• Journal of Embryo Transfer
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• v.21 no.1
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• pp.45-51
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• 2006

This study was carried out to investigate effect of claw trimming on milk yield and its composition in Holstein at different lactation stages. 1 . There was no difference in daily milk yield between control and claw trimming in early, mid and late lactating Holsteins. 2. Somatic cell count (SCC) was lower in early lactation and it was higher in late lactation when claws were trimmed in Holstein. However, claw trimming did not affect SCC during mid lactation in Holstein. 3. Milk fat, protein and total solids were decreased during late lactation in Holstein after claw trimming. However, milk composition was not affected by claw trimming in early and mid lactating Holsteins.

• Journal of Korean Society of Forest Science
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• v.101 no.4
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• pp.613-618
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• 2012

The 5-year-old seedlings and emblings which regenerated from somatic embryos were compared to the height, DBH, foliar characteristics, content of chlorophyll (chlorophyll a, b and total chlorophyll), carotenoid and leaf microstructure in Liriodendron tulipifera. In comparison of height and DBH (diameter at breast height), no significant differences were found in height (seedling, 3.8 m; embling, 3.87 m) and DBH (seedling, 12.09 cm; embling, 12.53 cm). The emblings and seedlings were similar in values of length (seedling, 108.11 mm, embling, 113.59 mm), width (seedling, 149.1 mm; embling, 167.71 mm), surface area (seedling, $119.92mm^2$; embling, $164.43mm^2$), fresh weight (seedling, 2.1 g; embling, 2.62 g) of leaf, and length (seedling, 81.49 mm; embling, 98.41 mm) and thickness (seedling, 1.66 mm; embling, 1.98 mm) of petiole. In case of chlorophyll content in the leaves, the chlorophyll a (seedlings, $11.2{\mu}g/g$; emblings, $13.2{\mu}g/g$), b (seedlings, $4.8{\mu}g/g$; emblings, $5.4{\mu}g/g$) and total content were higher in emblings ($930.2{\mu}g/g$) than seedlings ($800.1{\mu}g/g$), however, content of carotenoid (seedlings, $260.3{\mu}g/g$; embling, $265.2{\mu}g/g$) showed similar in both plants. Leaves of emblings had a similar pattern of histological structure (palisade or sponge parenchyma) to that of seedlings leaves. Therefore, the results showed that there were no remarkable growth differences when compared with 5-year-emblings and seedlings of yellow poplar.

• Korean Journal of Medicinal Crop Science
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• v.4 no.1
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• pp.78-85
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• 1996

The effects of growth regulators, sucrose and gelling agents were investigated to increase the efficiency of the callus growth and plant regenerarion in tissue culture of Angelica koreana Max. The fresh weight and dry weight of subcultured callus was highest in MS medium supplemented with 1 mg/l 2,4-D. Callus growth was excellent in 2% sucrose, but it was inhibited in propotion to sucrose content. Effect of gelling agents on callus growth was highest on 1.2% agar and 0.4% Gelrite medium, respectively. The browning of callus was protected on the media supplemented with 10 mg/l ABA and 5 or 10 mg/l $AgNO_3$. In the callus induction and growth from the peduncle of immature inflorescence, 2,4-D was more effective than NAA, and the frequency of callus induction was highest as 81.7% in 2 mg/l 2,4-D. Plant was not regenerated from the callus derived from young leaf. Somatic embryos were developed from the surface of callus drived from the peduncle of immature inflorescence in the medium containing 0.5 mg/l 2,4-D, 1 mg/l kinetin, 5 mg/l ABA and 5 mg/l $AgNO_3$. Plants were developed from the matured somatic embryos in the medium supplemented with 0.2 mg/l 2,4-D and 1 mg/l kinetin.

• Reproductive and Developmental Biology
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• v.31 no.2
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• pp.83-90
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• 2007

Insulin-like growth factor II (IGF2) and H19 genes are mutually imprinted genes which may be responsible for abnormalities in the cloned fetuses and offspring. This study was performed to identify putative differentially methylated regions (DMRs) of porcine H19 locus and to explore its genomic imprinting in in vitro fertilized (IVF) and somatic cell nuclear transferred (SCNT) embryos. Based on mice genomic data, we identified DMRs on H19 and found porcine H19 DMRs that included three CTCF binding sites. Methylation patterns in IVF and SCNT embryos at the 2-, 4-, $8{\sim}16$-cells and blastocyst stages were analyzed by BS (Bisulfite Sequencing)-PCR. The CpGs in CTCF1 was significantly unmethylated in the 2-cell stage IVF embryos. However, the 4- (29.1%) and $8{\sim}16$-cell (68.2%) and blastocyst (48.2%) stages showed higher methylation levels (p<0.01). On the other hand, SCNT embryos were unmethylayted ($0{\sim}2%$) at all stages of development. The CpGs in CTCF2 showed almost unmethylation levels at the 2-,4- and $8{\sim}16$-cell and blastocyst stages of development in both IVF ($0{\sim}14.1%$) and SCNT ($0{\sim}6.4%$) embryos. At all stages of development, CTCF3 was unmethylated in IVF ($0{\sim}17.3%$) and SCNT ($0{\sim}1.2%$) embryos except at the blastocyst stage (54.5%) of IVF embryos. In conclusion, porcine SCNT embryos showed an aberrant methylation pattern comprised to IVF embryos. Therefore, we suggest that the aberrant methylation pattern of H19 loci may be a reason for increased abnormal fetus after embryo transfer of porcine SCNT embryos.

• Journal of Animal Science and Technology
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• v.62 no.4
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• pp.565-576
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• 2020

Recently, Jersey cattle was introduced and produced by embryo transfer to Korea. This study was conducted to investigate the differences of milk compositions between Jersey and Holstein cows and the relationship between days in milk (DIM) and milk compositions during early lactation. Data were collected from twelve lactating cows from Department of Animal Resources Development at National Institute of Animal Science. Cows in parity 1 were used, and calved at spring from April to March of 2017. All cows were housed in two sections within a free-stall barn, which divided into six from each breed, and received a basal total mixed ration. Milk samples of each cow were collected at 3 DIM and 30 DIM for analyzing the milk compositions, including fatty acids (FA), amino acids and minerals. Total solids, citrate, and milk urea nitrogen level were differed between the breeds (p < 0.05). As DIM went from 3 to 30, milk protein, total solids, and somatic cell count decreased (p < 0.05), but lactose increased in all breed milk (p < 0.05). Citrate and free fatty acid (FFA) elevated in Jersey milk (p < 0.05), whereas reduced in Holstein milk (p < 0.05). Proportions of some individual FA varied from the breeds. Myristic (C14:0), palmitic (C16:0), and arachidonic acid (C20:4) in milk from all cows were higher at 3 DIM than at 30 DIM (p < 0.05). Also, stearic (C18:0) and oleic acid (C18:1) were lower at 3 DIM than at 30 DIM (p < 0.05), and the C18:1 to C18:0 ratio was significantly differed in DIM × breed interactions (p < 0.05). The contents of the individual amino acids did not differ from the breeds. Calcium, phosphorous, magnesium, and zinc (Zn) contents was significantly increased in Holstein milk than Jersey milk at 3 DIM. Also, K and Zn concentrations were higher in Holstein milk than in Jersey milk at 30 DIM (p < 0.05). It was concluded that Jersey cows would produce more effective milk in processing dairy products and more proper energy status compared with Holstein cows in early lactation under the same environmental and nutritional conditions.

• Reproductive and Developmental Biology
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• v.32 no.1
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• pp.33-38
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• 2008

DNA methylation is involved in tissue-specific gene control and essential for normal embryo development Octamer-binding transcription factor 4 (Oct-4) is one of the most important transcription factors for early differentiation. This study was performed whether the bovine Oct-4 is tissue specific or developmental dependent epigenetic mark, we investigated transcripts and the methylation status of CpGs of 5'-promoter region of Oct-4 in bovine preimplantation embryos. Oct-4 transcripts were highly detected in morula and blastocyst, while they were present low levels in sperm and 2- to 8-cell stage embryos. These results suggest that de novo expression of Oct-4 initiates at morula stage of embryogenesis. Here we determined that there is a tissue-dependent differentially methylated region (T-DMR) in the 5'-promoter region of Oct-4. The methylation status of the Oct-4 T-DMR was distinctively different in the oocyte from that in the sperm and adult somatic tissues and changed from zygote to blastocyst stage, suggesting that active methylation and demethylation occur during preimplantation development. Based on these results, the 5'-promoter region of Oct-4 gene is target for DNA methylation and the methylation status changes variously during embryonic development in bovine.

• Korean Journal of Animal Reproduction
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• v.24 no.3
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• pp.289-297
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• 2000

This study was conducted to investigate whether various protein sources and co-culture affect in vitro development of porcine zygotes derived from In vitro maturation/fertilization (IVM/IVF). These results obtained in these experiments are summarized as follows 1. When porcine oocytes matured and fertilized In vitro were cultured in NCSU 23 medium supplemented with various BSA concentrations (0.4, 0.8 and 3.2%), In vitro developmental rates of porcine zygotes to blastocyst stage were 22.9, 18.4 and 14.6%, respectively. High concentration of BSA (3.2%) showed a smaller nuclei number (36.1$\pm$11.8) of blastocysts than 0.4 and 0.8% BSA groups (53.2$\pm$27.4 and 61.2$\pm$22.5, respectively) (P<0.05). This result indicates that high concentration of BSA is detrimental on preimplantation development of IVF-derived porcine embryos. 2. No differences were detected in the developmental rate and mean nuclei number of porcine embryos between 10 and 20% FBS concentrations in culture medium. 3. IVF-derived porcine embryos co-cultured with mouse or porcine embryonic fibroblast cells showed a lower development to the blastocyst stage than those without co-culture system. Consequently, the present study suggests that high concentration of BSA as a protein source in culture medium suppresses development potential of porcine embryos produced In vitro. In addition, co-culture with somatic cells is not effective on in vitro development of IVF-derived porcine embryos to blastocyst stage.

• Plant Resources
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• v.5 no.1
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• pp.29-44
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• 2002

In this study, plant regeneration through in vitro culture from plantlet stems of Yooja (C. junos Sieb.) and trifoliate orange (P. trifoliata Rafin.) was attempted to make mass-production system of virus-free plants having the same genotype with mother plant. In order to investigate physiological change depending on the developmental stage of plant regeneration, the changes of total protein, peroxidase and esterase activity and their isozyme patterns as well were examined in 1/2 MS medium. The results are as follows : 1. The MS medium for the optimal callus induction and shoot formation was utilized. The medium was supplemented either with 2,4-D and Kinetin or with BA and NAA. The optimal concentrations were the combination of 1.0mg/ 2,4-D +0.3mg/ Kinetin and 1.0mg BA +0.3mg NAA in callus induction and shoot formation, respectively. 2. For the plant regeneration from somatic embryos, 1/2 MS medium was used with supplements of growth regulators (free, 1.0mg/ IBA +1.0mg/ BA ,0.5mg/ IBA +0.5mg/ BA). Shooting and rooting were the best in the treatment of 0.5mg/ IBA and 0.5mg/ BA combination. 3. The total protein content has a tendency of increase with the developmental stage of embryo, but it was decreased at the plantlet. Also it was the highest at 8 and 6 weeks stage in C. junos Sieb. and P. trioliata Rafin, respectively. In the SDS-PAGE pattern of protein, C. junos Sieb. showed bands of 29.0 and 40kDa at 10 weeks. The 45,66 and 97.4 kDa bands at 10 weeks of culture were shown in P. trifoliata Rafin. 4. The highest esterase activity was shown at the 6 and 8 weeks of culture in C.junos Sieb. and P. trifoliata Rafin.., respectively. 5. Esterase isozyme patterns were shown difference according to the developmental stage. In C. junos Sieb. a new band was observed at pl 7.7 following 4 weeks culture. On the other hand, new bands in P. trifoliata Rafin. were observed at pl 7.5~6.5 following 4 and 6 weeks culture, respectively.

• Korean Journal of Plant Resources
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• v.18 no.1
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• pp.15-21
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• 2005

Korean ginseng(Panax ginseng C.A. Meyer) is very difficult to obtain stable production of qualified ginseng roots because of variable stresses in soil environments. In transformation of ginseng with betain aldehyde dehydrogenase gene, compounds synthesized for controlling osmotic pressure such as proline, glycine, betaine, polyols and sugar were accumulated in cell for salt resistance in transgenic plants. 2 Agrobactgerium conjugants were acquired with bet A and bet B genes for solt resistant plants. A. tumefaciens MP90/pBetA and A. tumefaciens MP90/pBetB were recombined for increasing the tolerance to salt stress. To confirm the transformation of the binary vector, tobacco plant was transformed, and the transformant can grow on media containing high concentration of kanamycin. To identify NPT 11, BetA and BetB genes of the transformants, the band on the agarose was confirmed by PCR and RT-PCR techniques. The transformants of ginseng with bet A and bet B genes were acquired on the phytohormone free basic MS media containing only antibiotics and 1M mannitol used for selection of transgenic plant, but the transfomation efficiency for BetA and BetB was very low.

• Korean Journal of Animal Reproduction
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• v.20 no.3
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• pp.323-331
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• 1996

Predetermination of sex in mammalian species has many aspects of application including the prenatal diagnoses of genetic disorders in humans and sex-selected breeding programs in the animal industry. Embryos sexing can be carried out using the polymerase chain reaction (PCR) to amplify specific sequences present in the sex chromosomes, or by fluorescent in situ hybridization (FISH) of specific probes to the X and Y chromosomes. A 3.3 kb porcine male-specific DNA fragment (pEM39) was cloned previously in our laboratory. In this study, FISH and PCR methods were employed to examine if the pEM39 can be used a sex-specific DNA probes Porcine ovaries were obtained from a local slaughter house and oocytes collected. All oocytes were subjected to in vitro maturation followed by 1n vitro fertilization. Parthenogenetically activated embryos were served as a negative control. Embryonic samples were collected at the 2-cell stages and PCR was performed to analyze DNA. Among 10 embryos examined, four embryos were identified as males and six were females. The cloned male-specific DNA fragment showed male-specificity for the cells in the liver tissue and the porcine early embryos by FISH. It was also demonstrated that the cloned male-specific DNA is localized on the hetero chromatic region of the long arm in the Y chrom-osome (Yq) as shown by the FISH and karyotyping. The results suggest that the cloned male-specific DNA fragment may be useful for predetermination of sex with a few embryonic cells. The porcine male-specific sequence can be a reliable index for embryo sexing by PCR.