The role of Fatty acid binding protein 4 (FABP4) gene is critical for lipid metabolism and for maintaining homeostasis in adipocytes. Association between Hanwoo carcass traits and FABP4 gene g.7516G>C SNP has been reported previously, however, its association and how does it influence Korean brindle and black cattle has not been demonstrated and established till date. For this purpose, the study was planned to analyze the SNP association (Single Nucleotide Polymorphism) (g.7516G>C) in FABP4 gene and gather genetic information on economic traits of Korean brindle cattle and black cattle. As per sequence of bovine FABP4 gene available (Genbank accession No. NC_007312.4), one pair of primers (5’-ATA TAG TCC ATA GGG TGG CAA AGA-3’ and 5’-AAC CTC TCT TTG AAT TCT CCA TTC T-3’) was designed to amplify a 452bp product of the FABP4 gene including the region of 7417–7868. The SNP, detected by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) methods using restriction enzyme MspA1I, was genotyped in 117 animals of brindle cattle and 24 animals of black cattle population. Statistical analysis revealed that the FABP4 genotype significantly (p<0.05) affect with carcass weight, but there was no significant association with any other economic traits was observed in brindle as well as in black cattle. In conclusion, these results suggested that SNP (g.7516G>C), located in FABP4 gene, could be used as important DNA marker of economic traits in Korean brindle cattle. Furthermore, we suggest that additional samples needs to further analysed to make related data exclusively authentic.

The melanocortin receptor type 4 (MC4R) gene is expressed in the hypothalamus and regulates energy intake and body weight. Recently, it has been reported that obesity and energy balance in human were also regulated by the MC4R gene. Therefore the objective of this study was to identify the polymorphism on the MC4R gene SNP C1786T and its association with economic traits in Korean native cattle (brindle and black cattle) by PCR-RFLP. A total of 125 cattle from the two breeds were tested for economic traits (meat quality index, backfat, thickness, carcass weight, longissimus muscle area and marbling score) and data was analyzed using SAS program. In the results, C allele had highest frequency than G allele frequency in the both breeds and the gene was significantly associated with meat quantity index and backfat thickness in brindle cattle breed. However, in black cattle, the gene was significantly associated with longissimus muscle area (p<0.05). These results suggest that C1786T SNP of the MC4R gene may be useful as a genetic marker for economic traits in the brindle and black cattle.

The objective of this study was to evaluate several types of uterine bacteria in Hanwoo. uterine bacteria from randomly selected 5 uterus was collected by flushing methods into a sterilized 1.5 ml centrifuge tube and was inoculated onto MacConkey agar and blood agar, respectively. After being incubated for 5% CO2, aerobic or anaerobic condition at 37℃ during 48h, bacterial colonies were selected and re-inoculated onto blood agar plates. Re-cultured colonies were identified by Gram staining and finally identified using Vitek system. The identified bacteria were Staphylococcus lentus, Staphylococcus sciuri, Staphylococcus vitulinus, Staphylococcus warneri of Gram (+) and Rhizobium radiobacter, Sphingomonas paucimobilis of Gram () bacteria. Although, pathogenicity of identified bacteria was unclear, the bacteria can have an effect on the uterine microenvironment. Therefore, repetitive research will be required to determine the effects of bacteria in cattle exposed to a various environment.

Solution of glycerol, ethylene glycol, sucrose, dextrose (GESD) and cryotop methods were carried out to investigate the survivability on vitrification of embryos. Embryos cultured in vitro were vitrified by GESD of 10 or 8 step and cryotop methods of 6 step, from cryopreservation step to frozen-thawed and culture step. Survival rate and ICM, TE cells of embryos were investigated after frozen-thawed 24 h. As a results, cryotop method was significantly (p<0.05) higher ( vs. , ) than GESD 10 or 8 step methods on survivability. Also, In ICM cell number, cryotop method was significantly (p<0.05) higher to cells than GESD 8 step method. TE cell number was significantly (p<0.05) highest to cells in cryotop method. On the other hand, survival rate, TE and total cell number were all the significantly (p<0.05) high, except ICM in GESD 10 step method between GESD 10 step method and GESD 8 step method. In conclusion cryotop method was to be most effective, but it is considered necessary to study vitrification method for step-by-step freezing and thawing process.

This study was carried out to effects of ethylene glycol concentration, sucrose and culture day of in vitro production embryo on slow-down freezing in Hanwoo. 6, 7, 8 and 9 day embryos produced in vitro were frozen using 1.8M EG+0.1M sucrose, 1.8M EG+0.5% BSA and 1.5M EG+0.1M sucrose media. Survivability was confirmed after frozen-thawed 24 and 48h and ICM, TE cell number were counted by Hoechst 33342 and PI staining after frozen-thawed 24h. As a result, 1.8M EG+0.1M sucrose group was most significantly (p<0.05) higher compared with the other treatment groups on survivability, TE and total cell number after frozen-thawed 24h (, and ). ICM number did not found significant (p<0.05) differences between the three treatment groups. in 6, 7, 8 and 9 day of embryos using three types of freezing media, frozen-thawed, 1.8M EG+0.1M sucrose groups with embryos cultured 8 day was significantly (p<0.05) highest survivability to after frozen-thawed 24h. 1.5M EG+0.1 sucrose group with embryos cultured 9 day was significantly higher survivability than group of embryos cultured 8 day after frozen-thawed 24 and 48h. In conclusion, 1.8M EG+0.1M sucrose media is considered to be effective to cryopreservation of embryos cultured 8 and 9 day.

This study was conducted to investigate the effect of age on the oxidative stability of Hanwoo (Korean cattle) cow beef. The samples of M. longissimus dorsi from 65 and 133 months-old-Hanwoo cows (4 and 3 heads, respectively) were stored at 4±0.2℃ for 9 days. The proximate composition, total myoglobin content, pH value, water-holding capacity and drip loss were not significantly affected by age. At day 9 of storage, the lipid oxidation (2-thiobarbituric acid reactive substances) was significantly (p<0.05) higher in beef from 133 months-old-cows than 65 months-old-cows. Lower (p<0.05) oxymyoglobin concentration and R630-R580 value and higher (p<0.05) metmyoglobin concentration were observed in beef from 133 months-old-cows at day 9 of storage than 65 months-old-cows. The CIE a*, b* and C* values were significantly (p<0.05) lowered in beef from 133 months-old-cows at day 9 of storage than 65 months-old-cows. It could be concluded that old age decreased the lipid oxidation stability and myoglobin oxidation stability in Hanwoo cow beef.

본 연구는 논에서 조사료 생산을 위한 총체벼와 총체 영양보리 이모작 그리고 수수 수단그라스 교잡종과 총체 영양보리 이모작 재배시 우분액비 시용에 따른 총체 벼, 총체 영양보리, 수수 수단그라스 교잡종의 생산성, 사료가치, 토양성분 및 용탈수중의 무기물 농도를조사하였다. 본 연구는 2006년 5월부터 2009년4월까지 3년 동안 전라북도 김제군 백산면 시험포장에서 완전임의배치 3반복으로 수행되었다. 총체 벼의 후작으로 재배된 총체 영양보리의 2년간 평균 수량은 7,515 kg/ha이며 수수수단그라스 교잡종의 후작으로 재배된 총체 영양보리의 2년간 평균 수량은 8,515 kg/ha으로총체 영양보리의 수량은 수수 수단그라스 교잡종 이모작으로 재배한 경우가 총체 벼 후작에 비해 현저하게 높게 나타났다(p<0.05). 수수수단그라스 교잡종과 총체 영양보리 이모작에서 총체 영양보리의 조단백질함량, NDF,ADF 및 TDN 함량은 총체 벼 후작물로 재배된 총체 영양보리와 함량 차이가 나지 않았다.경작형태별 우분액비 시용에 따른 토양 내pH, 전질소, 유기물 함량은 시험 전에 비해 시험 종료 후에 현저하게 증가하는 경향을 나타냈다(p<0.05). 그러나 인산함량은 시험전후에차이는 나타나지 않았다. 경작형태별 우분액비시용에 따른 토양 내 칼슘, 나트륨, 마그네슘및 칼리 농도는 시험 전에 비해 시험 종료 후에 현저하게 증가하는 경향을 나타냈다(p<0.05).경작형태별 우분액비 시용에 따른 용탈수 중암모니아성 질소, 질산성 질소, 인산염인, 염소,칼슘, 칼리, 마그네슘, 나트륨의 농도는 경작형태에 따른 확실한 차이를 보여주지 않았다.

This study was carried out to investigate effective condition for producing somatic cell nuclear transfer (SCNT) embryos of Jeju native cattle. As donor cells for SCNT, ear skin cells from Jeju native cattle were used. In experiment 1, the effect of recipient oocyte sources on the development of Jeju native cattle SCNT embryos were examined. Fusion rate of recipient oocyte and donor cell was not different between the Hanwoo and Holstein recipient oocytes (86.0% vs 89.9%). The rate of embryos developing to the blastocyst stage was significantly (p<0.05) higher in Hanwoo recipient oocytes than in Holstein recipient ones (28.2% vs 14.7%). Blastocysts derived from Hanwoo recipient oocytes contained higher numbers of total cells than those derived from Holstein ones ( vs ), although there were no significant difference. The mean proportion of apoptotic cells in blastocyst was not different between the sources of recipient oocytes. In experiment 2, the development of Jeju native cattle and Hanwoo SCNT embryos were compared. Hanwoo oocytes were used as the recipient oocytes. Fusion rate was not different between the Jeju native cattle and Hanwoo SCNT embryos (92.1% vs 92.9%). The blastocyst rate of SCNT embryos was significantly (p<0.05) lower in Jeju native cattle than in Hanwoo (16.9% vs 31.0%). Blastocysts derived from Jeju native cattle SCNT embryos contained smaller numbers of total cells than those derived from Hanwoo ones ( vs ), but there were no significant difference. The mean proportion of apoptotic cells in blastocyst was not different between the Jeju native cattle and Hanwoo SCNT embryos. The present study demonstrated that Hanwoo recipient oocytes were more effective in supporting production of Jeju native cattle SCNT embryos, although Jeju native cattle SCNT embryos showed reduced developmental capacity when compared to Hanwoo SCNT embryos.

After spermatogenesis, spermatozoa come in contact with fluids in the epididymis where they mature. During ejaculation, spermatozoa are mixed with secretions from prostate gland, vesicular glands, and bulbourethral glands. During natural mating, seminal plasma is deposited in the female reproductive tract eliciting various physiological and immunological responses. With the advances in proteomics, the components of seminal plasma have been identified and the information may be valuable in identifying markers for fertility. Components of seminal plasma that affect fertility have been discovered and the mechanism of action of these factors has been determined. The objective of this study was to determine the specific seminal plasma proteins from Korean native cattle, Hanwoo, and Korean native brindle cattle (KNBC) with the long term goal of improving fertilization rate. After SDS-PAGE and 2-dimensional gel electrophoresis, proteins were identified by Q -ToF analysis. They include plasma serine protease inhibitor precursor and platelet-activating factor acetylhydrolase after SDS-PAGE. Number and density of the spots in 2-dimensional gels were higher in KNBC than Hanwoo. Proteins identified from the paired spots of both breeds include chain A, bull seminal plasma PDC-109 Fibronectin Type II module, BSP-30 kDa precursor, and Spermadhesin Z13 or its precursor. Interestingly, some proteins were identified from multiple spots. The functional differences of these diverse forms of the proteins may require further studies. With their previously reported roles in sperm capacitation by these proteins, the studies on the mechanism of action, ligand interaction and the variation in the genome may help improving fertility in cattle.

Since the Bovine sequencing and HapMap projects, there have been millions of genetic variations particularly including single nucleotide polymorphisms (SNPs) available throughout the cattle genome. While cataloguing substantial amounts of SNPs, copy number variation (CNV) has recently become getting great attention as an another form of genetic variation which is extensively distributed across the cattle genome. As it has been well known that CNVs can account for substantial proportions of phenotypic variance in other species including human, CNVs are highly expected to explain genetic variations of diverse economically important traits in cattle. Currently, two main approaches such as hybridization-based microarray and massively parallel sequencing-based method have been successfully applied to detect CNVs throughout the cattle genome. Although there is obvious difference of capabilities to detect genome-wide CNVs at fine scales between different platforms applied, all currently completed investigations exhibited that CNVs are extensively spread throughout the cattle genome as observed in other species. Despite these successes, there are still severe lacks of researches to identify multiple levels of CNVs from diverse cattle or multiple individuals, suggesting that there are a number of CNVs remained undiscovered. Furthermore, there are almost few investigations available to elucidate how each CNV is associated with traits of interest in cattle, so such functional study should be followed along with saturating most of potential CNVs on cattle genome.

The objective of this research was to investigate the effect of dietary cottonseed meal (CSM) supplementation on carcass and meat quality characteristics of Hanwoo (Korean cattle) bulls. Twenty two months-old-Hanwoo bulls of eight heads (4 heads per treatments) were fed for 5 months on a diet with or without (control) CSM (500 g/head/day). The samples of M. longissimus dorsi from carcasses were used for the quality measurement. Dietary CSM supplementation did not affect the carcass traits of bulls and pH value, drip loss, water-holding capacity and fatty acid composition of beef loin. Crude protein and crude ash content of beef loin were significantly (p<0.05) higher in beef loin from bulls fed CSM than in the control. During storage of 5 days at 4℃, CIE a*, b*, C* and total color values were significantly (p<0.05) higher in beef loin from bulls fed CSM than in the control. Overall, the present results indicate that dietary CSM supplementation may improve the oxidation stability of Hanwoo beef loin.

This study was conducted to estimate heritabilities and genetic and phenotypic correlations among growth traits (weaning weight, weight of 12 month, weight of 18 month, weight of 24 month). Growth data collected from steers (n=3,321) and 8,818 animals in pedigree were used for estimation of genetic parameters. Traits evaluated included live weight at 4 month (W4), 12 month (W12), 18 month (W18) and 24 month (W24). Parameters were estimated using an multitrait animal model and derivative-free restricted maximum likelihood procedures. Heritabilities estimated for growth traits at W4, W12, W18 and W24 were 0.21, 0.11, 0.08 and 0.14, respectively. Genetic correlations were in the range of 0.79 to 0.87. Phenotypic correlations were in the range of 0.16 to 0.81.