• Asian-Australasian Journal of Animal Sciences
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• v.4 no.4
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• pp.305-328
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• 1991

Pig breeding programs have been very successful in the improvement of animals by the simple expedient of focusing on a few traits of economic importance, particularly growth efficiency and leanness. Further reductions in leanness may become more difficult to achieve, due to reduced genetic variation, and less desirable, due to adverse correlated effects on meat and eating quality. Best linear unbiased prediction (BLUP) of breeding values makes possible the incorporation of data from many sources and increases the value of including traits such as sow performance in the breeding objective. Advances in technology, such as electronic animal identification, electronic feeders, improved ultrasonic scanners and automated data capture at slaughter houses, increase the number of sources of information that can be included in breeding value predictions. Breeding program structures will evolve to reflect these changes and a common structure is likely to be several or many breeding farms genetically linked by A.i., with data collected on a number of traits from many sources and integrated into a single breeding value prediction using BLUP. Future developments will include the production of a porcine gene map which may make it possible to identify genes controlling economically valuable traits, such as those for litter size in the Meishan, and introgress them into nucleus populations. Genes identified from the gene map or from other sources will provide insight into the genetic basis of performance and may provide the raw material from which transgenic programs will channel additional genetic variance into nucleus populations undergoing selection.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.3
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• pp.358-363
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• 2008

The intracytoplasmic sperm injection (ICSI) procedure has recently been utilized to produce transgenic animals and may serve as an alternative to the conventional pronuclear microinjection in species such as pigs whose ooplasm is opaque and pronuclei are often invisible. In this study, the effects of sperm membrane disruption and electrical activation of oocytes on in vitro development and expression of transgene green fluorescent protein (GFP) in ICSI embryos were tested to refine this recently developed procedure. Prior to ICSI, sperm heads were treated with Triton X-100+NaCl or Triton X-100+NaCl+NaOH, to disrupt membrane to be permeable to exogenous DNA, and incubated with linearized pEGFP-N1 vector. To induce activation of oocytes, a single DC pulse of 1.3 kV/cm was applied to oocytes for $30{\mu}sec$. After ICSI was performed with the aid of a micromanipulator, in vitro development of embryos and GFP expression were monitored. The chemical treatment to disrupt sperm membrane did not affect the developmental competence of embryos. 40 to 60% of oocytes were cleaved after injection of sperm heads with disrupted membrane, whereas 48.6% (34/70) were cleaved without chemical treatment. Regardless of electrical stimulation to induce activation, oocytes were cleaved after ICSI, reflecting that, despite sperm membrane disruption, the perinuclear soluble sperm factor known to mediate oocyte activation remained intact. After development to the 4-cell stage, 11.8 (2/17, Triton X-100+NaCl+NaOH) to 58.8% (10/17, Triton X-100+NaCl) of embryos expressed GFP. The expression of GFP beyond the stage of embryonic genome activation (4-cell stage in the pig) indicates that the exogenous DNA might have been integrated into the porcine genome. When sperm heads were co-incubated with exogenous DNA following the treatment of Triton X-100+NaCl, GFP expression was observed in high percentage (58.8%) of embryos, suggesting that transgenic pigs may efficiently be produced using ICSI.

• Journal of Veterinary Clinics
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• v.27 no.4
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• pp.330-335
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• 2010

This study was performed to compare the anesthetic and cardiorespiratory effects of the tiletamine/zolazepam/xylazine (TZX) combination and tiletamine/zolazepam/midazolam (TZM) combination. Eight healthy Landrace $\times$ Yorkshire pigs were randomly assigned to two groups. Each group was composed of four pigs. The pigs in group 1 (TZX) received tiletamine/zolazepam (2 mg/kg, IM) and xylazine (2 mg/kg, IM). The pigs in group 2 (TZM) received tiletamine/zolazepam (2 mg/kg, IM) and midazolam (0.5 mg/kg, IV). Induction time, anesthesia time and standing time were recorded for each pig. The scores of anesthetic effects were subjectively evaluated every 15 minutes during anesthesia. Cardiopulmonary parameters (heart rate, arterial blood pressure, respiratory rate and rectal temperature) were monitored and recorded 0, 5, 15, 30, 45 and 60 minutes after administration of drugs. Arterial blood gases ($pH_a$, $P_aCO_2$ and $P_aO_2$) and oxygen saturation ($SO_2$) were analyzed at same times. The scores of anesthetic effects decreased in the TZX group compare with the TZM group. From 5 to 85 minutes the mean heart rate in the TZX group was significantly lower than those in the TZM group. Mean arterial blood pressure in the TZX group was significantly higher than those in the TZM group at 5, 15 and 30 minutes. Both drug combinations provided a smooth induction and good immobilization. Scores of anesthetic effects in the TZM group were better than those in the TZX group. The effects to the cardiorespiratory function and temperature were lesser in the TZM group than those in the TZX group. In conclusion, when the two drug combinations were compared, the TZM group showed better anesthetic effects and less cardiorespiratory effects.

• Journal of Veterinary Clinics
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• v.27 no.6
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• pp.647-651
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• 2010

The advantages of the $CO_2$ laser are offset by the delay in laser wound healing secondary to thermal damage. To minimize the undesirable thermal damage of the $CO_2$ laser, investigators have developed technical advances in the delivery system of the laser energy. This study compared tissue healing of the continuous and the pulsed modes $CO_2$ laser wounds in an animal surgery model. Five healthy Landrace and Yorkshire mixed breeds of both genders were used (45-51 kg, 4-6 months old, three males and two females). A full thickness wound of skin ($2{\times}2{\times}2cm^2$) was made over on the each pig's both sides of dorsal midline at 0, 7, 14, and 18 days. The wounds created at 18, 14, 7 and 0 days were named post-wounding day (PWD) 3, 7, 14 and 21, respectively. In each pig, one wound (left side) was treated pulsed $CO_2$ laser and the other wound (right side) was treated continuous wave $CO_2$ laser. Each wound was closed with two interrupted suture of 3-0 sutures. At 21 days after initial wounding, each wound was taken for histological evaluations. The degrees of reepithelialization were performed more prominently in the pulsed mode group than in the continuous mode group. The degrees of granulation were greater significantly in pulsed mode group than those in the continuous mode on PWD 3 (p < 0.05). The degrees of fibroblasts in the pulsed mode group were greater significantly in comparison to those in the continuous mode group on PWD 7, (p < 0.05). In conclusion, reepithelialization, granulation and fibroblasts in the pulsed mode group were greater markedly in comparison to those in the continuous mode group. It was considered that pulsed mode $CO_2$ laser was more suitable for the skin incision than the continuous mode $CO_2$ laser.

• Reproductive and Developmental Biology
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• v.35 no.1
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• pp.23-31
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• 2011

Two piglets and one juvenile pig were used to investigate closely what types of cells express green fluorescent protein (GFP) and if any, whether the GFP-tagged cells could be used for stem cell transplantation research as a middle-sized animal model in bone marrow cells of recloned GFP pigs. Bone marrow cells were recovered from the tibia, and further analyzed with various cell lineage markers to determine which cell lineage is concurrently expressing visible GFP in each individual animal. In the three animals, visible GFP were observed only in proportions of the plated cells immediately after collection, showing 41, 2 and 91% of bone marrow cells in clones #1, 2 and 3, respectively. The intensity of the visible GFP expression was variable even in an individual clone depending on cell sizes and types. The overall intensities of GFP expression were also different among the individual clones from very weak, weak to strong. Upon culture for 14 days in vitro (14DIV), some cell types showed intensive GFP expression throughout the cells; in particular, in cytoskeletons and the nucleus, on the other hand. Others are shown to be diffused GFP expression patterns only in the cytoplasm. Finally, characterization of stem cell lineage markers was carried out only in the clone #3 who showed intensive GFP expression. SSEA-1, SSEA-3, CD34, nestin and GFAP were expressed in proportions of the GFP expressing cells, but not all of them, suggesting that GFP expression occur in various cell lineages. These results indicate that targeted insertion of GFP gene should be pursued as in mouse approach to be useful for stem cell research. Furthermore, cell- or tissue-specific promoter should also be used if GFP pig is going to be meaningful for a model for stem cell transplantation.

• Development and Reproduction
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• v.19 no.2
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• pp.79-84
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• 2015

The Korean native pig (KNP) have been considered as animal models for animal biotechnology research because of their relatively small body size and their presumably highly inbred status due to the closed breeding program. However, little is reported about the use of KNP for animal biotechnology researches. This study was performed to establish the somatic cell nuclear transfer (SCNT) protocol for the production of swine leukocyte antigens (SLA) homotype-defined SCNT KNP. The ear fibroblast cells originated from KNP were cultured and used as donor cell. After thawing, the donor cells were cultured for 1 hour with 15 ${\mu}M$ roscovitine prior to the nuclear transfer. The numbers of reconstructed and parthenogenetic embryos transferred were $98{\pm}35.2$ and $145{\pm}11.2$, respectively. The pregnancy and delivery rate were 3/5 (60%) and 2/5 (40%). One healthy SLA homotype-defined SCNT KNP was successfully generated. The recipient-based individual cloning efficiency ranged from 0.65 to 1.08%. Taken together, it can be postulated that the methodological establishment of the production of SLA homotype-defined cloned KNP can be applied to the generation of transgenic cloned KNP as model animals for human disease and xenotransplantation researches.

• Korean Journal of Veterinary Service
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• v.32 no.1
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• pp.27-32
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• 2009

We studied the seroprevalence of four respiratory pathogens in Korean swine farms located in Chungnam, Chungbuk, Gyeongnam and Gyeongbuk provinces during the period of spring of 2007 to winter of 2008. Serological tests were performed using commercial ELISA kits. A total of 530 serum samples were tested for the antibodies against porcine reproductive and respiratory syndrome virus (PRRSV), porcine circovirus type 2 (PCV2), Mycoplasma hyopneumoniae (M. hyo) and Actinobacillus pleuropneumoniae (APP). Seroprevalence for four respiratory pathogens were estimated by ELISA-positive rates of the submitted samples. The overall seropositive rates of PRRSV, APP, M. hyo and PCV2 were 32.6%, 10.6%, 38.4% and 88.5%, respectively. By production stage, the seropositive rate for PRRSV was highest in nursery pig populations (46.2%). In contrast, the highest seropositive rates of APP and M. hyo were observed in sow and growing pigs. However, the seroprevalence of PCV2 was ranged from 85.7% to 89.6%, showing no significant difference among the production stages. In the seroprevalence by season, PRRSV, APP and M. hyo infections revealed typical seasonal patterns that the peaks of the seropositive rates were observed between early winter and late spring. In case of PCV2, no particular seasonal patterns were noticed. The pig herds in Gyeongbuk province where PMWS was endemic during the period of survey showed the highest seropositive rates for PRRSV (44.6%), M. hyo (47.5%), and PCV2 (92.7%). Seropositive rates for APP of four provinces were approximately 10%. These results might be valuable for control and prevention of the respiratory diseases and helpful to define strategies related to vaccine applications.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2002.06a
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• pp.19-25
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• 2002

Researches on manipulation pluripotent stem cells derived from blastocysts or promordial germ cells (PGCs) have a great advantages for developing innovative technologies in various fields of life science including medicine, pharmaceutics, and biotechnology. Since the first isolation in the mouse embryos, stem cells or stem cell-like colonies have been continuously established in the mouse of different strains, cattle, pig, rabbit, and human. In the animal species, stem cell biology is important for developing transgenic technology including disease model animal and bioreactor production. ES cell can be isolated from the inner cell mass of blastocysts by either mechanical operation or immunosurgery. So, mass production of blastocyst is a prerequisite factor for successful undertaking ES cell manipulation. In the case of animal ES cell research, various protocol of gamete biotechnology can be applied for improving the efficiency of stem cell research. Somatic cell nuclear transfer technique can be applied to researches on animal ES cells, since it is powerful tool for producing clone embryos containing genes of interest. In this presentation, a brief review was made for explaining how somatic cell nuclear transfer technology could contribute to improving stem cell manipulation technology.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.6
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• pp.966-975
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• 1999

Technologies on preimplantation porcine embryos have been developed quickly and significantly. Successful development of systems for culture of porcine zygotes to the blastocyst stage has made it possible to utilize follicular oocytes for in vitro production of embryos and thus stimulated research on various embryo technologies. Recent technological development of embryo cryopreservation, separation of X- and Y-bearing spermatozoa and non-surgical embryo transfer has also made it easy to utilize in vivo- and in vitro-produced embryos for artificial manipulation to produce clones and transgenic pigs. Further progress in overcoming various problems associated with each embryo technology will result in acceptable efficiency to utilize porcine embryos with a high or increased quality. Combining these technologies will accelerate further expansion of the swine industry not only for meat production but also for the production of therapeutic recombinant proteins and xonografts.

• Journal of Applied Biological Chemistry
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• v.49 no.3
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• pp.86-89
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• 2006

The novel tetranuclear nickel (II) complex is a high rate accelerator in promoting hydrolysis of phosphate diesters. Nickel-bound bis-nitrophenyl phosphate (BNPP) can be $10^4$ times more reactive than the unbound BNPP. The large rate of enhancements by the complex slightly under basic condition has shown high catalytic activity in phosphate diester cleavage. The bell-shaped pH-rate profile indicated that the nickel-oxide form of the tetranuclear complex or its kinetic equivalent was the active species for cleaving BNPP. The catalytic hydrolysis between tetranuclear nickel (II) complex and phosphate diester proceeds via the formation of bidentate coordination of the anionic phosphate to the Ni (II) atom. This reveals that the complex has the possibility as artificial nuclease.