• Korean Journal of Veterinary Research
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• v.55 no.1
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• pp.9-12
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• 2015

Brachyspira (B.) hyodysenteriae is a causative agent of swine dysentery that is responsible for death and economic losses in the pig industry. It is imperative that clinical samples be delivered fresh for accurate diagnosis. The viability and DNA detection of B. hyodysenteriae using lab-made (phosphate buffered saline and modified tryptic soy broth) or commercial transport media (C, D, and E) were compared by culturing and real-time PCR at $4^{\circ}C$ or room temperature (RT), respectively. B. hyodysenteriae grown in D (Anaerobe Systems, USA) and E (Starplex Scientific, Canada) media was viable for 4 days at $4^{\circ}C$ and RT. However, B. hyodysenteriae in A, B, and C (culture swab; BD Biosciences, USA) media were not recovered after 2 days at RT. Ct values for real-time PCR at $4^{\circ}C$ and RT ranged from $27.2{\pm}2.1$ (C) to $29.6{\pm}0.5$ (B), and $28.0{\pm}0.9$ (E) to $30.2{\pm}1.5$ (B), respectively. Considering the field conditions, it is important that transport media is used for specimen isolation and PCR to obtain an accurate diagnosis of swine dysentery.

• Korean Journal of Veterinary Research
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• v.49 no.1
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• pp.45-57
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• 2009

The molecular genetic characterization of Aujeszky's disease virus (ADV) Yangsan strain (ADVYS), a Korean isolate, was investigated by analyzing the electrophoresis patterns and the physical maps of the viral DNA digested with various endonucleases. To establish DNA library for ADV-YS, twelve major BamHI restricted segments were cloned. Each location of the segments in the ADV genome was determined by sequence comparison with the sequences reported in Genbank and those sequences of the both termini of the segments. Physical maps were constructed based on the electrophoresis patterns of the digested viral DNA by restriction endonuclease and the results of Southern blot analyses with various DIG labeled probes originated from those of enzyme restricted segments of virulent (Shope) and avirulent (Bartha) strain. Comparing ADV-YS with a standard strain of Kaplan in the maps of restriction enzymes, following major respects were identified: (i) disappearance of BamHI restriction site between the first and second BamHI segments, (ii) creation of the BamHI restriction site in the fifth segment, and (iii) generation of the BglII site in the unique short (US) region. The genome of ADV-YS also contains a type 2 herpesvirus DNA molecule (in which the US region only inverts itself relative to the unique longregion) like all other ADV strains except Norden strain(type3), analyzed up to date. The size of the ADV genome estimated from the sizes of the restriction enzyme fragments, was approximately 145.3 kb (BamHI) or 145.4 kb (BglII). BamHI enzyme cleavage patterns were compared among the five Korean ADV isolates: Yangsan, Yongin, Dangjin, Jincheon and Iksan strains. Difference either in the number or in the size of the DNA fragments, suspected regions of termini of IR and TR, could be detected among all five strains.

• Korean Journal of Veterinary Research
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• v.48 no.1
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• pp.61-66
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• 2008

Akabane disease is caused by an arthropod-borne viral pathogen and leads to congenital abnormalities of the central nervous system in infected ruminants. One isolate, KV0505, showed cytopathic effect in Vero cells. The KV0505 isolate was obtained from plasma, which was collected from a cattle raised on Jeju Island in May 2005. Jeju Island is located near the southern part of the Korean peninsula. The isolate was confirmed as Akabane virus (AKAV) by immunofluorescence assay using AKAV specific monoclonal antibodies and reverse transcription polymerase chain reaction (RTPCR). Suckling mice inoculated with the isolate showed signs of paralysis and died within 10 days postinoculation. Comparisons of the KV0505 N gene sequence with 39 other known AKAV strains revealed nucleotide homologies ranging from 83.6% (MP496 strain) to 99.7% (M171 strain). When compared with the K-9 strain, which was isolated from a cow in Korea in 1994, the nucleotide sequence homology with the N gene was 99.7%. Thus, genes of the KV0505 isolate were closely related to those of the M171 strain, which were clustered into the Ic group of AKAV.

• Korean Journal of Veterinary Research
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• v.46 no.3
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• pp.271-274
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• 2006

A 2-years-old female domesticated mouflon with a clinical history of chronic diarrhea and emaciation was submitted to NVRQS. Grossly, there were severe thickening of small intestine wall and enlargement of mesenteric lymph nodes. Microscopically, severe granulomatous inflammation was found in small and large intestine, mesenteric lymph nodes, spleen and liver. By Ziehl-Neelsen stain, innumerable acid-fast rod bacteria were found in the cytoplasm of epitheloid and Langhans type giant cells present in these organs. By PCR assay with primer pair specific for Mycobacterium avium subspecies paratuberculosis(IS 900) with small intestine sample, strong positive reaction was detected, although the organism was not isolated from this organ. Based on the results of histopathology and PCR, we concluded that the case was a typical paratuberculosis in mouflon. As far as we know, this is the first case report of paratuberculosis in mouflon Korea.

• Korean Journal of Veterinary Research
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• v.54 no.4
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• pp.253-256
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• 2014

In this study, we describe a case of epitheliogenesis imperfecta (EI) observed in the fetus of Korean native cattle. The fetus had multifocal areas of skin defect, especially on the distal portions of the four limbs, and the affected areas were bright-red and glistening. Histopathologically, these areas were characterized by complete absence of squamous epithelium, infiltration of inflammatory cells into the dermis, atrophy of hair follicles, sebaceous and sweat glands. To the best of our knowledge, this is the first report of epitheliogenesis imperfecta in Korean native cattle.

• Korean Journal of Veterinary Research
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• v.55 no.2
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• pp.149-152
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• 2015

An abnormally enlarged right ovary and a mass in fat surrounding the right kidney were discovered in a dairy cow during routine postmortem examination at slaughter. The ovary was dark reddish and multinodular in shape. Numerous cystic structures were identified in the mass. Histopathologically, the ovary was completely replaced with large, uniform, polyhedral neoplastic cells containing vesicular nuclei and prominent nucleoli. The mitotic index was high. In the lymphatic vessels, tumor emboli were observed. Another mass in the fat surranding the right kidney had the same histological features as the ovarian mass. This animal was diagnosed with malignant dysgerminoma and metastasis to other peritoneal organs.

• Korean Journal of Veterinary Research
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• v.49 no.4
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• pp.291-295
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• 2009

A dead stray cat was necropsied for zoonotic feline disease monitoring. Grossly, there were no specific lesions. Major microscopic lesions included lymphocytic meningoencephalitis, malacia, and tissue cysts in the cerebral and cerebellar cortex. The size and shape of tissue cysts were identical to those of Apicomplexa including Toxoplasma (T.) gondii. Bradyzoites in the tissue cyst were strongly positive for T. gondii by immunohistochemistry. Electron microscopy revealed that bradyzoites within the tissue cyst were similar to the morphological features of T. gondii. Fresh tissue samples were examined by a polymerase chain reaction assay and resulted in a specific band of T. gondii only in the brain. Based on the results, this case was diagnosed as toxoplasmosis. This is the first case of toxoplasmic meningoencephalitis in a cat in Korea.

• Korean Journal of Veterinary Research
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• v.53 no.1
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• pp.29-35
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• 2013

To develop a live vaccine candidate using an attenuated strain of Salmonella Typhimurium (ST), biochemical properties, plasmid profile, PFGE patterns and pathogenic analysis of the ST isolate were carried out after sequential passage of the ST isolate in porcine neutrophils. By the passage, the ability of the neutrophil-adapted isolate to utilize d-xylose was lost, while the ability of the strain to ferment trehalose was delayed after 2 or more days of the culture. Also, changes including deletion of the gene fragments were observed in PFGE analysis of the neutrophil-adapted isolates. Two plasmids, 105kb and 50kb, were cured in the strain passaged over 15 times in porcine neutrophils. The 50% of lethal dose ($LD_{50}$) of the parent strain was changed from $1{\times}10^5\;LD_{50}$ to $6{\times}10^6\;LD_{50}$ by the passage in intraperitoneal injection of the strains into mice. These results suggested that bacterial genotypic and phenotypic responses might be globally altered depending on the inside environment of neutrophils.

• Korean Journal of Veterinary Research
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• v.48 no.2
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• pp.153-159
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• 2008

Newcastle disease virus (NDV) is the causative agent of a highly contagious and devastating Newcastle disease of poultry. A NDV (isolate DK1/07) was isolated from apparently healthy wild spot-billed ducks (Anas poecilorhyncha) captured at upper branch of the SapGyo Creek in Chungbuk province, Korea during early 2007. The DK1/07 isolate of minimum chicken embryo lethal dose killed all SPF chicken embryos within 60 h. The cleavage site of the F protein possessed the amino acid sequence $^{112}R-R-Q-K-R-F^{117}$, which is a motif characteristic of virulent NDV strains. The F protein-based phylogenetic analysis revealed that the DK1/07 duck isolate was included in the cluster of genotype VIId and most closely related to recent NDV isolates obtained from chicken farms in Korea. Epidemiological importance of virulent NDV from wild duck is discussed.

• Korean Journal of Veterinary Service
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• v.34 no.2
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• pp.103-109
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• 2011

Asia1/Shamir that has been recommended by World Reference Laboratory for foot-and-mouth disease (FMD) is used as a vaccine strain, and is being prepared in many countries including Korea. Although it is assumed that vaccine strain Asia1/Shamir has a wide antigenicity, sufficient molecular biological analysis has not been accomplished yet. Complete genome sequence analysis showed that the region with the most severe variations was 1D region of structural protein-coding sequence; particularly amino acid 141~157 residues in 1D region RGD sites for binding to susceptible cells. In addition, five amino acids in 1D region were identified as characteristic sites that are different from other known Asia1 viruses. Asia1/Shamir strain was shown to be genetically similar to group VI that had occurred in the Middle East, but showed low level of genetic similarity to the group V viruses that had occurred in the Southeast Asia and China. It is considered that, if these viruses, group I and II including group V are introduced into Korea, care would be paid in case of inoculating the vaccine strain Shamir available in Korea.