Recently, with the increase of meat production, high quality and safety of meat have been strongly emphasized by Korean consumers. Marbling in beef has been regarded as an important criterion deciding meat quality in Korea. The purpose of this study was to identify the transcriptional level of insulin-like growth factor-1 (IGF-1) in longissimus muscle samples of 46 Hanwoo. The level of IGF-1 transcripts was measured by real-time polymerase chain reaction (PCR) and molecular connection of IGF-1 was analyzed using the Pathway Studio program (Ver 9.0). Increase of marbling score (MS) induced increase of IGF-1 transcripts level in the muscle and there is a significant correlation (p<0.05) between IGF-1 mRNA expression and MS. The pathway study showed that IGF-1 genes are regulated in insulin, fatty acid synthase, leptin, and corticotrophin releasing hormone. These results suggest that IGF-1 might be used as a useful marker for the improvement of economic traits in Hanwoo.

This research was conducted to estimate the effect of packaging methods on the color and taste-related precursors in Hanwoo (Korean cattle) beef during aging. Following packaging with vacuum (VACP), low oxygen-modified atmosphere (LOMAP; 0% O2/20% CO2/80% N2) or vacuum skin+LOMAP (VSP+LOMAP), the loins and top rounds were aged at 2℃ for 14 days and lipid oxidation (TBARS content), surface color, glucose and lactate contents were measured. TBARS and glucose contents were not different by packaging methods in both loins and top rounds. The a* (redness), b* (yellowness) and C* (chroma) values were higher (p<0.05) in VACP-aged beef as compared to the other beef. Lactate content was significantly higher (p<0.05) in both LOMAP- and VSP+LOMAP-aged beef than in VACP-aged beef at day 14 of aging. These findings suggested that VACP was the most effective in maintaining color stability but LOMAP was more effective in maintenance of some taste-related precursor compared to VACP.

본 실험에서는 2012년부터 2013년까지 월동작물로 재배되는 총체밀에 콩과작물의 혼파재배와 우분시용이 작물의 생산성과 사료가치를 평가함으로써 단위면적당 가축사육 능력을 추정하고자 시험은 분할구 집구로 배치한 3반복으로 주구는 총체밀 단파, 총체밀과 헤어리베치 혼파 및 사료용 완두 혼파를, 세구에는 우분 4수준으로(0, 50, 100 및 150kg N/ha) 시험이 실시되었다. 총체밀의 연간 건물수량은 지역 시험구 비교에서는 경주 시험구가 경산과 영주 시험구보다 높게 나타났으며, 경주 시험구에서 시험구별 단․혼파 비교에서는 헤어리베치 혼파구가 가장 높게 나타났다(p<0.05). 우분 시용수준에 따른 건물은 전 시험구에서 시용수준이 높을수록 증가하였고 ha당 100, 150kg 수준에서 유의하게 높았다(p<0.05). 사료작물의 사료가치 평가에서 조단백질 함량은 콩과작물의 월동이 가능한 시험구에서는 총체밀 단파보다는 콩과 혼파구가 높은 경향으로 나타났다(p<0.05). 경산지역에서 총체밀의 가소화양분총량(TDN) 함량은 사료용 완두구가 가장 높았으나(p<0.05), 총체밀 단파구와 유의적 차이는 나지 않았다. 한우 사육능력은 경주 시험구가 ha당 3.83두로 경산 시험구의 ha당 3.11두, 영주 시험구의 ha당 1.35두 보다 높았으며(p<0.05), 총체밀 단파보다는 콩과 작물혼파구가, 혼파구에서는 헤어리 배치가 높게 나타났다(p<0.05). 이상의 결과를 종합해 볼 때, 경북지역에서 사료가치 증진을 위한 콩과 사료작물 혼파는 겨울철 콩과작물의 월동성을 고려해야 하며, 콩과작물의 월동이 어려운 지역에는 우분을 시용하며, 또한 단위면적당 수량과 단백질 함량 등의 사료가치를 높이기 위해서는 우분 수준을 ha당 100~150kg 시용과 함께 콩과작물을 혼파하는 것이 가축사육 능력 증대를 기대할 수 있으리라 사료된다.

The objective of this study was to determine the effect of the MC1R genotypes of the Chikso (Korean brindle cattle) sires on the coat colors of their offspring. In this study, 15 Chikso sires with known MC1R genotypes were used for breeding in the Gangwon Province Livestock Research Center, the Chungbuk Institute of Livestock and Veterinary Research, and the Livestock Experiment Station, Jeonbuk Institute of Livestock and Veterinary Research from either 2011 or 2012 to 2013. There were 6 sires with E+E+ genotypes and 9 sires with E+e genotypes, and their coat colors were all whole brindle (more than 50 of the body). Among the 90 calves produced in 2011∼2013 or 2012∼2013 from the 15 sires, 50 (55.6%) of them were females and 40 (44.4%) of them were males. Coat colors of the offspring were determined when they reached over 6 months of age. Calves with whole brindle, part brindle, brown and black coat colors were 42 (48.3%), 11 (12.6%), 18 (20.7%) and 16 (18.4%), respectively. Ratio of calves with whole brindle coat color was higher than any other coat colors. Among the offspring with whole brindle color, 20 (41.7%) calves were female and 22 (51.3%) calves were male. By determining the MC1R genotypes of the dams and calves in this study along the family lines, and investigating other genes that may be involved in the coat colors of the Chikso, better breeding system may be established to increase the brindle coat color appearance in the future.

Cell-free fetal RNA has been highlighted as useful tools for the fetal sex determination or other genetic inherent disorder. However, there is no knowledge about the sex determination using cell free fetal RNA in bovine field. Thus, the present study aimed to evaluate the presence of transcripts of DDX3Y, USP9Y and ZRSR2Y genes in maternal plasma of pregnant cows to determine the sex of the fetus using real-time quantitative polymerase chain reaction assay, and verify its accuracy, sensitivity and specificity compared with the molecular testing and the calf sex at birth. Transcripts of USP9Y and DDX3Y genes were expressed in the all plasma of males and females both the control group and the experimental group. However, ZRSR2Y gene was matched up with the molecular testing and the true sex in control group and has an overall accuracy of 82.6%, a sensitivity of 75%, and a specificity of 100% in experimental group. Therefore, these results indicated that real time PCR technique, as a noninvasive and cost-efficient method, is possible to determination fetal sex in the bovine species using circulating cell free RNA in maternal plasma and especially ZRSR2Y gene could be a good candidate for the RNA based sex determination work.

본 연구는 가상의 국내 젖소유전체 데이터를 생성하여 통계분석방법별, 유전력의 크기별, 참조집단 크기에 따라 유전평가의 정확도 변화에 대해 알아보고자 연구를 실시하였다. 모의실험 데이터 생성은 QMSim프로그램을 이용하였으며, 유전력의 크기(0.1, 0.3, 0.5) 및 참조집단의 크기를(420두, 630두, 1,050두) 달리하여 총 9가지 형태의 데이터를 생성하였고 각 형태별 10회 반복 모의실험을 수행하였다. 통계분석방법간 육종가 정확도 비교 결과 표현형정보, 혈통정보 및 유전체 정보를 모두 이용하여 개체의 유전능력을 평가하는 GBLUP이 유전체 정보 없이 분석하는 BLUP방법에 비해 육종가 정확도가 높게 나타났으며, 특히 자신의 표현형 정보를 갖지 않는 검정집단축군에서 통계분석방법간 육종가 정확도의 편차가 크게 나타났다. 검정형질의 유전력에 대한 크기별 육종가 정확도를 비교한 결과 BLUP과 GBLUP에서 모두 유전력이 높을수록 육종가 정확도가 높게 나타났다. 또한 참조집단크기별 육종가 정확도를 비교한 결과 참조집단축군에서 참조집단크기별 차이가 크게 나타나지 않는(0.02 - 0.03) 반면 검정집단축군의 경우 참조집단크기별 육종가 정확도는 0.02 - 0.10로 표현형 정보가 없을 경우 참조집단 크기에 더 크게 영향을 받는 것으로 나타났다. 본 연구결과를 통해 얻어진 결과는 젖소 유전체 선발을 위한 기초자료로 활용될 수 있을 것으로 판단된다.

The objective of this research was to evaluate the changes of water-soluble flavor precursors in loin and top round from Hanwoo (Korean cattle) beef during aging at 2℃ for 14 days. The glycogen, glucose and lactate contents were not significantly influenced by beef parts and aging. Among nucleotide-related compounds, inosine 5'-phosphate (IMP) and inosine contents were significantly (p<0.05) lower in loin compared with top round but hypoxanthine content was not significantly different between beef parts. Moreover, during aging, IMP content significantly (p<0.05) decreased while inosine and hypoxanthine contents significantly (p<0.05) increased. It is concluded that aging highly affected the nucleotide-related compounds among water-soluble flavor precursors in loin and top round from Hanwoo.

The aim of this study was to identify allele variability and frequencies of six microsatellite markers (BM861, INRA124, INRA189, UMN0103, UMN0307 and UMN0504) specific to the Y-chromosome. DNA samples from 147 males of three Korean native and seven exotic cattle breeds were tested. Three (Chikso, Heugu, and Jeju black cattle) Korean native cattle (KNC) breeds showed Bos taurus genotype. In the neighbor-joining tree, based on Nei’s DA genetic distance, ten breeds represented main group. In addition, Bayesian clustering result showed that 3 main clusters are for individual allele variability and frequencies. Moreover, KNC breeds showed differences in genotype with B. taurus type when compared to previous studies. The molecular information of paternal lineage in this study would be useful for the conservation and utilization of three KNC breeds as genetic resources.

We would like to report a case of bovine lymphosarcoma. Parous cattle from a livestock farmhouse were examined for mutinodular masses in the abdominal cavity after slaughter. For clinical signs, animals presented mild leukemic signs but did not have viral or bacterial infection. Grossly, whitish to yellowish smooth masses similar to fat tissue were covered with a thin membrane. A multilobulated mass formed around the arteri, and there was a large quantity of reddish fluid on the cut surface. Histopathologically, a monomor- phic population of lymphocytes was observed along with small amounts of cytoplasm, round nuclei with coarsely granular chromatin, and numerous mitotic figures in the samples. In the tumor lesion, uniformly round cells had invaded with abundant neovascularization. Especially, the immunohistochemical phenotype of tumor cells was posi- tive for anti-CD3 and negative for anti-CD8 and anti-CD20. Therefore, morphological analysis diagnosed the mass as a multinodular bovine lymphosarcoma of T-cell origin with- out any sign of infection by a viral agent.

The objective of this study was to compare the effects of the levels of inbreeding on body weight traits between two breed populations, Hanwoo and Korea Brindle cattle. Birth weight (BW), weaning weight (WW), body weight at 6 months of age (W6) and yearling weight (YW). Records of 1,745 calves (1,513 from Hanwoo, and 232 from Korea Brindle calves) were collected from Livestock Research Institutes in Kangwon, Gyeongbuk and Chungbuk provinces. The least squares means (LSM) and their standard errors for BW, WW, W6 and YW were 25.4±0.1 kg, 81.0±1.8 kg, 146.1±3.7 kg and 291.5±2.4 kg, respectively in Hanwoo calves and 22.6±0.3 kg, 79.9±2.3 kg, 137.6±4.6 kg and 249.3±6.6 kg, respectively in Korea Brindle calves. Pedigree data showed that 14.8% (316 out of 2131) of Hanwoo was inbred and the average inbreeding coefficient was 0.0209 (2.09%). Inbreeding coefficients of ten calves out of 316 total inbred Hanwoo calves were 12.5% or higher, whereas those of the other 306 calves were less than 12.5%. In both breeds, calves were divided into three groups of inbreeding classes - highly inbred group(F≥ 0.125), lowly to medially inbred group(0<F<0.125) and no inbred group(F=0). In Korea Brindle calf populations, 12.2% of the calves observed (57 out of 467 calves) were inbred and the average inbreeding coefficient was 0.1367(13.67%). Forty four calves out of 57 inbred Korea Brindle calves had inbreeding coefficients of 12.5% or higher and the other 13 calves had less than 12.5% of inbreeding coefficients. Average inbreeding coefficient and the number of calves with greater than 12.5% inbreeding coefficient were higher in Korea Brindle calf groups than in Hanwoo calf groups. On the average, body weight growth of Korea Brindle calves was slower than that of Hanwoo calves. This would be due to very small breeding population structure of Korea Brindle cattle as compared to Hanwoo cattle, which would lead to rapid increase in inbreeding coefficients in the population. In conclusion, our study suggests that planned mating system is needed to control inbreeding in Korea Brindle population.

Bovine coat color is decided by the melanocortin receptor 1 (MC1R) genotype mutation and melanogenesis. Specially, in the various cattle breeds, dominant black coat color is expressed by dominant genotype of ED, red or brown is expressed in the frame shift mutation of recessive homozygous e by base pair deletion and wild type of E+ is expressed in various coat colors. However, not very well known about the effected of MC1R genotype mutation on the coat color through family lines in KBC. Therefore, this study were to investigate effect of MC1R genotype mutation on the coat color, and to suggest mating breed system in accordance with of MC1R genotype for increased on brindle coat color appearance. Parents (sire 2 heads and dam 3 heads) and offspring (total : 54 heads) from crossbreeding in KBC family line with the MC1R genotype and phenotype records were selected as experimental animals. The relationship between melanocortin 1 receptor (MC1R) genotypes expression verified by PCR-RFLP, and brindle coat color appearance to the family line of the cross mating breed from MC1R genotype pattern was determined. As a result, 4MC1R genetic variations, E+/E+ (sire 1), E+/e (sire 2 and dam 3), E+/e with 4 bands of 174, 207 and 328 bp (dam 1) and E+/e with 3 bands of 174, 207, 328 and 535 bp (dam 2) from parents (sire and dam) of KBC. However, 3 genetic variations, e/e (24%), E+/E+ (22%) and E+/e (56%) were identified in offspring. Also, brindle coat color expressrated was the e/e with the 0%, E+/E+ with 67% and E+/e with 77% from MC1R genotype in offspring on the cross mating of KBC. Furthermore, when the sire had E+/e genotype and the dam had E+/E+ with the 3 bands or E+/e genotype, and both had whole body-brindle coat color, 62% of the offspring had whole body-brindle coat color. Therefore, the seresults, the mating system from MC1R genotype patterns of the sires (E+/e) and dams (E+/E+ with the 3 bands or E+/e) with brindle coat color may have the highest whole body-brindle coat color expression in their offspring.

This study was carried out to examine a molecular marker system for parentage test in Jeju Black cattle (JBC). Based on the preliminarily studies, we finally selected for construction of a novel genetic marker system for molecular traceability, identity test, breed certification, and parentage test in JBC and its related industrial populations. The genetic marker system had eight MS markers, five indel markers, and two single nucleotide polymorphisms (SNPs; g.G299T and g.del310G) within MC1R gene which is critical to verify the breed specific genotypes for coat color of JBC differing from those of exotic black cattle breeds such as Holstein and Angus. The results showed lower level of a combined non-exclusion probability for second parent (NE-P2) of 4.1202×10-4 than those previously recommended by International Society of Animal Genetics (ISAG) of 5.000×10-4 for parentage, and a combined non-exclusion probability for sib identity (NE-SI) of 2.679×10-5. Parentage analysis has been successfully identified the JBC offspring in the indigenous population and cattle farms used the certified AI semens for production using the JBC-derived offspring for commercial beef. This combined molecular marker system will be helpful to supply genetic information for parentage test and traceability and to develop the molecular breeding system for improvement of animal productivity in JBC population.

This study was designed to evaluate the effect of L-cysteine on sperm characteristics and oocyte cleavage in vitro in Korean native cattle. For this study, the freezing of diluted semen were added with Triladyl containing 20% eggyolk and/or 0, 5, 10 and 20 mM L-cysteine before cryopreservation. The viability in frozen-thawed sperm were estimated by SYBR14/PI double stain, acrosome damage with FITC-PNA, mitochondria intact with Rhodamin123 and hydrogen peroxide(H2O2) level with carboxy-DCFDA by flow-cytometry. The developmental capacity was also assessed with cleavage rates in oocytes fertilized in vitro by frozen-thawed sperm. In results, the sperm viability was significantly increased in 10 mM and 20 mM concentrations of L-cysteine than other groups (p<0.05). In addition, acrosome damage was significantly decreased in 10 mM and 20 mM concentrations of L-cysteine than other groups (p<0.05). The mitochondria intact was also significantly increased in 10 mM and 20 mM concentrations of L-cysteine than other groups (p<0.05). On the other hand, the cleavage rates were significantly increased in 0 mM, 5 mM and 10 mM groups than 20 mM concentration of L-cysteine (p<0.05). The oocyte degeneration of oocytes were significantly decreased in 0 mM, 5 mM and 10 mM groups than in 20 mM L-cysteine group (P<0.05). However, there are no significantly differences among the L-cysteine treatment groups. We suggest that concentration of 10 mM L-cysteine have beneficial impact for sperm cryopreserved in Korean native cattle. This result also could be recommended for artificial insemination program if supported by an improvement in the fertility results and required further study.

Recently, the transgenic animal production technique is very important for the production of bio-parmaceutical as animal bio-reactor system. However, the absence of survival evaluation in vitro produced transgenic embryos has been a problem of the low productivity of transgenic animal because of absent of pre-estimate of pregnancy after transgenic embryos transferred into recipient. Therefore, this study is conducted to improve efficiency of transgenic cattle production by improving the non-surgical embryo transfer (ET) method. Transgenic bovine embryos were produced by injection of feline immunodeficiency virus enhanced green fluorescent protein (FIV-EGFP) lentiviral vector into perivitelline space of in vitro matured MІІ stage oocytes, and then in vitro fertilization (IVF) was occured. Normal IVF and EGFP expressing blastocysts were transferred into recipients. Results indicated that 2 expanded blastocysts (34.7%) transferred group showed significantly (P<0.05) higher pregnancy rate than 1 expanded blastocyst (26.8%) transferred group. In case of parity of recipient, ET to heifer (34.9%) showed significantly (P<0.05) higher pregnancy rate than ET to multiparous recipient (21.2%). However, there are no significant differences of pregnancy rate between natural induced estrus and artificial induced estrus groups. Significantly (P<0.05) higher pregnancy rate was obtained from recipient group which have normal corpus luteum with crown group (34.8%) than normal corpus luteum without crown (13.6%). Additionally, treatment of 100 μg Gn-RH injection to recipient group (38.6%) 1 day before ET significantly (P<0.05) increase pregnancy rate than non- Gn-RH injection to recipient group (38.6%). We also transferred 2 EGFP expressing expanded blastocysts to each 19 recipients, 7 recipients were pregnant and finally 5 EGFP transgenic cattle were produced under described ET condition. Therefore, our result suggested that transfer of 2 good-quality expanded blastocysts to 100 μg of Gn-RH injected recipient which have normal corpus luteum with crown is feasible to produce transgenic cattle.

본 연구는 국내에서 생산된 주요 동계 사료작물인 청보리 및 청호밀 사일리지를 이용하여 거세 한우의 비육후기(25~30개월 령) 용으로 조제된 TMR의 소 체내 이용성을배합사료 및 볏짚으로 구성된 관행 사료와 비교하고자 반추위 누관이 장착된 소 3두를 이용하여 3 × 3 Latin squaredesign 방법으로 실시되었다. 시험동물에는 비육 후기용 배합사료 및 볏짚을 분리 급여하였거나 (대조구) 청보리 사일리지 TMR (BS-TMR) 또는 청호밀 사일리지 TMR (RSTMR)을 급여하였다. 전체 채취시간에 걸쳐 반추위액의pH, 암모니아 농도 및 총 휘발성지방산 농도는 시험사료간 차이가 없었다. Acetate (C2)의 조성 비율은 사료 급여후 1시간에서 청보리 사일리지를 섭취한 처리구 (BS-TMR)에서 낮은 (p<0.033) 값을 제외하고는 대부분의 채취시간에서 시험사료 간 차이가 없었다. Propionate (C3) 및 butyrate조성비율과 C2/C3 비율 역시 모든 채취시간에서 시험사료간 차이가 없었다. 사료 내 주요 성분의 반추위 유효분해율과 전장소화율은 전체 시험사료 간은 물론 BS-TMR과RS-TMR 간에도 차이가 없는 것으로 나타났다. 본 대사시험 결과로 미루어보아 청보리 및 청호밀로 제조된 TMR의급여 가치가 배합사료 및 볏짚의 분리급여와 차이가 없는것으로 여겨진다.

The purpose of the livestock industry is to pursuit economic profits by increasing the economic productivity of livestock. Single nucleotide polymorphisms (SNPs), that is characterized by one variation out of every 1000 polymorphisms, to increase economical benefits in stock breeding has been extensively studied. Particularly, replete number of investigations have been put forward that has associated SNPs of candidate genes with economically important traits such as carcass weight (CW), longissimus muscle area (LMA), backfat thickness (BFT) and marbling score (MS) in beef cattle. Bovine genome sequencing and HapMap projects have provided, millions of SNPs in the cattle genome. However, till date studies related to the association of the SNPs with economic traits in beef cattles are meager. Discovering of SNPs bovine whole genome would certainly be useful genetic assets for the development of SNP marker for economically important traits in beef cattle.

Jeongseon-gun had 892 Korean beef cattle farmers, and had 9,180 Korean beef cattle in September, 2010. Average fed cattle by farm was less than 20 heads. The small scale breeding ratio was higher than the case of Gangwon-do and the average country level. Jeongseon-gun tries to increase the beef cattle to 20,000 in oder to increase farm income. The purpose of the study is to analysis the farmer's intention to the increasing feed scale. Data were collected by questionnaire. Frequency analysis, factor analysis and cluster analysis were used to analyze. In the results of frequency analysis, about 92% respondents were agreed to expand the increasing scale to 20,000 heads. In order to accomplish the goal, about 63% respondents wanted complex for Korean native cattle breeding. About 62% respondents had intention to increase the feeding cattle heads. In the results of factor analysis, four factors were derived as "Government support", "Infrastructure construction", "Brand development" and "Construction logistics system". In the results of cluster analysis, three clusters were derived as "group that does not need support from the government", "group that needs construction of logistics system" and "group that needs support system".