• 생명과학회지
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• 제19권8호
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• pp.1170-1176
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• 2009

Porcine reproductive and respiratory syndrome virus (PRRSV) has plagued pig populations worldwide causing severe economical impacts. In order to establish effective strategies for prevention of PRRS, infection patterns on the herd level are primarily evaluated. In the present study, therefore, serological and virological analyses were conducted in 20 pig farms suffering from PRRS. Seroprevalence levels in each farm were grouped into 3 patterns: SN (Stable sow groups/Not infected piglet groups, SI (Stable sow groups and Infected piglet groups), and UI (Unstable sow groups and Infected piglet groups). The rates of each serological pattern were 15% (n=3), 10% (n=2), and 75% (n=15), respectively. In addition, the pattern analysis was extended to virological monitoring on the same farms that further included suckling pig groups. As a result, the infection pattern was classified into 4 categories: SNI (Stable sow groups/Not infected suckler groups/Infected piglet groups), SII (Stable sow groups/Infected suckler groups/Infected piglet groups), UNI (Unstable sow groups/Not infected suckler groups/Infected piglet groups), and UII (Unstable sow groups/Infected suckler groups/Infected piglet groups). The rates of each viroprevalence were estimated at 50% (n=10), 30% (n=6), 10% (n=2), and 10% (n=2), respectively. PRRSV viroprevalence results of suckling pig groups revealed that 8 farms were considered virus positive. In 2 farms among these farms, PRRSV appeared to be transmitted vertically to suckling piglets from their sows. In contrast, piglet-to-piglet horizontal transmission of PRRSV seemed to occur in sucking herds of the remaining farms. Thus, this virological analysis on suckling piglets will provide useful information to understand PRRSV transmission routes during the suckling period and to improve a PRRS control programs. Our seroprevalence and viroprevalence data found that infection patterns between sow and piglet groups are not always coincident in the same farm. Remarkably, 15 farms belonging to the UI seroprevalence pattern showed four distinct viroprevalence patterns (SNI; 7, SII; 4, UNI; 2 and UII; 2). Among these farms, 11 farms with unstable seroprevalence sow groups were further identified as the stable viroprevalence pattern. These results indicated that despite the absence of typical seroconversion, PRRSV infection was detected in several farms, implying the limitation of serological analysis. Taken together, our data strongly suggests that both seroprevalence and viroprevalence should be determined in parallel so that a PRRS control strategies can be efficiently developed on a farm level.

• 한국응용곤충학회지
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• 제13권1호
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• pp.41-45
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• 1974

우리나라 씨감자에 발생하고 있는 잠복성바이러스의 종류와 이들의 감염상태를 조사하기 위하여 감자 원원종포, 원종포 그리고 원예시험장 등에서 수집한 외관상 무병 건전하게 보이는 감자와 외관상 바이러스병징이 뚜렷한 감자를 대상으로 혈청학적방법에 의해 바이러스 검정을 실시했다. 검정대상 바이러스는 Potato Virus X(PVX), Potato Virus S(PVS), Potato Virus M(PVM), 그리고 Potato Virus Y (PVY)의 4종이며, 바이러스의 검정은 van Slogteren의 미량침강법에 따라 실시했다. 결과는 다음과 같다. 1. 씨감자 생산포장에서 수집한 감자잎에서 PVX, PVS, PVM, 그리고 PVY가 검출되었는데 우리나라 감자에서 PVM이 검출되었다는 실험적 보고는 이것이 처음이다. 2. 외관상 건전하게 보이는 씨감자의 거의 $100\%$ PVX와 PVS에 약 $10\%$가 PVX+PVS+PVM에, 약 $4.5\%$가 PVX+PVS+PVY에, 그리고 $1\%$ 정도가 PVX+PVS+PVM+PVY에 각각 혼합감염되어 있었다. 3. PVX와 PVS만이 검출된 식물은 대부분 병징이 음폐되어 있었으나 PVX, PVS와 함께 PVY가 검출된 식물은 대부분 뚜렷한 병징을 나타내고 있었다. 4. 혈청학적 미량탐강법은 육안적인 관찰만으로는 검정이 어려운 PVX, PVS, PVM 및 mild strain의 PVY를 씨감자 생산지에서 대규모의 식물은 대상으로 신속정확히 검정하는데 애우 편리한 방법으로 생각된다.

• Parasites, Hosts and Diseases
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• 제58권6호
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• pp.609-617
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• 2020

Plasmodium vivax reemerged in 1993. It has been sustained for more than 25 years and become one of the important indigenous parasitic diseases in northern and western parts of the Republic of Korea near the demilitarized zone. In particular, relapse is a significant concern for the control of malaria, as short- and long-term incubation periods vary among those infected in Korea. In this study, the prevalence of asymptomatic carriers was examined among residents of high endemic areas of vivax malaria during nonseasonal transmission of mosquitoes. Blood samples from 3 endemic regions in northwestern Korea were evaluated by microscopic examination, rapid diagnostic testing, and nested PCR to identify asymptomatic patients carrying malaria parasites in the community. However, no positive malaria case among residents of endemic areas was detected. Additionally, serological analysis was carried out to measure antibodies against 3 antigenic recombinant proteins of P. vivax, merozoite surface protein 1-19, circumsporozoite surface protein-VK210, and liver-stage antigen (PvLSA-N), by the protein array method. Interestingly, seropositivity of sera between previous exposure and samples without exposure to malaria was significantly higher using the PvLSA-N antigen than the other antigens, suggesting that PvLSA-N can be used as a serological marker to analyze the degree of exposure for malaria transmission in endemic areas. This indicates a very low asymptomatic carrier prevalence during the nonmalaria season in the endemic areas of Korea.

• 대한수의학회지
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• 제62권4호
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• pp.29.1-29.7
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• 2022

Vaccination against Newcastle disease (ND) is the most effective means of controlling the disease, and these vaccines are commercialized only after their safety and effectiveness have been verified through tests that comply with Korean Standards of National Lot Release for Veterinary Biologics. This study investigated whether a relatively convenient and safe serological test can be used in place of the challenge test using highly virulent ND virus. Hemagglutination inhibition (HI) assay and enzyme-linked immunosorbent assay (ELISA) were considered positive of log₂ 2 or more and cutoff value of 200 or more, respectively, in both live and inactivated vaccines. However, when the antibody levels of the live and inactivated vaccines induced using the Ulster 2C, KBNP-C4152R2L, and K148/08 strains were compared, the antibody titers for inactivated vaccines were significantly higher than those for live vaccines in both the HI assay and ELISA. A strong positive correlation was observed between HI and ELISA antibody titers. The live vaccines corresponded to a survival rates of ≥ 80% and the inactivated vaccines corresponded to 100% survival rates. This study confirmed that standard efficacy tests can serve as serological tests, and can replace the challenge test and that the vaccine approval process can be improved.

• The Plant Pathology Journal
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• 제17권6호
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• pp.386.1-386
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• 2001

• 미생물학회지
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• 제24권2호
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• pp.175-183
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• 1986

The isolate HL-15 of Bacillus thuringiensis had common biochemical characteristics of the 23 serovarieties of B. thuringiensis. The isolates formed round endotoxin crystals which killed insect larvae, showed independent serological H antigen to the 23 serotypes, and contained two defferect DNA elements with over 100 Mdaltons of molecular weights.

• 대한수의사회지
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• 제20권7호
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• pp.436-442
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• 1984

A total of 1,395 cattle of domestic and foreign origin was tested for the presence of antibody against BVD virus by a micro-neutralization test. Of 1,295 sera collected from cattle born in Korea, $38.4\%$ had antibody to BVD virus. Korean nativ

• 대한수의사회지
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• 제9권2호
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• pp.23-34
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• 1965

In 1957, a Toxoplasma infection among swine was first discovered in Korea. Thereafter, Complement Fixation Inhibition Test was applied to 2,017 swine serum samples which were obtained from all over the country except Cheju Island. Significant results are

• 대한수의사회지
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• 제19권2호
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• pp.27-33
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• 1983

A total of 110 adult dogs (12pet dogs, 27 stray dogs, 71 other dogs collected from were examined for Brucella canis infection, and 11cases ($10\%$) were found to have Seoul areal high titered agglutinin. Especially, the positive titer (1 : 160

• 대한수의학회지
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• 제31권2호
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• pp.209-215
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• 1991

Serological survey were conducted on the leptospiral antibody in domestic animals which were fed in the three rural village occurred human leptospirosis. Names of three villages are Shinnam-li, Shinjeop-li and Jinai-li which are located in near the northeastern part of Yeoju town in Kyunggi province. Total 66 serum samples were collected from the domestic animals in which 12 dairy cows, 10 Korean native cattle, 12 pigs and 32 dogs were included. Leptospiral antibody were detected with 4 different serovars of leptospira living antigens, such as Leptospira icterohaemorrhagiae, L. pomona, L. canicola and L. tarassovi by microscopic agglutination test for each serum sample. The results are obtained as follow. 1. All 66 sera collected from the domestic animals at three villages showed negative reaction with 4 different serovars of leptospiral antigen. 2. Only one serum sample taken from a dairy cow in Shinjeop-li showed a weak positive reaction with Leptospira tarassovi. It is suggest that this positive case is not infected with L. tarassovi, but with vaccination. 3. It is indicated that all domestic animals which wen, fed in the villages occured human leptospirosis were not infected with above 4 different serovars of leptospira at least.