• Korean Journal of Veterinary Research
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• v.40 no.3
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• pp.587-599
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• 2000

This study was conducted to observe the severity of the disease and pathogenecity of Babesia gibsoni parasite on the splenectomized dogs(SPD) and nonsplenectomized(intact) dogs (NSPD) experimentally infected with B gibsoni. The average prepatent period was 4 days in the SPD and 8 days in the NSPD, respectively. Peak parasitaemia(PE) ranged from 26% to 34% of erythrocytes infected in the SPD and from 4% to 5% in the NSPD. Latent parasitaemia was still detectable 40 days as low as under 1.0% of erythrocytes infected after the initial parasitaemia in the SPD. Blood packed cell volume(PCV) decreased to as little as 6.4% to 6.9% in the SPD. The clinical signs were mild fever and anemia in the NSPD, remissions and exacervations of temperature, intermittent or spike-like increases of temperature, progressive polychromatophilic macrocytic anemia with anisocytosis, icterus, marked loss of appetite, rarely haemoglobinuria, and deep brown-yellowish urine in the SPD. Gross pathologic changes mainly involved slightly enlargement of liver and spleen in the NSPD and marked enlargement of liver in the SPD. Anatomic changes associated with the disease included diffuse periportal and centrilobular hephatitis, and membranoproliferative glomerulonephritis. Hyaline droplets, resulting protein metabolic alterations, were found in the convoluted ephithelium of the kidney. The density of lymphocytes within the liver sinusoids was markedly increased. Aggregates of large monocytes and macrophages were demonstrated in the centrilobular veins of the liver. The density of these cells in the centrilobular veins were greatest in the SPD. The forms of B gibsoni parasite found in the acute stage of SPD were large signet ring form, small signet ring form, pyriform, elongated form, comma form, head-phone form, oval form, peared form, racket-like form, amoeboid form, triangle form, quartered form, dot form, band form and multiple, and rosette form, et al. The severity of the disease and pathogenecity of B gibsoni parasite were mild in the NSPD but fatal in the SPD.

• Korean Journal of Microbiology
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• v.9 no.2
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• pp.69-73
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• 1971

On June in 1970 the authors discovered a pathogenecity, cytoplasmic polyhedrosis virus, of the Smithia virus in the larvae of Liparis dispay L. appeared on quercus forest in Chung-Neung district and had carried out a experiment to detect the pathogenecity of Smithia virus through the inoculation of it into the larvase, such as Liparis dispay L. Hyphantrea cunea DRURY, and Dendrolinus spectabilis BUTLER. The results obtained were as follows ; 1) Death rate of L.dispay and D.spectabilis treated by 10$^{6}$ /ml cytoplasmic polyhedrosis virus of Smithis virus were 88.0% and 85.5% respectively, when the larvaes of these insects are big enough. But there were none of pathogenecity in case of Hyphantrea cunea DRURY. 20 Dead larvae caused by the injection of Smithia virus had begum to find out about on 10 days after inoculation. Miximum death rate of L. didpay and D. spectabilis appeared on 20-25days nad on 25-30days, respectively, after the incoulation. 3) In the cytoplasm of Mid-gut cylindrical cells of both of these insects, polyhedrosis, such s hexagonal (0.5-2.0-6.0 micron) were found out and in these insects, polyhedrosis, such as hexaginal (0.5-2.0-6.0 mivton) were found out and in case of D.spectabilis were a few polyhedrosis, such as tetragonal, trianglar polyhedrosis. 4) Diluted concentration of `0$^{6}$ /ml cytoplasmic polyhedrosis virus of Smithia virus were spread out in the field conditions. The corrected mortality was confirmed as about 87.8%.

• Microbiology and Biotechnology Letters
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• v.22 no.3
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• pp.246-251
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• 1994

Pseudomonas syringae pv. tabaci(Pa45) Tox$^{-}$ cells were infected with phage Ps90 strain isolated form the natural source, and the Ps90 lysogenized bacterial cells were then obtained. The lyxohenized cells produced tabtoxin and the phage induction occured when the cells treated with mitomycin C. The Southren hybridization alnalysis of the four EcoRI-treated plasmid fragments and the EcoRI-digested genomic DNA of Tox$^{+}$ and Tox$^{-}$ strains using phage DNA as a probe showed that only those DNA fragment of Tox$^{+}$ strain were related to the Ps90 phage DNA. Based on these results, the tabtoxin producing DNA fragments of the bacteris are presumed to have originated from the same phage DNA, and to be responsible for the pathogenecity of the bactrial strains.

• Proceedings of the Microbiological Society of Korea Conference
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• 2005.05a
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• pp.172-172
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• 2005

• Journal of fish pathology
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• v.28 no.3
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• pp.145-155
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• 2015

The pathogenecity of atypical Aeromonas salmonicida was studied in healthy Oreochromis niloticus. Inoculum at concentration of $1.5{\times}10^8CFU/ml$ and $3{\times}10^8CFU/ml$ was injected into healthy fish through intramuscular and intraperitoneal injections. Experimentally infected Oreochromis niloticus showed ulceration at the dorsal musculature and trunk region in addition to black coloration, congested gills, exophthalmia, and ocular hemorrhage. Congested liver and kidney were recorded in post-mortem examination. Mortality of the experimentally infected Oreochromis niloticus reached 100% after intramuscular injection at concentration of $3{\times}10^8CFU/ml$. Histopathological investigation of infected organs was also performed. There was a focal area of bundles of skeletal musculature showing hyalinization. In addition, hyperplasia, congestion, and fusion were noticed in the gill lamellae. There was also congestion in the blood vessels in the ocular chamber. Severe congestion was also noticed in the central vein of liver associated with focal aggregation of the melanin pigmented cells in the parenchyma. Degenerative changes were noticed in the epithelial cells lining of kidney tubules. Plant extracts carvacrol and its biological precursor cymene were found to be effective in treating experimentally infected Oreochromis niloticus at concentration of 100 or 200 ppm.

• Journal of the korean veterinary medical association
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• v.15 no.3
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• pp.149-155
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• 1979

One hundred and fifteen strains of Escherichia coli were isolated' from suckling piglets of sow fed on food-garbage and their hemolytic property on horse red blood cells, necrotizing activity in rabbit skin and inflammatory activity in rabbit intestine by

• Journal of Sericultural and Entomological Science
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• v.24 no.1
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• pp.32-38
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• 1982

The study has been carried out to investigate a possibility to control the pine needle gall midge, Thecodiplosis japonensis Uchida et Inoue, by microbial pathogens as one of the microbial control measures. The samples were collected at Kocheon-Ri in the suburbs of Suweon city where were heavily damaged by this pest. Microorganisms were isolated from the both of diseased larvae and baiting method of soil microbes. In addition to, several species of the silkworm mucardine diseases were isolated for their infectivity of these fungi to the larvae of pine needle gall midge. Six species of fungi, Aureobasidium pullulans, Ascochyta sp, Verticillium psalliotae, Streptomyces sp., and two species of Aspergillus were isolated from the galls and soils, five species of muscardine diseases, Isaria farinosa, Spicaria pracina, Oospora destructor, Aspergillus flavus and A. oryzae were also identified from the silkworm corpse collected in the silkworm rearing farmers. Total of eleven species of fungi identified from the both of the larval of pine needle gall midge and silkworm larvae were tested for their pathogenecity to the larvae of pine needle gall midge. All of eleven species of fungi identified showed a considerable infectivity to the larvae. Twenty nine different kinds of bacteria were isolated from the both of diseased larvae and infested soils through the direct planting for the larvae and streaking for the corpse. The infectivity test is in progress. However two kinds of bacteria were recognized to be pathogenic to the larvae tested.

• Plant Disease and Agriculture
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• v.5 no.2
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• pp.119-121
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• 1999

A destructive collar rot of safflower occurred severely research farm of at Kyongsangnam-do Agricultural Research and Extension Services in 1999. Incidence of the disease at 3 fields in Chinju was ranged from 21.6 to 34.2% Upper parts of infected stems were mostly blighted and white mycelia were found on the lesions. The same fungus was isolated consistently from the infected tissues and confirmed its pathogenecity to safflower. The causal fungus of collar rot disease was identified as Sclerotium rolfsii by the examination of colony type sclerotium formation and pathogenicity test. This fungus also causes stem rot crown rot wilt or blight on the safflower. This is the first report on the collar rot of safflower caused by Sclerotium rolfsii in Korea.

• Research in Plant Disease
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• v.7 no.3
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• pp.145-149
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• 2001

A pathogenic bacterium was isolated from galls on Wistaria floibunda at Jinryang of Kyungsan, Kyungbuk, Korea in May, 2000. This bacterium was cultured and tested for pathogenicity on the host. Also its morphological and physiological characteristics were examined. Inoculation with the bacterium isolated from the gall caused the same symptoms as those under natural conditions. On the basis of bacteriological characteristics and pathogenecity on the host plant of the organism, the causal bacterium was identified as Pantoea agglomerans pv. milletiae. This is the first report of this bacterium to occur on W. floribunda plant in Korea. Therefore we proposed to name the disease as "bacterial gall of Wistaria floribunda" by P. agglomerans pv. milletiae.milletiae.

• Journal of Sericultural and Entomological Science
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• v.20 no.2
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• pp.36-39
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• 1978

With the current advances in insect toxicant bioassay, the need for easy methods of estimating the dosage-mortality regression equation has become vital. The Probit analysis seems to be not convenient for estimating the dosage-mortality regression equation and median lethal dose(LD50) because of its complexity in calculation. This study presents a comparision between Probit and Losit transformation for the estimation from bioassay results. Validation of the two methods is presented for the pathogenecity of nuclear polyhedrosis virus to the larva of fall web worm, Hyphantria cunea D.