• Journal of Microbiology and Biotechnology
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• v.25 no.10
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• pp.1606-1613
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• 2015

Porcine pleuropneumonia is an infectious disease caused by Actinobacillus pleuropneumoniae. The identification of A. pleuropneumoniae genes, specially expressed in vivo, is a useful tool to reveal the mechanism of infection. IVIAT was used in this work to identify antigens expressed in vivo during A. pleuropneumoniae infection, using sera from individuals with chronic porcine pleuropneumonia. Sequencing of DNA inserts from positive clones showed 11 open reading frames with high homology to A. pleuropneumoniae genes. Based on sequence analysis, proteins encoded by these genes were involved in metabolism, replication, transcription regulation, and signal transduction. Moreover, three function-unknown proteins were also indentified in this work. Expression analysis using quantitative real-time PCR showed that most of the genes tested were up-regulated in vivo relative to their expression levels in vitro. IVI (in vivo-induced) genes that were amplified by PCR in different A. pleuropneumoniae strains showed that these genes could be detected in almost all of the strains. It is demonstrated that the identified IVI antigen may have important roles in the infection of A. pleuropneumoniae.

• Journal of Microbiology and Biotechnology
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• v.28 no.12
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• pp.2095-2105
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• 2018

In our previous studies, we have identified several in vivo-induced antigens and evaluated their potential as subunit vaccine candidates in a murine model, in which the recombinant protein GalT showed the most potent immunogenicity and immunoprotective efficacy against Actinobacillus pleuropneumoniae. To exploit a more efficient way of delivering GalT proteins, in this study, we employed the widely studied E. coli outer membrane vesicles (OMVs) as a platform to deliver GalT protein and performed the vaccine trial using the recombinant GalT-OMVs in the murine model. Results revealed that GalT-OMVs could elicit a highly-specific, IgG antibody titer that was comparable with the adjuvant GalT group. Significantly higher lymphocyte proliferation and cytokines secretion levels were observed in the GalT-OMVs group. 87.5% and 50% of mice were protected from a lethal dose challenge using A. pleuropneumoniae in active or passive immunization, respectively. Histopathologic and immunohistochemical analyses showed remarkably reduced pathological changes and infiltration of neutrophils in the lungs of mice immunized with GalT-OMVs after the challenge. Taken together, these findings confirm that OMVs can be used as a platform to deliver GalT protein and enhance its immunogenicity to induce both humoral and cellular immune responses in mice.

• Korean Journal of Veterinary Service
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• v.35 no.2
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• pp.139-145
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• 2012

Prevalence of major legal communicable diseases in bovine and swine had been monitored in Jeonbuk province from year 2004 to 2008. At least 1 communicable disease had been reported in 687 heads from 68 bovine farms and 17 farms (25.0%) of the 68 positive farms had 1~2 additional outbreaks during the surveillance. By disease, enzootic bovine leukosis, Johne's disease and Akabane disease were occurred in 53 farms (582 heads), 14 farms (100 heads) and 1 farm (5 heads), respectively. Swine communicable diseases were occurred in 4,466 heads from 63 swine farms and 18 farms (28.6%) of the 63 positive farms had 1~2 additional outbreaks during the surveillance. By disease, Aujeszky's disease (AD), porcine epidemic diarrhea (PED), classical swine fever (CSF), porcine reproductive and respiratory syndrome (PRRS), porcine transmissible gastroenteritis (TGE), atrophic rhinitis (AR) and Japanese encephalitis in swine (JE) were occurred in 20 farms (70 heads), 20 farms (2,817 heads), 12 farms (258 heads), 6 farms (1,257 heads), 1 farm (50 heads), 1 farm (2 heads) and 1 farm (10 heads), respectively. In total, 10 communicable diseases (1 species of first-class, 3 species of second-class, and 6 species of third-class) were reported. The first-class diseases were CSF. Johne's disease, and Aujeszky's disease. JE was the second-class and Akabane disease, enzootic bovine leukosis (EBL), PED, PRRS, TGE and AR were third-class diseases.

• Journal of Veterinary Science
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• v.22 no.1
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• pp.13.1-13.14
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• 2021

African swine fever (ASF) is one of the most complex infectious swine diseases and the greatest concern to the pig industry owing to its high mortality and no effective vaccines available to prevent the disease. Since the first outbreak of ASF in pig farms, ASF has been identified in 14 pig farms in four cities/counties in South Korea. The outbreak was resolved in a short period because of the immediate control measures and cooperative efforts. This paper reviews the ASF outbreak and the experience of successfully stopping ASF in pig farms in South Korea through active responses to prevent the spread of ASF. In addition, suitable changes to build a sustainable pig production system and collaborative efforts to overcome the dangerous animal disease, such as ASF, are discussed.

• Journal of Veterinary Clinics
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• v.28 no.4
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• pp.415-421
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• 2011

Currently, various diseases reside in Korean swine farms and affect production performance of the farms greatly. These damages from disease are further aggravated by the concurrent infection of other disease. In this study, y investigating the distribution of porcine reproductive and respiratory syndrome virus (PRRSV), porcine circovirus type 2 (PCV2), Salmonella spp. in farms, correlation between the damage and the prevalence of disease was analyzed. Ten selected Korean swine farms that uses PCV2 vaccine were tested for presence of antibody and antigen of PRRSV, PCV2, Salmonella spp. per ages of pigs, 4weeks, 7weeks, 11weeks and 17weeks, respectively. The results were analyzed by dividing the farms in to groups with MSY above 19, and that with MSY below 19. Then calculating the distribution of disease each ages of pigs. Farms with MSY below 19 showed high prevalence of disease by PRRSV, PCV2 and Salmonella spp.. In this group, the detection rate of PCV2 and Salmonella spp. was increased by the activation/viremia of PRRSV in the young ages of pigs. The results are proved that the correlation between disease prevalence and production performance in Korean swine farms were very significant. The prevalence of PRRSV is more important index which influence to the productivity in current prevalence of diseases.

• Journal of Veterinary Science
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• v.23 no.5
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• pp.32.1-32.11
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• 2022

Background: Classical swine fever (CSF) is a severe infectious disease of pigs that causes significant economic losses to the swine industry. Objectives: This study developed a solid-phase blocking enzyme-linked immunosorbent assay (spbELISA) method for the specific detection of antibodies against the CSF virus (CSFV) in porcine serum samples. Methods: A spbELISA method was developed based on the recombinant E2 expressed in Escherichia coli. The specificity of this established spbELISA method was evaluated using reference serum samples positive for antibodies against other common infectious diseases. The stability and sensitivity were evaluated using an accelerated thermostability test. Results: The spbELISA successfully detected the antibody levels in swine vaccinated with the C-strain of CSFV. In addition, the detection ability of spbELISA for CSFV antibodies was compared with that of other commercial ELISA kits and validated using an indirect immunofluorescence assay. The results suggested that the spbELISA provides an alternative, stable, and rapid serological detection method suitable for the large-scale screening of CSFV serum antibodies. Conclusions: The spbELISA has practical applications in assessing the vaccination status of large pig herds.

• The Korea Swine Journal
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• v.21 no.2 s.234
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• pp.102-104
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• 1999

• Korean Journal of Veterinary Research
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• v.57 no.1
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• pp.31-36
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• 2017

Japanese encephalitis (JE) is an important zoonosis caused by the mosquito-transmitted JE virus (JEV), which is a causative agent of reproductive failure in pregnant sows. Detection of JEV antibodies in swine is performed by hemagglutination inhibition (HI), virus neutralization (VN), and the plaque reduction neutralization test (PRNT). The most stringent PRNT is the 90% endpoint PRNT ($PRNT_{90}$). These conventional assays are difficult to carry out in diagnostic laboratories with insufficient instruments or cell culture systems. An alternative assay that is easily conducted and time efficient is required. In this study, we improved the indirect enzyme-linked immunosorbent assay (I-ELISA) with clarified antigen for the detection of JEV antibodies. The I-ELISA results obtained from 175 swine serum samples were compared with HI, VN, and $PRNT_{90}$ results. The sensitivity of I-ELISA was 91.8%, 95.0%, and 94.7% compared with HI, VN, and $PRNT_{90}$ results, respectively. The specificity of I-ELISA was 92.2%, 94.7%, and 94.7% compared with HI, VN, and $PRNT_{90}$ results, respectively. Moreover, the I-ELISA results were significantly correlated with the HI (r = 0.93), VN (r = 0.95), and $PRNT_{90}$ (r = 0.92) results. These results suggest that the improved I-ELISA is useful for serosurveillance of JEV in swine.

• Journal of the korean veterinary medical association
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• v.16 no.3
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• pp.129-136
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• 1980

Present experiments were conducted to classify the epizootic skin diseases of swine and determine the etiological agent of swine parakeratosis in Korea. Twnty-three herds of swine with skin disease in Gyongbug prefecture were examined clinicopathologicall

• The Korea Swine Journal
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• v.15 no.9 s.169
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• pp.140-146
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• 1993