• Korean Journal of Veterinary Research
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• v.40 no.1
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• pp.110-116
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• 2000

Duck viral hepatitis is an acutic, highly infectious viral disease of young ducklings. The most practical means for controlling duck viral hepatitis is the vaccination of ducklings or of a breeding stock. We attempted to develop a vaccine strain of duck hepatitis virus (DHV) using a Korean isolate by serial chicken embryo passages. The propagation of DHV in chicken embryos was carried 140 passages. After the $50^{th}$ passage, of which the virus was non-pathogenic for ducklings, approximately every $20^{th}$ passage of the virus was tested for vaccinal efficacy. Both the $70^{th}$ and $90^{th}$ passage of the virus gave good protection against challenge infection to a DHV-DRL reference strain(type 1) and a virulent Korean isolate. The $110^{th}$, $125^{th}$ and $140^{th}$ passage of the virus were less protective than the $70^{th}$ and $90^{th}$ passage, which means that more than $110^{th}$ passage may lead to over-attenuation of the virus. Ducklings vaccinated with the chicken-embryo-adapted virus by oral, intramuscular or eye drop administration showed earlier resistance to challenge infection from 3 to 7 days postvaccination. Of the above methods, ducklings vaccinated intramuscularly presented the most rapid resistance against challenge. The minimum immune dose of the chicken-embryo-adapted virus in ducklings was also studied. Ducklings inoculated with a dose of $10^{2.0}\;ELD_{50}$ and below were not fully protected against challenge with a virulent DHV, showing a protection rate of 67% to 73%, but ducklings inoculated with a dose of $10^{3.0}\;ELD_{50}$ and over were completely protected. The virus yield of the chicken-embryo-adapted DHV was examined at 24hrs and 48hrs of the incubation time in the allantoic fluid, embryo head and embryo minus head of the embryonating egg. In all three components, the titer of the virus was higher at 48 hours than that at 24 hours after incubation. And the titer of the virus was higher in the embryo minus head, embryo head and the allantoic fluid, in order. Field trials for evaluating the efficacy of the attenuated DHV as a live vaccine were done in duck farms with about 25% mortality of flocks resulting from duck viral hepatitis. After the use of the experimental vaccine, the mortality due to duck viral hepatitis was dramatically reduced in the farms. These results indicated that the attenuated DHV using a Korean isolate could be a good candidate as a live vaccine strain of DHV in Korea.

• Korean Journal of Veterinary Pathology
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• v.5 no.2
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• pp.43-48
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• 2001

Ducklings collected from three farms, having history of rapid onset and spread of nerve signs including kick spasmodically with legs and opisthotonos, were pathologically, barteriologically, virologically examined. Grossly, multiple petechial to ecchymotic hemorrhages were detected in the swollen liver. Histopathologically, diffuse coagulative necrosis of hepatocytes was characteristic in acute cases. Chronic cases revealed marked bile duct hyperplasia rather than hepatocyte necrosis. Some of these cases exhibited multiple granulomas consisting of macrophages, heterophil, fibrin and necrotic cell debri. Filtered homogenate of livers sampled from ducklings caused embryo death with marked hemorrhage and swollen of liver after inoculation into chorioallantoic membrane. Three strains of Salmonella app.,S montevideo, S hadar, and S give, which were biochemically and serologically identified, weir isolated from ducklings of three farms, respectively. From these results, these ducklings were concurrently infected with duck hepatitis virus and Salmonella spp.

• Korean Journal of Veterinary Research
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• v.40 no.1
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• pp.101-109
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• 2000

Duck viral hepatitis is an acute, highly infectious viral disease of young dacklings aged from two days to three weeks. The significant lesion associated with the disease was enlarged liver including necrotic foci and numerous hemorrhagic spots. We have isolated five strains of duck hepatitis virus (DHV) from field cases showing about 20% mortality with a sign of opisthotonos. When a-day-old ducklings were intramuscularly inoculated with one of the isolates, 92% of the birds were died within 5 days. We attempted to develop an attenuated strain of duck hepatitis virus (DHV) using one of the isolates by serial chicken embryo passages. The propagation of DHV in chicken embryos was carried 140 passages. The virus titer increased gradually from the $21^{st}$ through the $50^{th}$ passage, but there was no significant increase of virus titer in subsequent passages after then. Through the serial passages, the virulence of the virus for chicken embryos was gradually increased but decreased for ducklings. The pathogenicity of the virus for ducklings was preserved up to the $21^{st}$ passage but disappeared at the $50^{th}$passage. An attenuated Korean isolate which was passaged 140 times in chicken embryos gave good protection in ducklings against both challenge infection to a Korean virulent strain and to a DHV-DRL strain, a type 1 reference strain of DHV, which indicated that the Korean isolates could be classified as DHV type 1. And the above results suggest that an attenuated Korean isolate can be used for developing a live DHV vaccine.

• The Journal of Internal Korean Medicine
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• v.22 no.3
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• pp.291-298
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• 2001

Objectives : This study was conducted to evaluate the effects that Injinsugunomija Extract affected Liver function test of Alcoholic liver disease and Viral hepatitis patients. Methods: We adminstered eighty packets of Injinsugunomija Extract to some kinds of liver disease patients for one month. And we investigated the changes of their liver function test. Results: The results from this study were summarized as followed. In the 10 patients of Alcoholic Liver Disease (ALD), 3 cases improve prominent and 4 cases improve effective and 3 cases are ineffective. Then 70% 01 ALD patients has improved by Injinsugunomija Extract In the 9 patients of Viral hepatitis, 1 case improves prominent and 4 cases improve effective and 1 case become worse and 1 case become worst and 2 cases are ineffective. Then 55.6% of Viral hepatitis patients has improved by Injinsugunomija Extract. Conclusions: From these results, Injinsugunomija Extract showed the meaningful effects on improving liver function test of ALD patients and Viral hepatitis patients.

• Korean Journal of Veterinary Service
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• v.36 no.1
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• pp.61-65
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• 2013

We investigated the prevalence of infectious duck diseases using 156 ducks reared in 18 farms of western Gyeong-nam province. As a result, duck viral hepatitis (12.8%), colibacillosis (7.1%), and fungal disease (9.0%) were detected. However, avian influenza and riemerellosis were not detected. During autopsies, we could grossly observed red swollen liver (12.8%), petechial or ecchymotic hemorrhage on liver (11.5%), and fibrinous perihepatitis (9.0%). Gray-white necrotic spot (23.1%), swollen spleen (22.8%), swollen kidney (20.5%), hyperemia or hemorrhage on tracheal mucous membrane (8.3%), and nodule in long or air sac (9.0%) were also found.

• Toxicological Research
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• v.13 no.4
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• pp.327-330
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• 1997

Hepatitis, liver cirrhosis and liver cancer caused by viral infection are among the most prevalent causes of death in Korea. Several medicines have been in use despite their nonsatisfactory effects on these disease. Some herbal medicines put to use recently have not shown beneficial effects, either. This paper evaluates the effects of extracts from 10 traditional Korean herbal medicines on rats with hepatic damage induced by galactosamine. Rubus coreanus showed an anti-inflammatory effect as shown on the data of activities of serum transaminases.

• Korean Journal of Veterinary Service
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• v.20 no.4
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• pp.323-329
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• 1997

An outbreak of duck septicemia caused by Pasteurella anatipestifer was studied in Chonnam province. The outbreaks of duck septicemia has become an economically important disease in duck farm. The present study undertaken to identify the etiological agent of duck septicemia and to evaluate the efficacy of bacterin against P anatipestifer in Chonnam province during period from May to December 1996. The results obtained were as follows ; 1. The distribution of etiological agents from collected 328 duck samples were Pasteurella anatipestifer(57%), Escherichia coli(21%), duck viral hepatitis virus(4%), Salmonella sp(1%) and others (10%). 2. The agglutination titers of autogenous vaccine were increased after End vaccination and reached highest at 5-6 weeks post inoculation at the titers of 6.0-4.0.

• Clinical and Experimental Pediatrics
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• v.51 no.11
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• pp.1191-1197
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• 2008

Purpose : Previously, Epstein-Barr virus (EBV) infection was diagnosed by serological examination; currently, many EBV antigen detection methods have been developed and applied clinically for diagnosing EBV infection. To delineate the clinical characteristics of EBV infection, clinical and laboratory findings were evaluated for patients who tested positive in EBV polymerase chain reaction (PCR). Methods : EBV PCR was conducted in 352 patients admitted to the pediatric ward from January 2004 to December 2006, with more than 2 clinical signs such as fever (${\geq}37.5^{\circ}C$), exudative throat infection, lymphadenopathy, hepatitis of unknown etiology, and splenomegaly. The EBV viral gene was detected by PCR in 115 patients (32%), and the clinical characteristics of these patients were evaluated. Laboratory findings such as leukocytosis, thrombocytopenia, atypical lymphocyte, and alteration in aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels in peripheral blood were examined. The EBV-specific immunoglobulin M antibody (EBV-IgM Ab) was also tested. Results : Most of the children were younger than 8 years (89%), and the male to female ratio was 1.3:1. Exudative throat infection and fever (${\geq}37.5^{\circ}C$) were observed in all patients. Cervical lymph node enlargement was seen in 36 patients (31 %); leukocytosis ($WBC{\geq}10,000/mm^3$), in 54 patients (47%); and atypical lymphocyte (${\geq}20%$), in 28 patients (24%). EBV-IgM Ab was positive in 33 patients (29%). The younger patients had higher ALT levels and higher incidence of positive EBV-IgM Ab than the older patients. Conclusion : The cumulative number of patients diagnosed to have EBV infection by PCR increased markedly for those under 8 years. ALT was higher and EBV-IgM Ab was detected more in younger patients with EBV infection.