• Journal of Animal Science and Technology
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• 제64권1호
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• pp.84-96
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• 2022

The current study was conducted to evaluate the effect of calcium-enriched fatty acid supplementation on the growth performance, blood metabolites, intestinal morphology, carcass traits, and nutrient digestibility of broilers subjected to chronic heat stress. A total of 210 one-day-old broiler chicks (40.12 ± 0.25 g) were randomly allocated to one of five dietary treatments, to obtain six replicates per treatment. Broilers were subjected to chronic heat stress from day 21 to day 35, post-hatching, at 34℃ for 9 h per day. The body weight (BW) and feed intake of the experimental broilers were recorded weekly, and the average daily gain (ADG) and feed conversion ratio (FCR) were calculated accordingly. Rectal temperature was measured to compare the basal body temperatures between individuals, and blood samples were collected on days 21 and 35 to evaluate basal body temperature, serum total cholesterol, and the triglyceride content of the broilers. On days 21 and 35, one broiler from each cage (n=6) was euthanized to measure carcass trait parameters, nutrient digestibility in digesta, and intestinal morphology. On days 14, 28, and 35, the broilers fed 2.0% calcium-enriched fatty acids had higher BW (p < 0.05) than those fed the other diets. However, no differences (p > 0.05) were found in the average daily feed intake (ADFI) between dietary treatments over the 35 experimental days. On the other hand, on day 21, post-hatching, the broilers fed the 2.0% calcium-enriched fatty acid diet had improved (p < 0.05) dietary feed efficiencies compared to the other treatments. On day 28, the broilers fed the 5.0% of calcium-enriched fatty acid diet also had higher (p < 0.05) dietary feed efficiencies than those fed with the other dietary treatments. No effects (p > 0.05) on carcass weight, nutrient digestibility, intestinal morphology, or blood parameters were found between broilers fed with dietary treatments. This study demonstrated that the inclusion of an additive, containing 2.0% calcium-enriched fatty acid, to broiler diet could ameliorate the negative growth performance of broilers; and no interaction (p > 0.05) was observed between the calcium-enriched fatty acid and nutrient digestibility, digestive anatomy, blood metabolism, and carcass traits of broilers subjected to chronic heat stress conditions for 35 days post-hatching.

• Journal of Animal Science and Technology
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• 제55권5호
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• pp.351-358
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• 2013

본 연구는 2008년도부터 2010년까지 농협중앙회 한우개량사업소에서 후대검정한 46~50차 한우거세우 882두의 24개월 체척형질 측정자료, 24개월령에 도축하여 조사한 도체형질 판정자료, 생체중(12, 24개월령) 그리고 24개월령에 도축하여 조사한 부분육 형질을 이용하였다. 본 연구는 한우 도체의 각 부위별 생산량과 상관도가 높은 체척형질을 조사하는데 그 목적이 있으며 이를 위하여 성장형질, 도체성적 및 부분육간의 관측치 상관과 환경효과를 고려한 잔차상관을 구하였다. 부분육과 체척간의 상관관계에서 등심은 흉위와 0.74의 높은 정상관을 나타냈고, 사태는 곤폭, 좌골폭과 관측치 상관이 -0.23, -0.27로 나타났다. 갈비는 흉위와 0.80의 높은 정상관이였다. 체척과 도체성적의 상관관계에서는 도체중과 흉위의 관측치 상관과 잔차상관이 각각 0.86, 0.65로 높게 나타났다. 도체형질과 부분육의 상관관계는 도체중과 등심의 관측치 상관과 잔차상관이 각각 0.87, 0.83으로 나타났으며 등심단면적은 등심, 채끝과 각각 0.65, 0.68의 상관을 나타냈다. 부분육간의 상관관계에서는 사태와 양지가 -0.69의 부의 상관을 나타냈다. 소비량이 높은 등심, 안심 및 갈비는 체척형질 중 흉위와의 상관이 높았고 흉위는 도체중과 상관이 높았다. 따라서 흉위가 커질수록 도체중이 증가될 것으로 예상되며 흉위의 개량을 통해 등심, 안심 및 갈비의 생산량이 늘어날 것으로 사료된다. 본 연구의 결과는 다중회귀모형을 이용한 부분육생산량 예측모형을 개발하는데 기초연구로서 활용 가능할 것으로 생각된다.

• 농업생명과학연구
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• 제51권2호
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• pp.117-126
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• 2017

현재 한우 후보씨수소는 당대검정을 거쳐 12개월령 체중의 육종가와 근내지방도의 혈통지수를 근거로 선발이 이뤄진다. 여기서 이용되는 혈통지수는 실제 검정을 통하여 얻은 능력이 아니라 혈통과 KPN의 능력을 근거로 산출한 능력으로써 정확도가 그리 높지 않다. 그리고 후보씨수소에 대한 후대검정은 현재 검정소 검정과 현장 후대검정으로 나뉘어져 있다. 현장 후대검정의 경우 24개월령 도축이 어렵기 때문에 검정소와 현장 후대검정우를 동시에 비교하기는 쉽지 않다. 따라서 본 연구는 이와 같이 12개월령에 측정이 불가한 선발형질과 현장 후대검정우와 검정소 검정우의 도축시기의 차이를 해소하기 위하여 초음파 측정 기술을 적용하여 도체형질 유전능력을 간접적으로 평가 가능한지 파악하기 위하여 수행 하였다. 연구수행을 위하여 2008년도부터 2013년까지 농협중앙회 한우개량사업소 및 한우육종농가에서 수집한 한우 당 후대검정 자료를 이용하였으며 분석형질로는 12개월령 체중, 12 24개월령 초음파 형질(등심단면적, 등지방두께, 둔부지방, %지방함량) 및 도체형질(도체중, 등심단면적, 등지방두께, 근내지방도)을 이용하였다. 초음파 형질에 대한 환경효과 분석을 통하여 차수-측정일-우사-촬영자-판독자를 동기우군으로 하고 측정 시 체중을 공변량으로 한 모형을 토대로 유전모수를 추정하였다. 그 결과 12개월령 및 24개월령 초음파 형질들에 대한 유전력은 각각 0.21-0.43, 0.32-0.47이었으며 12 24개월령 초음파 형질과 대응되는 도체형질이 각각 0.52-0.75, 0.86-0.89로 높은 유전상관을 보이는 것으로 나타났다.

• Asian-Australasian Journal of Animal Sciences
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• 제18권11호
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• pp.1535-1541
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• 2005

Five broiler chicken lines, namely HC, BPB2, CPB2, PB2 and UM1, involving in a selection program and differing in selection intensity and genetic background, were screened for randomly amplified polymorphic DNA (RAPD) polymorphism using 10 selected decamer primers. Nine primers amplified the genomic DNA, generating 200 to 2,500 bp and all detected polymorphism between lines. Out of 74 bands scored using these primers, 34 (50.0%) were found to be polymorphic. The number of polymorphic loci ranged from 3 to 6 with an average of 4.33. Lines differed considerably for within-population genetic similarity estimated by band frequency (WS = 93.55 to 99.25). Between-line genetic similarity estimates based on band sharing as well as on band frequency ranged from 71.35 to 86.45 and from 73.38 to 87.68, respectively. Lines HC and PB2 were the most closely related to the other, while BPB2 and CPB2 appeared to be more distant from each other. The between-line genetic distance based on both band sharing and band frequency revealed the similar trends as for Between-line genetic similarity. Based on BS and BF criteria, BPB2 and CPB2 as well as PB2 and UM1 lines can be merged to launch a new genetic group for further progress in biometrical objectives. A phylogenetic tree, derived using Nei's coefficient of similarity revealed the different pattern of genetic distance between lines.

• Asian-Australasian Journal of Animal Sciences
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• 제22권5호
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• pp.747-755
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• 2009

The feed resource for animals is a major cost determinant for profitability in livestock production enterprises, and thus any effort at improving the efficiency of feed use will help to reduce feed cost. Feed conversion ratio, expressed as feed inputs per unit output, is a traditional measure of efficiency that has significant phenotypic and genetic correlations with feed intake and growth traits. The use of ratio traits for genetic selection may cause problems associated with prediction of change in the component traits in future generations. Residual feed intake, a linear index, is a trait derived from the difference between actual feed intake and that predicted on the basis of the requirements for maintenance of body weight and production. Considerable genetic variation exists in residual feed intake for cattle and pigs, which should respond to selection. Phenotypic independence of phenotypic residual feed intake with body weight and weight gain can be obligatory. Genetic residual feed intake is genetically independent of its component traits (body weight and weight gain). Genetic correlations of residual feed intake with daily feed intake and feed conversion efficiency have been strong and positive in both cattle and pigs. Residual feed intake is favorably genetically correlated with eye muscle area and carcass weight in cattle and with eye muscle area and backfat in pigs. Selection to reduce residual feed intake (excessive intake of feed) will improve the efficiency of feed and most of the economically important carcass traits in cattle and pigs. Therefore, residual feed intake can be used to replace traditional feed conversion ratio as a selection criterion of feed efficiency in breeding programs. However, further studies are required on the variation of residual feed intake during different developmental stage of production.

• Asian-Australasian Journal of Animal Sciences
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• 제23권7호
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• pp.863-866
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• 2010

Myostatin, which is also known as growth and differentiation factor 8 (GDF8), has been reported to act as a negative regulator of skeletal muscle development. Variation in the myostatin gene (MSTN) has been associated with variation in muscularity in certain "meaty" sheep breeds. Polymerase Chain Reaction-Single Strand Conformational Polymorphism (PCR-SSCP) analysis was used to investigate allelic variation in the previously described g+6223G>A single-nucleotide polymorphism (SNP) in the 3' untranslated region (3' UTR) of MSTN. The sheep studied were 79 New Zealand (NZ) Romney lambs derived from a single sire heterozyous for g+6223G>A, which is in itself notable as this polymorphism has not been described previously in this breed. Allelic variation was observed to be associated with an abnormal gender ratio (p = 0.046) in the progeny. The presence of allele A was observed to have an effect (p<0.05) on birth weight, mean loin yield, proportion yield loin and total muscle yield. Allelic variation did not significantly affect mean shoulder yield, leg yield, proportion yield shoulder and proportion yield leg. This preliminary result suggests that while the A allele at MSTN g+6223 appears to improve some valuable traits in NZ Romney sheep, further research is required to understand if and how it may affect other traits.

• Asian-Australasian Journal of Animal Sciences
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• 제21권6호
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• pp.784-788
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• 2008

Studies to detect genes responsible for economic traits in farm animals have been performed using parametric linear models. A non-parametric, model-free approach using the 'expanded multifactor-dimensionality reduction (MDR) method' considering high dimensionalities of interaction effects between multiple single nucleotide polymorphisms (SNPs), was applied to identify interaction effects of SNPs responsible for carcass traits in a Hanwoo beef cattle population. Data were obtained from the Hanwoo Improvement Center, National Agricultural Cooperation Federation, Korea, and comprised 299 steers from 16 paternal half-sib proven sires that were delivered in Namwon or Daegwanryong livestock testing stations between spring of 2002 and fall of 2003. For each steer at approximately 722 days of age, the Longssimus dorsi muscle area (LMA) was measured after slaughter. Three functional SNPs (19_1, 18_4, 28_2) near the microsatellite marker ILSTS035 on BTA6, around which the QTL for meat quality were previously detected, were assessed. Application of the expanded MDR method revealed the best model with an interaction effect between the SNPs 19_1 and 28_2, while only one main effect of SNP19_1 was statistically significant for LMA (p<0.01) under a general linear mixed model. Our results suggest that the expanded MDR method better identifies interaction effects between multiple genes that are related to polygenic traits, and that the method is an alternative to the current model choices to find associations of multiple functional SNPs and/or their interaction effects with economic traits in livestock populations.

• Communications for Statistical Applications and Methods
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• 제16권1호
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• pp.67-74
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• 2009

고품질 한우를 만들기 위해 여러 경제형질에 영향을 주는 유전자 즉 single nucleotide polymorphisms(SNPs)를 규명하려고 한다. 이미 Lee 등 (2008a)에 의해 SNP(19_1)$^*$SNP(28_2)가 등심단면적 (LMA: longissimus muscle dorsi area)에 주요한 유전자로 규명되었다. 여기에 추가로 도체중 (CWT: carcass cold weight)과 일당증체량 (ADG: average daily gain)을 선형 모형에 적용하였으며 또한 상호작용에 더 유리하고 연속형 데이터에도 사용할 수 있는 expanded multifactor dimensionality reduction (expanded MDR)을 이용하여 주요한 SNP를 파악하였다. Expanded MDR 적용결과 등심단면적과 같은 결과인 SNP(19_1)과 SNP(19_1)$^*$SNP(28_2)의 상호작용 형태가 가장 좋은 SNP로 선정되었으며, 최종적으로 SNP(19_1)*SNP(28_2) 마커가 한우의 여러 경제형질에 우수 유전자임을 규명하였다.

• 한국동물위생학회지
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• 제43권2호
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• pp.45-52
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• 2020

A grading system is implemented to evaluate the meat quality of Hanwoo. In the grading system, grade 1++A is the highest grade. Livestock farms breed Hanwoo with good quality feed in order to obtain the highest grade. In this process, the content ratios of muscles in individual regions can be changed. To find out the muscle distribution ratios of Hanwoo steers, grade 1A, 1+A, and 1++A Hanwoo steers were compared with grade 1+A Hanwoo female. Grade 1A Hanwoo steers had higher ratios of shank (SK), brisket and flank (BF), neck chain (NC), and inside skirt (IS) meats and a lower ratio of striploin (SL) meat compared to grade 1+A Hanwoo feamle. Grade 1++A Hanwoo steers had higher ratios of neck (NK) and loin (LN) meats and lower ratios of inside skirt (IS), tenderloin (TL), top round (TR), eye round (ER), bottom round (BR), bottom sirloin triangle (BST), and knuckle (K) meats compared to grade 1+A Hanwoo steers. In comparison between grade 1A and 1++A Hanwoo steers, the ratio of shank (SK) was significantly lower in higher quality meats. If the changes are continuously studied to improve the process so that the ratios of partial meats of the regions highly preferred by consumers can increase, it will contribute to increases in the incomes of livestock farms and enable Hanwoo to grow into a global brand.

• 한국동물생명공학회지
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• 제38권4호
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• pp.268-274
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• 2023

Background: Recently, the single-step genomic best linear unbiased prediction (ssGBLUP) method, which incorporates not only genomic information but also phenotypic information of pedigree, is under study. In this study, we performed a ssGBLUP analysis on a commercial Hanwoo population using phenotypic, genotypic, and pedigree data. Methods: The test population comprised Hanwoo 1,740 heads raised in four regions of Korea, while the reference population used Hanwoo 18,499 heads raised across the country and two-generation pedigree data. Analysis was performed using genotype data generated by the Hanwoo 50 K SNP beadchip. Results: The mean Genome estimated breeding values (GEBVs) estimated using the ssGBLUP methods for carcass weight (CWT), eye muscle area (EMA), back fat thickness (BFT), and marbling score (MS) were 7.348, 1.515, -0.355, and 0.040, respectively, while the accuracy of each trait was 0.749, 0.733, 0.769, and 0.768, respectively. When the correlation analysis between the GEBVs as a result of this study and the actual slaughter performance was confirmed, CWT, EMA, BFT, and MS were reported to be 0.519, 0.435, 0.444, and 0.543, respectively. Conclusions: Our results suggest that the ssGBLUP method enables a more accurate evaluation because it conducts a genetic evaluation of an individual using not only genotype information but also phenotypic information of the pedigree. Individual evaluation using the ssGBLUP method is considered effective for enhancing the genetic ability of farms and enabling accurate and rapid improvements. It is considered that if more pedigree information of reference population is collected for analysis, genetic ability can be evaluated more accurately.