• Korean Journal of Veterinary Research
• /
• v.29 no.2
• /
• pp.99-108
• /
• 1989

In order to observe the pathological changes of kidney in rabbits infected with the viral haemorrhagic disease, the kidney tissues from the 91 rabbits infected with the viral haemorrhagic disease were examined by light and electron microscopy. The results observed were as follows: 1. On light microscopic observation, the kidney lesions were identified as haemorrhagic glomerular necrosis(33.0%), membranous glomerulonephritis(20.9%), thrombotic glomerulopathy(19.8%), membranoproliferative glomerulonephritis(8.8%), mesangial proliferative glomerulonephritis(8.8%) ischemic acute tubular necrosis(7.7%), and acute serous glomerulitis(6.6%). 2. On electron microscopic observation, cytoplasmic degeneration of mesangial cells, and irregular thickening of basement membranes with electron dense granular materials were observed. In podocytes swelling of mitochondria, dilatation of endoplasmic reticulum and extensive fusion of foot processes were also observed. Nonenveloped round icosahedral picornaviral particles with a diameter of 28~33nm were detected in the cytoplasm of degenerative endothelial cells, polymorphonuclear leucoytes, and monocytes.

• Biomedical Science Letters
• /
• v.2 no.2
• /
• pp.257-265
• /
• 1996

Simple stain and electron microscopic in situ hybridization is studied and applied for the identification of rabbit haemorrhagic disease viral RNA in a unicrylated preparation of the liver after innoculation of rabbit haemorrhagic disease virus. Hybridization for detection of viral RNA in unicryl embedded tissues using complementary 84 bases oligonucleotide probe labelled by biotin CE-phosphoramidite compared with 4717∼4800 sequences of rabbit haemorrhagic disease virus, modified hybridization protocol and antibiotin antibody-l0nm gold as signal marker. The best results were obtained in 0.02% glutaraldehyde, Unicryl resin cell block, biotinylated oligonucleotide probes, antibiotin-l0nm gold. In this report, RHD viral RNA was distributed widely within the mitochondria and nucleus of liver cell by electron microscopic in situ hybridization. In situ hybridization has become a standard method for localizing DNA or RNA sequences in tissue or celt preparation. In situ hybridization is detected the virus genome in the cells and tissue as specifically compared with others nucleic acid hybridization method.

• Journal of fish pathology
• /
• v.26 no.3
• /
• pp.149-161
• /
• 2013

Viral haemorrhagic septicaemia virus (VHSV), the causative agent of viral haemorrhagic septicaemia (VHS), is an epidemic virus of cultured olive flounder Paralichthys olivaceus in Korea. In the present study, the entire glycoprotein (G) gene including several hypervariable regions from 36 isolates of diverse geographic and host origin and 8 Korean VHSV isolates from cultured olive flounder were analyzed. Phylogenetic analysis indicated that most of Asian VHSV belong to the genotype IVa group, suggesting that they originated from a common ancestral virus. Comparative sequence analysis of the complete G protein from Korean VHSV isolates revealed 3 Korean strain-specific nucleotide residues (nucleotide number of G-region: A755, T834 and T1221). These results suggest that Korean VHSV originated from a common ancestor, but these regional specific nucleotide sequences suggest that genetic differences of VHSV are more related to geographic areas than to host fish species.

• Korean Journal of Veterinary Research
• /
• v.33 no.1
• /
• pp.125-129
• /
• 1993

An acute fatal infectious disease in rabbits has been outbroken in Korea since 1985. This disease has been characterized as an acute hepatitis caused by viruses. However, viral pathogenesis in rabbit viral hepatitis leading to sudden death remain unclear. This report dealt with the electron microscopic findings on the spleen of experimentally infected rabbits, because spleen is one of the affected organs which have high titer of virus by a haemagglutination test. A typical crystalline array of virus was not found in the splenic cells of infected rabbits with acute hepatitis. Virus-like particles were seen within the phagosome of macrophages of the spleen. Ultrastructural changes in the spleen were severe with the lapse of time after inoculation. From these results, virus-like particles in the spleen were supposed to be phagocytosed by macrophage during viremia, while active replication of virus occurred in the liver. It was concluded that sudden death in this viral disease was caused by hepatic coma and/or circulatory disturbance.

• Journal of the korean veterinary medical association
• /
• v.23 no.9
• /
• pp.603-610
• /
• 1987

The pathological and microbiological studies were carried out to investigate an acute, febrile, highly fetal, infectious disease of rabbits that had occurred in the Winter and in the Spring and that had begun to be reported in Korea from November, 1985. The clinical signs of this disease were characterized by high fever, lethargy, piercing shriek, convulsion, and sudden death with epistaxis, but often they were not observed. The predominant pathogical findings were severe congestion and hamorrhage in trachea, dark brown discoloration of liver by diffuse necrosis or acute viral hepatitis, and hamorrhagic damages of lung, heart, spleen, kidney, etc. The etiological agent was a small round virus, in 25-35nm in diameter and without envelope, thus looking like a picorna virus. This disease resembled what was called the 'Viral Hamorrhagic Pneumonia in Rabbits'(tentative name) that had been reported for the first time in China in 1984. It will be desirable that the disease should be renamed as the 'Viral Hemorrhagic Fever in Rabbits', the 'Acute Viral Hepatitis in Rabbits', etc. because of its charateristics and the basis of pathological findings. An inactivated vaccine is now in the process of preparation for the prophylaxis of this viral disease.

• Korean Journal of Veterinary Research
• /
• v.32 no.3
• /
• pp.399-402
• /
• 1992

The causative virus causing rabbit hepatitis has been further characterized by evaluating viral proteins and viral nucleic acids of purified viruses from the liver of the experimentally infected rabbits. Rabbit hepatitis virus has one major structural protein of 54 kilodaltons and some minor proteins. Vrial RNA was resistant to DNAse I. The size of viral nucleic acid of this virus was calculated to be about 7.5 kilobases. These findings indicate that rabbit hepatitis virus belongs to the family Caliciviridae.

• Journal of fish pathology
• /
• v.24 no.2
• /
• pp.121-129
• /
• 2011

Aquatic animal raised in hatcheries play an important role in supplying seedling to stock enhancement and seed quality, especially, seed health is the key factor for survival in the field after release and for stocking effectiveness. We have inspected the hatchery-reared seeds of 33 marine species and 12 freshwater species for legally designated diseases in stock enhancement program in 2010. Results showed that abalone was the most abundant as 20.0% in the marine species group and then sea cucumber (15.6%), olive flounder (8.4%), rockfish (6.7%), black sea bream (6.3%) and swimming crab (6.1%) were followed. Crucian carp was the most abundant as 19.4%, and then eel (11.8%), Korean bullhead (10.9%), mandarin fish (10.8%), melanian snail (8.4%), catfish (7.7%) were followed in the freshwater species group. The total number of inspection cases for eight pathogens in this study were 2,105 and disqualification cases were 30 by detection of aquatic animals pathogens such as koi herpesvirus (KHV), red sea bream iridovirus (RSIV), white spot syndrome virus (WSSV) or viral haemorrhagic septicemia virus (VHSV).

• Journal of fish pathology
• /
• v.26 no.2
• /
• pp.99-110
• /
• 2013

Hatchery-reared seeds provides a key source of animal protein for human consumption and restocking for fishery management. For stock enhancement program, we have inspected the hatchery-reared seeds of 33 species in 2009, 44 species in 2010, 43 species in 2011 and 46 species in 2012 for legally designated diseases. Results showed that abalone was the most abundant in the marine species group and then sea cucumber, olive flounder, rockfish and swimming crab were followed. Crucian carp was the most abundant and then mandarin fish, Korean bullhead, melanian snail and Chinese mitten crab were followed in the freshwater species group. The number of inspection for black sea bream, rock bream, scorpionfish, black scraper, and eel has continuously decreased for four years. The inspection for flathead mullet has been carried out only in 2009. The total number of inspection cases for eight pathogens in this study were 8,476 and disqualification cases were 56 (0.67%) by detection of aquatic animals pathogens such as koi herpesvirus, white spot syndrome virus, red sea bream iridovirus or viral haemorrhagic septicemia virus.

• Proceedings of the KSRS Conference
• /
• 2005.10a
• /
• pp.774-777
• /
• 2005

Dengue Fever(DF) and Dengue haemorrhagic fever(DHF) has become a major international public health concern. Dengue Fever(DF) and Dengue haemorrhagic Fever (DHF) is also still the major health problem of Thailand, although many campaigns against it have been conducted throughout the country. GIS and Remotely Sensed data are used to evaluate the relationships between socio-spatial, environmental factors/indicators and the incidences of viral diseases. The aim of the study is to identify the spatial risk factors in Dengue and Dengue Haemorrhagic Fever in Sukhothai province, Thailand using statistical, spatial and GIS Modelling. Preliminary results demonstrated that physical factors derived from remotely sensed data could indicate variation in physical risk factors affecting DF and DHF. The present study emphasizes the potential of remotely sensed data and GIS in spatial factors affecting Dengue Risk Zone analysis. The relationship between land cover and the cases of incidence of DF and DHF by information value method revaluated that highest information value is obtained for Built-up area. A negative relationship was observed for the forest area. The relations between climate data and cases of incidence have shown high correlation with rainfall factors in rainy season but poor correlation with temperature and relative humidity. The present study explores the potential of remotely sensed data and GIS in spatial analysis of factors affecting Dengue epidemic, strong spatial analysis tools of GIS. The capabilities of GIS for analyst spatial factors influencing risk zone has made it possible to apply spatial statistical analysis in Disease risk zone.

• Journal of Fisheries and Marine Sciences Education
• /
• v.27 no.3
• /
• pp.879-889
• /
• 2015

The outbreak of viral diseases caused by viral haemorrhagic septicaemia virus (VHSV) and red seabream iridovirus (RSIV) have been reported in cultured olive flounder, Paralichthys olivaceus. VHSV has been a serious viral disease that infects the olive flounders in South Korea. Clinical signs of VHSV infection are skin darkening, abdominal distension and haemorrhages. Outbreaks of fish iridoviral disease was first reported from red seabream, Pagrus major farms in Japan. Recently, iridovirus infection have occurred frequently from olive flounder farms in South Korea. In this study, disease surveillance was performed to monitor the prevalence of VHSV and RSIV in olive flounder in 2014. The samples were collected from 60 different olive flounder farms in Jeju from April, May, September, November and December in 2014. RT-PCR (VHSV) or PCR (RSIV) results showed that VHSV were detected in 5 farms, but RSIV has not been detected in any farms. The migration of olive flounder was restricted for the quarantine in 5 farms of VHS outbreak. The nucleocapsid protein (N) gene and glycoprotein (G) gene sequences of the 5 Korean VHSV isolates were successfully amplified and sequenced. Phylogenetic analysis was performed using the VHSV sequences reported here together comparison with the nucleotide sequences available from the GenBank database. Phylogenetic analysis indicated that most of Korea VHSV belong to the genotype IVa and closely related to the strains from Japan and China.