유전 및 육종 : 한우 씨수소의 근교계수와 유효집단크기의 추정

당창권 ( Chang Gwon Dang ),이중재 ( Jung Jae Lee ),김내수 ( Nae Soo Kim ) 한국동물자원과학회(구 한국축산학회) 2011 한국축산학회지 Vol.53 No.4

본 연구는 지금까지 보증 및 후보씨수소로 선발된 씨수소에 대하여 연도별 평균 근교 및 혈연계수를 추정하고 씨수소의 유효집단크기를 추정하여 현재 한우개량 체계의 문제를 도출하여 발전된 대안을 제시하고자 실시하였다. 분석에 이용된 자료는 한우개량사업소로부터 1983년부터 2008년까지 1,128두의 당?후대검정 씨수소자료와 한국종축개량협회로부터 3,760두에 대한 혈통자료를 받아 이용하였다. 보증 및 후보씨수소의 평균 근교계수는 0.04에서 0.97%의 분포로 추정되었으며, 평균 혈연계수는 0.10에서 6.82%의 분포로 추정되었다. 유효집단 크기는 1983년부터 2008년까지 26년간 평균 근교비율을 이용하였을 때 220두로 추정되었다. 근교수준은 최근 2년간 급격히 증가하였고, 평균 혈연계수 역시 점차 증가하는 추세이다. 유효집단크기도 최근 5년의 근교비율로 추정하였을 때 47두로 작게 추정되었다. 보증씨수소 선발시 후대검정우의 도체성적에 의한 유전능력평가 자료의 활용뿐만 아니라, 근교 및 혈연계수를 고려하고 한우의 유전적 다양성의 보존과 근교를 피하기 위하여 현행의 보증씨수소 두수를 증가시켜 유효집단크기를 높여야 될 필요성이 있다고 사료된다. This study was carried out to estimate average inbreeding coefficients, relatedness and effective population size of breeding bulls and to suggest optimal alternatives on problems of current Hanwoo improvement system. Data on proven and young bulls were obtained from 1,128 heads of Livestock Improvement Main Center from 1983 to 2008. Pedigree information on proven and young bulls was obtained from 3,760 heads of Korea Animal Improvement Association. Average inbreeding coefficients and average relatedness of proven and young bulls were estimated at the range of 0.04-0.07%, 0.10-6.82%, respectively. Effective population size was estimated for 220 heads from the average rate of inbreeding of last 26 years. Average inbreeding coefficient is rising rapidly for the last two years as well as average relatedness. Effective population size was estimated for 47 heads for the last five years. These results suggest that selection criteria of proven bulls should include not only genetic evaluation of carcass performance from progeny-test, but also inbreeding and relationship coefficients, in order to maintain genetic variability of Hanwoo. In addition, effective population size should be increased by increasing the number of proven bulls.

평창지역 거세출하우 자료를 이용한 유전모수 추정

당창권(Chang-Gwon Dang),김형철(Hyeong-Cheol Kim),장선식(Sun-Sik Jang),이정묵(Jeong-Mook Lee),홍영훈(Yeong-Hun Hong),전기준(Gi-Jun Jeon),연성흠(Seong-Heum Yeon),강희설(Hee-Seol Kang),양보석(Bo-Suk Yang),홍성구(Seong-Koo Hong),이준헌(J 충남대학교 농업과학연구소 2013 농업과학연구 Vol.40 No.4

The objective of this study was to establish genetic evaluation systems with carcass data collected by 68 individual farms from 2007 to 2011 in Pyeongchang area of Kangwon province. All the possible of environment effects were corrected by analysis of variance (ANOVA) to estimate more accurate genetic parameters. Heritabilities and genetic correlations were estimated from carcass data collected from Hanwoo steers(n=10,441) born in Pyeongchang region from 2005 to 2008. Traits evaluated included carcass weight (CWT), eye muscle area (EMA), back fat thickness (BF) and marbling score (MS). As for the mean value and standard deviation for carcass traits, CWT, EMA, BF and MS were 424.5, 92, 13.7 and 5.7. Parameters were estimated using a multiple trait animal model and derivative-free restricted maximum likelihood procedures. Estimated heritabilities for CWT, EMA, BF and MS were 0.30, 0.21, 0.42 and 0.42, respectively. Genetic correlation of CWT with EMA, BF and MS were estimated to 0.24, 0.36 and 0.07, respectively. Genetic correlation of EMA with BF and MS was -0.27 and 0.61, respectively.

Genetic parameters of calving ease using sire-maternal grandsire model in Korean Holsteins

Alam, Mahboob,Dang, Chang Gwon,Choi, Tae Jeong,Choy, Yun Ho,Lee, Jae Gu,Cho, Kwang Hyeon Asian Australasian Association of Animal Productio 2017 Animal Bioscience Vol.30 No.9

Objective: Calving ease (CE) is a complex reproductive trait of economic importance in dairy cattle. This study was aimed to investigate the genetic merits of CE for Holsteins in Korea. Methods: A total of 297,614 field records of CE, from 2000 to 2015, from first parity Holstein heifers were recorded initially. After necessary data pruning such as age at first calving (18 to 42 mo), gestation length, and presence of sire information, final datasets for CE consisted of 147,526 and 132,080 records for service sire calving ease (SCE) and daughter calving ease (DCE) evaluations, respectively. The CE categories were ordered and scores ranged from CE1 to CE5 (CE1, easy; CE2, slight assistance; CE3, moderate assistance; CE4, difficult calving; CE5, extreme difficulty calving). A linear transformation of CE score was obtained on each category using Snell procedure, and a scaling factor was applied to attain the spread between 0 (CE5) and 100% (CE1). A sire-maternal grandsire model analysis was performed using ASREML 3.0 software package. Results: The estimated direct heritability ($h^2$) from SCE and DCE evaluations were $0.11{\pm}0.01$ and $0.08{\pm}0.01$, respectively. Maternal $h^2$ estimates were $0.05{\pm}0.02$ and $0.04{\pm}0.01$ from SCE and DCE approaches, respectively. Estimates of genetic correlations between direct and maternal genetic components were $-0.68{\pm}0.09$ (SCE) and $-0.71{\pm}0.09$ (DCE). The average direct genetic effect increased over time, whereas average maternal effect was low and consistent. The estimated direct predicted transmitting ability (PTA) was desirable and increasing over time, but the maternal PTA was undesirable and decreasing. Conclusion: The evidence on sufficient genetic variances in this study could reflect a possible selection improvement over time regarding ease of calving. It is expected that the estimated genetic parameters could be a valuable resource to formulate sire selection and breeding plans which would be directed towards the reduction of calving difficulty in Korean Holsteins.

Effect of Retinoic Acid on Proliferation and Differentiation of Preadipocytes from Male and Female Pigs

Song, Mi-Yeon,Dang, Chang-Gwon,Chung, Chung-Soo Korean Society of Animal Sciences and Technology 2011 한국축산학회지 Vol.53 No.3

The current study was undertaken to determine the effect of retinoic acid (RA) on proliferation and differentiation of preadipocytes from male and female pigs. The preadipocytes were isolated from new-born male and female pigs by collagenase digestion and washed three times one day after seeding (designated as day 0 of culture). RA was included in the media at various concentratives from day 0 to 2. The cell number was measured on day 2 with hematocytometer after trypsin digestion. Cell differentiation was determined on day 6 by measuring glycerol-3-phosphate dehydrogenase activity. RA (0.1, 1 and 10 uM) showed no effect on proliferation of preadipocytes from both male and female pigs. However, RA significantly decreased differentiation of pig preadipocytes. Degree of differentiation with 0.1 uM, 1 uM and 10 uM of RA treatment was 80%, 41% and 29% respectively, compared with control. Similar inhibitory effect was found in the female pigs; 77%, 28% and 16% respectively. It is interesting that RA treated on cell proliferation stage had no effect on proliferation but had a strong inhibitory effect on differentiation which is happening in the late stage of cell culture.

Comparison of the estimated breeding value and accuracy by imputation reference Beadchip platform and scaling factor of the genomic relationship matrix in Hanwoo cattle

Soo Hyun Lee,Chang Gwon Dang,Mina Park,Seung Soo Lee,Young Chang Lee,Jae Gu Lee,Hyuk Kee Chang,Ho Baek Yoon,Chung-il Cho,Sang Hong Lee,Tae Jeong Choi 충남대학교 농업과학연구소 2022 Korean Journal of Agricultural Science Vol.49 No.3

The effectiveness of genomic selection for milk production traits of Holstein dairy cattle

Lee, Yun-Mi,Dang, Chang-Gwon,Alam, Mohammad Z.,Kim, You-Sam,Cho, Kwang-Hyeon,Park, Kyung-Do,Kim, Jong-Joo Asian Australasian Association of Animal Productio 2020 Animal Bioscience Vol.33 No.3

Objective: This study was conducted to test the efficiency of genomic selection for milk production traits in a Korean Holstein cattle population. Methods: A total of 506,481 milk production records from 293,855 animals (2,090 heads with single nucleotide polymorphism information) were used to estimate breeding value by single step best linear unbiased prediction. Results: The heritability estimates for milk, fat, and protein yields in the first parity were 0.28, 0.26, and 0.23, respectively. As the parity increased, the heritability decreased for all milk production traits. The estimated generation intervals of sire for the production of bulls (L_SB) and that for the production of cows (L_SC) were 7.9 and 8.1 years, respectively, and the estimated generation intervals of dams for the production of bulls (L_DB) and cows (L_DC) were 4.9 and 4.2 years, respectively. In the overall data set, the reliability of genomic estimated breeding value (GEBV) increased by 9% on average over that of estimated breeding value (EBV), and increased by 7% in cows with test records, about 4% in bulls with progeny records, and 13% in heifers without test records. The difference in the reliability between GEBV and EBV was especially significant for the data from young bulls, i.e. 17% on average for milk (39% vs 22%), fat (39% vs 22%), and protein (37% vs 22%) yields, respectively. When selected for the milk yield using GEBV, the genetic gain increased about 7.1% over the gain with the EBV in the cows with test records, and by 2.9% in bulls with progeny records, while the genetic gain increased by about 24.2% in heifers without test records and by 35% in young bulls without progeny records. Conclusion: More genetic gains can be expected through the use of GEBV than EBV, and genomic selection was more effective in the selection of young bulls and heifers without test records.

Validation of Single Nucleotide Polymorphisms Associated with Carcass Traits in a Commercial Hanwoo Population

Sudrajad, Pita,Sharma, Aditi,Dang, Chang Gwon,Kim, Jong Joo,Kim, Kwan Suk,Lee, Jun Heon,Kim, Sidong,Lee, Seung Hwan Asian Australasian Association of Animal Productio 2016 Animal Bioscience Vol.29 No.11

Four carcass traits, namely carcass weight (CW), eye muscle area (EMA), back fat thickness (BF), and marbling score (MS), are the main price decision parameters used for purchasing Hanwoo beef. The development of DNA markers for these carcass traits for use in a beef management system could result in substantial profit for beef producers in Korea. The objective of this study was to validate the association of highly significant single nucleotide polymorphisms (SNPs) identified in a previous genome-wide association study (GWAS) with the four carcass traits in a commercial Hanwoo population. We genotyped 83 SNPs distributed across all 29 autosomes in 867 steers from a Korean Hanwoo feedlot. Six SNPs, namely ARS-BFGL-NGS-22774 (Chr4, Pos:4889229), ARS-BFGL-NGS-100046 (Chr6, Pos:61917424), ARS-BFGL-NGS-39006 (Chr27, Pos:38059196), ARS-BFGL-NGS-18790 (Chr10, Pos:26489109), ARS-BFGL-NGS-43879 (Chr9, Pos:39964297), and BTB-00775794 (Chr20, Pos:20476265), were found to be associated with CW, EMA, BF, and MS. The ARS-BFGL-NGS-22774, BTB-00775794, and ARS-BFGL-NGS-39006 markers accounted for 1.80%, 1.72%, and 1.35% (p<0.01), respectively, of the phenotypic variance in the commercial Hanwoo population. Many genes located in close proximity to the significant SNPs identified in this study were previously reported to have roles in carcass traits. The results of this study could be useful for marker-assisted selection programs.

Growth Bilolgy : Effect of Retinoic Acid on Proliferation and Differentiation of Preadipocytes from Male and Female Pigs

( Mi Yeon Song ),( Chang Gwon Dang ),( Chung Soo Chung ) 한국동물자원과학회(구 한국축산학회) 2011 한국축산학회지 Vol.53 No.3

The current study was undertaken to determine the effect of retinoic acid(RA) on proliferation and differentiation of preadipocytes from male and female pigs. The preadipocytes were isolated from new-born male and female pigs by collagenase digestion and washed three times one day after seeding(designated as day 0 of culture). RA was included in the media at various concentratives from day 0 to 2. The cell number was measured on day 2 with hematocytometer after trypsin digestion. Cell differentiation was determined on day 6 by measuring glycerol-3-phosphate dehydrogenase activity. RA(0.1, 1 and 10uM) showed no effect on proliferation of preadipocytes from both male and female pigs. However, RA significantly decreased differentiation of pig preadipocytes. Degree of differentiation with 0.1uM, 1uM and 10uM of RA treatment was 80%, 41% and 29% respectively, compared with control. Similar inhibitory effect was found in the female pigs; 77%, 28% and 16% respectively. It is interesting that RA treated on cell proliferation stage had no effect on proliferation but had a strong inhibitory effect on differentiation which is happening in the late stage of cell culture.

국내 젖소의 고온스트레스에 따른 유량 및 유성분의 변화

이석현(SeokHyun Lee),최연호(Yunho Choy),당창권(Chang-Gwon Dang),Alam Mahboob,조광현(Kwanghyun Cho) 한국데이터정보과학회 2018 한국데이터정보과학회지 Vol.29 No.1

본 연구는 고온 스트레스가 우유 생산량 및 유성분에 미치는 영향을 조사하기 위하여 실시하였다. 기후에는 온도, 습도, 풍속, 일조량등 다양하지만 온도와 습도를 이용한 온습도지수는 고온스트레스를 평가하고 열부가 (heat load) 의 지표형질로 사용 한다. 기상 자료는 종관기상관측 장비가 설치된 29개지역과 방재기상관측 장비가 설치된 10개의 지역 농가의 검정일자에 해당하는 최고온도 (°C), 평균 상대습도 (%)을 이용한 온습도지수와 최고온도기록을 이용하였다. 농협 젖소개량사업소와 한국 종축개량협회의 2000년부터 2016년 까지 수집 된 검정기록 총 23,947두의 156,956건을 이용하였다. 유량 및 유질에 대한 분산분석 실시한 결과 3개의 모형에서 고려한 환경요인들은 유량 및 유질에서 유의적 차이 (p < 0.001)를 보였다. THI와 최고온도가 증가 할수록 유질은 감소하는 추세를 보였고, 유량에서는 기준점을 초과 후에 감소하는 추세를 보였다. 따라서 국내에서도 젖소는 고온에 취약함에 따라서 추후 젖소의 유전모수 추정치 최고온도 또는 THI을 고려를 하면 고온스트레스 저항성을 증진시키기 위한 선발이 가능 할 것으로 사료된다. The study was conducted to investigate the effect of heat stress on milk production traits. The temperature-humidity index (THI) was used to estimate the degree of heat stress and as an indicator of heat load. The meteorological data corresponding to testday records were collected from 29 and 10 regional weather stations with automated surface observing system (ASOS) and automatic weather system (AWS) installed, respectively. A total of 156,989 test-day records on 23,947 dairy cows, between 2000 and 2016, was collected by two agencies (dairy cattle genetic improvement center and Korea animal improvement association). The analysis of variance estimates among 3 models showed significant differences between all environments and traits (p < 0.001). Results showed that milk fat and milk protein productions were decreasing with both increasing of THI and highest temperatures. However, the milk yield decreased only after a threshold of THI or highest temperature was exceeded. Our results suggested that the use of THI or highest temperature in dairy genetic evaluation could improve heat tolerance ability in Korean Holsteins.

Stories and Challenges of Genome Wide Association Studies in Livestock — A Review

Aditi Sharma,Jun Seop Lee,Chang Gwon Dang,Pita Sudrajad,Hyeong Cheol Kim,Seong Heum Yeon,Hee Seol Kang,이승환 아세아·태평양축산학회 2015 Animal Bioscience Vol.28 No.10

Undoubtedly livestock is one of the major contributors to the economy of any country. The economic value of livestock includes meat, dairy products, fiber, fertilizer etc. Understanding and identifying the associations of quantitative trait loci (QTL) with the economically important traits is believed to substantially benefit the livestock industry. The past two decades have seen a flurry of interest in mapping the QTL associated with traits of economic importance on the genome. With the availability of single nucleotide polymorphism chip of various densities it is possible to identify regions, QTL and genes on the genome that explain the association and its effect on the phenotype under consideration. Remarkable advancement has been seen in genome wide association studies (GWAS) since its inception till the present day. In this review we describe the progress and challenges of GWAS in various livestock species.