese Brown cows. The M. longissimus thoracis area (MLTA), Subcutaneous (SFT) and Inter Muscular (IMFT) Fat Thickness, Rib Thickness (RT) and Beef Marbling Score (BMS) were scanned at the $7^th$ rib by ultrasound. Significant differences between sires, raising place, birth year and season were found for all traits. The heritabilities estimates for sire or Maternal Grand Sire (MGS) on ultrasonic estimates of carcass traits ranged from 0.05~0.14. Genetic and phenotypic correlations among the ultrasonic estimates were positive (0.13~0.88 and 0.24~0.75). Raising place effects were significant for all traits and the differences were between $30.8{\sim}33.5cm^2$ for MLTA and 0.46~0.67 for BMS. Cows born in 1988 tended to have high MLTA, SFT, IMFT and RT but low BMS. Cows born in spring tended to have high MLTA. Cows born in winter or autumn tended to have high BMS. The interaction effects of birth year with birth season were significant for both. MLTA and BMS.

• Asian-Australasian Journal of Animal Sciences
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• 제5권3호
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• pp.567-570
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• 1992

Variance components were estimated for calf daily gain from birth to 45 days of age in small (S), medium (M) and large (L) lines of beef cattle. Analyses involved records collected on 682 (S), 510 (M) and 228 (L) calves in Iowa, USA from 1978 to 1986. Cytoplasmic lines were determined based on the foundation female in the maternal lineage of each animal. Data were analyzed separately by size line using a derivative-free restricted maximum likelihood procedure under an animal model including additive direct (a), additive maternal (m), cytoplasmic lineage effects and covariance (a, m). The heritabilities for direct and maternal, and the cytoplasmic effects, were 0.13, 0.35 and 0.00 for S, 0.14, 0.32 and 0.00 for M, and 0.05, 0.33 and 0.03 for L. Genetic correlations (a, m) for S, M and L were -0.33, -0.57 and -1.00, respectively. The maternal genetic effect was the most important for calf growth between birth and 45 dyas of age and cytoplasmic variances were not important in any line.

• Asian-Australasian Journal of Animal Sciences
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• 제28권3호
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• pp.318-322
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• 2015

In the modern pork industry, selection of high intramuscular fat (IMF) in pigs is necessary to improve pork quality. Ultrasound has been used previously to predict subcutaneous fat thickness and IMF in the longissimus muscles of line pigs and Real-time ultrasound has also been reported as a reliable method for estimating IMF in live pigs. So we estimate the correlation between meat quality traits and IMF percentage to investigate the possibility of utilizing real-time ultrasound technology for predicting IMF percentage in line pigs to improve pork quality. The genetic and phenotypic correlations for chemical intramuscular fat (CIMF) and ultrasound intramuscular fat (UIMF) were estimated to be 0.75 and 0.76, respectively. These results suggest that genetic factors strongly influence meat quality. The genetic and phenotypic correlation between UIMF and CIMF were 0.75, 0.76, respectively. The heritability of UIMF and CIMF were 0.48 and 0.50, respectively. So we concluded that CIMF can be replaced with UIMF and Ultrasound machines can be used to test IMF in live swine. In future, UIMF can be utilized to improve pork quality as an alternative to CIMF.

• Asian-Australasian Journal of Animal Sciences
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• 제28권8호
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• pp.1090-1094
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• 2015

The aim of the study was to select traits that may constitute a prospective criterion for breeding value prediction of young horses. The results of 1,232 starts of 894 four-, five-, six-, and seven-year-old horses, obtained during jumping championships for young horses which had not been evaluated in, alternative to championships, training centres were analyed. Nine traits were chosen of those recorded: ranking in the championship, elimination (y/n), conformation, rating of style on day one, two, and three, and penalty points on day one, two, and three of a championship. (Co)variance components were estimated via the Gibbs sampling procedure and adequate (co)variance component ratios were calculated. Statistical classifications were trait dependent but all fitted random additive genetic and permanent environment effects. It was found that such characteristics as penalty points and jumping style are potential indicators of jumping ability, and the genetic variability of the traits was within the range of 14% to 27%. Given the low genetic correlations between the conformation and other results achieved on the parkour, the relevance of assessment of conformation in four-years-old horses has been questioned.