• Journal of fish pathology
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• v.23 no.1
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• pp.27-35
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• 2010

Pathogens on the cultured 579 rockfish, Sebastes schlegeli in the marine cage farms from Geoje and Tongyeong of the Southern sea were investigated from 2006 to 2008. The pathogens were detected throughout the year at 46.0~90.0% for 3 years and the detection rate was low with an average 58.1% in May and high with an average 81.5% in October. Bacteria only, bacteria-parasite mix and virus only were found in October and November as well as parasite only, whereas infection of parasite only was dominant in May when the temperature increased and in August when the temperature peaked. Of rockfish, Microcotyle sp. and Caligus sp. were dominant for parasitic disease, and Vibrio sp. and Streptococcus sp. were dominant bacteria. For virus, RSIV and VNNV were detected as dominant organisms. While no virus was detected in 2006, VNNV, VHSV and RSIV were detected in 2007 due to $1.5\sim2.0^{\circ}C$ higher temperature than 2006 in the summer season. For total prevalence by rockfish sizes, the highest was found at 50.0~87.1% in 11~15cm sizes and 50% was found in 30 cm size. Parasite showed a similar trend of 50.0~79.6% as the total prevalence. Prevalence for bacteria varied from 1.6% (for 10 cm group) to 23.8% (for 26 cm group) and higher virus prevalence of 21.5% was found from below 25 cm group.

• Korean journal of applied entomology
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• v.30 no.3
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• pp.212-218
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• 1991

Pathogenicity of Spodoptera exigua nuclear polyhedrosis virus (SeMNPV) against the host insect and 8 species of lepidopterous insects and cross infection of baculoviruses to third instar of S. exigua larvae were studied to determine as a biocontrol agent for S. exigua. The median lethal concentrations($LC_{50}$)of the SeMNPV to egg mass was $2.855\times10^5$ PIBs/ml and higher than that to the larvae of S. exigua. Mortality of the SeMNPV in third ins tar larvae was more increased than that in first and fifth instar of S. exigua larvae by 1.16 and 4.11 times, respectively. The median lethal times($LT_{50}$) to $1.56\times10^6$ PIBs/ml was in the range of 4.25 to 5.04 days. Infectivity of the SeMNPV against eight species of lepidopterous insects was showed only in the host insect, S. exigua. Autographa cali/ornica MNPV, Mamestra barassicae MNPV, and Trichoplusia ni MNPV were cross-infected to third instar of S. exigua larvae among ten of baculoviruses tested.

• Journal of the korean veterinary medical association
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• v.49 no.7
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• pp.424-429
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• 2013

• Journal of the korean veterinary medical association
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• v.31 no.10
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• pp.661-665
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• 1995

• Korean journal of applied entomology
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• v.30 no.3
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• pp.219-226
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• 1991

A cytoplasmic polyhedrosis virus isolated from the oriental tobacco budworm, Heliothis assulta (HaCPV), was studied on morphology of the polyhedron and virus particles, analysis of viral protein and nucleic acid, and bioassay of the HaCPV to determine the feasibility of application as a microbial control agent. The shape of polyhedron was hexagonal ranging 0.5-3.7 ${\mu}m$ and the virus particles were icosahedral outline measured 55 nm in diameter. Polyhedral protein was composed of a major polypetide of 24.3 Kd and 5 minor components and virus particle had seven polypeptides ranging in 28.0 Kd-133. 6 Kd by the SDS-P AGE. The genome of virus was segmented with 10 double stranded RNA in the total mol. wt. of 18.08 Md ranging in 0.65 Md -2.79 Md. The $LC_{50}$ values of the HaCPV to the 3rd instar of H. assulta larvae were calculated to $2.895{\times}10^5PIBs/ml$. The $LT_{50}$ values in the concentration of $5.0{\times}10^{6}PIBs/ml$ was 16.4 days.

• Journal of Sericultural and Entomological Science
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• v.17 no.2
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• pp.101-118
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• 1975

The pathogenicity of hexagonal and tetragonal cytoplasmic polyhedron virus to one of present leading silkworm varieties, Jam 103${\times}$Jam 104, and its parents, Jam 103 and Jam 104, was investigated. The activation of occult virus by oral inoculation of foreign virus as well as the interference phenomena between the activated and inoculated cytoplasmic polyhedron viruses was observed and the results obtained are as follows. 1. The pathogenicity of cytoplasmic polyhedrosis viruses. 1) There was a high significant difference in the pathogenicity of hexagonal polyhedron virus between the hybrid and its parents showing the lowest infection rate in the hybrid (Jam 103${\times}$Jam 104), medium infection rate in the Japanese line (Jam 103) and the highest infection rate in the Chinese line (Jam 104). In the pathogenicityof tetragonal polyhedron virus, a significant difference was observed only between the hybrid (Jam 103${\times}$Jam 104) and the Chinese line (Jam 104) by showing a higher infection rate in the Chinese line than in the hybrid. 2) The pathogenicity of both hexagonal and tetragonal polyhedron viruses showed a high significant difference in different silkworm instars inoculated by showing a higher infection rate at the second instar than at the fourth instar. 3) The pathogenicity of both hexagonal and tetragonal polyhedron viruses was increased as the concentration of viruses inoculated increased. 2. The phenomena of induction and interference by oral inoculation of foreign virus. 1) The induction rate of cytoplasmic polyhedrosis virus was higher in the parents than in the hybrid. In the parents. a higher rate in the Chinese line than in the Japanese line was observed. 2) The effect of inoculation at different instars on the induction was studied and the induction rate was higher at the second instar inoculated than at the fourth instar inoculated. 3) The degree of activation of hexagonal polyhedron virus with inoculation of tetragonal polyhedron virus was very high when a lower concentration of virus was inoculated and it was very low when a higher concentration of virus was inoculated 4) The degree of activation of tetragonal polyhedron virus with inoculation of hexagonal polyhedron virus was very low when a lower concentration of virus was inoculated and it was not observed when a higher concentration of virus was inoculated. 5) The mixed infection rate with hexagonal and tetragonal polyhedron viruses was higher at the second instar inoculated than at the fourth instar inoculated. 6) It was observed that the secondary hexagonal pc]yhedron virus activated interfered with the primary tetragonal polyhedron virus inoculated when the inoculated concentration of the primary virus is low and the primary virus inoculated interfered with the secondary virus activated when the inoculated concentration of the primary virus is high.

• 한국상하수도협회지
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• s.22
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• pp.50-51
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• 2008

미생물은 동전의 양면처럼 우리 삶에 유익하게 활용되기도 하지만 한편으로는 많은 질병의 원인체로 작용하기도 한다. 이러한 질병의 원인이 되는 세균, 바이러스, 원생동물 등이 물을 매개체로 할 경우 우리는 이를 수인성 병원미생물이라 일컫는다. 따라서 원수에 어떠한 종류의 미생물이 존재하고, 그 원수를 이용해 만들어지는 수돗물의 안전성에 대해 의문을 갖는 것은 당연한 일일수있다.

• Food Science and Industry
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• v.42 no.3
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• pp.8-13
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• 2009

• Korean Journal of Veterinary Research
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• v.37 no.4
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• pp.765-772
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• 1997

제주지역 돼지에서 각종 전염성 질병 원인체에 대한 항체를 조사하여 그간 전염성 병원체에 대한 역학조사가 미진하였던 부분을 보완하여 질병의 분포를 파악하고자 1995년부터 1996년에 걸쳐 제주도 전역에서 돼지의 혈청을 채취하여 각종 병원체에 대한 항체 분포율을 조사하였다. 본 연구에서 검사한 돼지 혈청 시료에서는 돼지 오제스키병 바이러스에 대한 항체는 전혀 검출되지 않았다. 돼지 콜레라바이러스에 대한 항체는 기대 수준 이하로 낮아 백신접종이 원활히 수행되고 있지 않음을 시사하였으며 특히 농장에 따라 항체 보유돈과 항체 음성돈이 혼재하는 농장과 항체가 전혀 검출되지 않는 농장 등 돼지 콜레라 방역의 사각지대가 존재할 가능성이 있음을 보여주었다. 유 사산 원인체인 돼지 파보바이러스 및 뇌심근염에 대한 항체가가 다양하게 나타나 일부 문제가 있을 것으로 사료되었다. 돼지 생식기호흡기증후군(PRRS) 바이러스에 대한 항체 분포율은 내륙 보다 다소 낮게 나타났고, 돼지 influenza virus, 위축성 비염, 흉막 폐염 등 각종 세균성 질환에 대한 항체수준도 다양하게 나타났다. 본 혈청학적인 연구결과는 제주지역에서의 양돈방역 정책수립 및 질병방제의 기초자료로 유용하게 이용될 것으로 사료된다.

• Korean journal of applied entomology
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• v.27 no.4
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• pp.219-224
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• 1988

Rearing of Spodoptera litura fed on arfificial diet basically formulated with kindby bean powder was much promisible for production of S. litura nuclear polyhedrosis virus(SINPV) than that on kidney bean leaves. The $LC_{50}$ of SINPV against 3rd and 5th instar were $4.48{\times}10^{3}$ PIB/ml and $4.52{\times}10^{4}$ PIB/ml, respectively. The $LC_{50}${/TEX} of SINPV varied from 5.8 days to 7.7 days at higher inocula in the testes. The larval growth of 1st and 3rd instar larvae fed on virus were much delayed and the larval were killed within 4th instar in the former and within 5th instar in latter. S. litura larvae were very susceptible to multinucleocapsid nuclear polyhedsosis virus (MNPV) of Autographa californica, S. littoralis and Trichoplusia ni.