Doo Kim

Comparison of the pathogenicity in three different Korean canine parvovirus 2 (CPV-2) isolates

Canine parvovirus type 2 (CPV-2) is a major pathogen inducing acute hemorrhagic gastroenteritis in dogs. Despite the identification of numerous CPV-2 variants (from CPV-2a to CPV-2c), the pathogenic differences among the CPV-2 variants in dogs have not been evaluated. The aim of this study was to compare the pathogenicity of CPV-2 variants (CPV-2a-I, CPV-2a-V and CPV-2b) isolated mainly from Korea. We evaluated the pathogenicity of three different CPV-2 variants, by performing clinical, hematological, serological and histopathological examinations after experimentally inoculating three types of CPV-2 variants into young puppies. We found that the overall pathogenicity of the CPV-2a variants (CPV-2a-I and 2a-V) was severer compared to the CPV-2b variant. In addition, there was no significant difference in pathogenicity between the two CPV-2a variants. Our findings indicate that there are differences in the pathogenicity of CPV-2 variants in dogs, which may be useful to understand the different pathobiology of the CPV-2 variants.

M gene analysis of canine coronavirus strains detected in Korea.

The purpose of this study was to investigate the genetic features of canine coronavirus (CCV) strains detected in Korea. M gene sequences obtained for isolates from 22 dogs with enteritis over a 5-year period were evaluated. Sequence comparison revealed that the 22 Korean CCV strains had an 87.2 to 100% nucleotide homology. Comparing to the typical reference CCV strains (type II), the nucleotide sequence of Korean strains had homology ranged from 86.3% to 98.3% (89.1% to 99.2% for the amino acid sequence) and 87.7% to 97.8% (92.4% to 100% for the amino acid sequence) when compared to FCoV-like CCV strains (type I). Three amino acid variations in the M gene were characteristic for the Korean CCV strains. Phylogenetic analysis demonstrated that the 22 Korean CCV strains belonged to four typical CCV clusters (i.e., a unique Korean CCV cluster, a type II and transmissible gastroenteritis virus cluster, an intermediate cluster between type I and II, and a type I cluster). This study was the first to identify genetic differences of the M gene from Korean CCV strains and provided a platform for molecular identification of different Korean CCV strains.

Acute gastrointestinal dilation in laboratory rhesus monkeys in the Korea National Primate Research Center

Acute gastrointestinal dilation is a medical condition in which the stomach and intestine become overstretched by excessive gas content. In laboratory monkeys, cases of bloating involving gastrointestinal dilation are rarely seen, and the cause thereof is not clearly defined. Two rhesus monkeys in the Korea National Primate Research Center were found to suffer from acute gastrointestinal dilation. One of the monkeys showed severe gastric bloating after recovering from general anesthesia with isoflurane, where after it died suddenly. During necropsy, severe congestion of the lung was observed. The other monkey showed gastrointestinal dilation and died after treatment. During necropsy, severe dilation of the large intestine was observed. Severe congestion was detected in small and large intestines. Histopathologically, erythrocytes were found to fill the alveoli and alveolar capillaries of the lung. In stomach, epithelial cells were found to be sloughed from the mucosal layer, and erythrocytes were found to fill the blood vessels of the submucosal and mucosal layers. In small and large intestines, epithelial cells were also found to be sloughed from the mucosal layer, and inflammatory cells were found to have infiltrated in the submucosa (only large intestine) and mucosa. Microbiologically, Enterococcus faecalis and the pathogenic Staphylococcus haemolyticus, which do not form gas in the gastrointestinal tract, were detected in the gastrointestinal contents of both monkeys. These results suggest that the cause of the acute gastrointestinal dilation in these monkeys was not infection by gas-forming bacteria, but rather multiple factors such as diet, anesthesia, and excessive water consumption.