• Mycobiology
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• 제42권4호
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• pp.385-390
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• 2014

The beet armyworm Spodoptera exigua (Lepidoptera: Noctuidae) is difficult to control using chemical insecticides because of the development of insecticide resistance. Several pest control agents are used to control the beet armyworm. Entomopathogenic fungi are one of the candidates for eco-friendly pest control instead of chemical control agents. In this study, among various entomopathogenic fungal strains isolated from soil two isolates were selected as high virulence pathogens against larva of beet armyworm. Control efficacy of fungal conidia was influenced by conidia concentration, temperature, and relative humidity (RH). The isolates Metarhizium anisopliae FT83 showed 100% cumulative mortality against second instar larvae of S. exigua 3 days after treatment at $1{\times}10^7$ conidia/mL and Paecilomyces fumosoroseus FG340 caused 100% mortality 6 days after treatment at $1{\times}10^4$ conidia/mL. Both M. anisopliae FT83 and P. fumosoroseus FG340 effectively controlled the moth at $20{\sim}30^{\circ}C$. M. anisopliae FT83 was significantly affected mortality by RH: mortality was 86.7% at 85% RH and 13.4% at 45% RH. P. fumosoroseus FG340 showed high mortality as 90% at 45% RH and 100% at 75% RH 6 days after conidia treatments. These results suggest that P. fumosoroseus FG340 and M. anisopliae FT83 have high potential to develop as a biocontrol agent against the beet armyworm.

• 보건행정학회지
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• 제18권4호
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• pp.49-65
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• 2008

The single-item question of self-assessed health status has consistently been reported to be associated with mortality in some developed countries, even after controlling for a wide range of health measurements and known risk factors for. mortality. It was intended in this study to find out whether or not such a relationship would also be valid in Korea. This study examined the effect of point of reference year on. the, predictive validity of self-assessed health for mortality in 6-year follow-up period. we need to test the validity of the self-assessed health, as an indicator for assessing health status using Cox's proportional hazard model. For the analysis, we used the data from the 2nd (1999) to the 7th survey of "Korean Labor and Income Panel Study," and assessed relative risk of death based on subjective health state by tracing 11,366 people who replied to the question of self-assessed health state in the 2nd year. According to the result, those who reported poor self assessed health state in the 2nd year showed a relatively high death rate, and their relative risk of death was significantly higher. Such a relationship was accentuated if the predictive value of the 2nd survey result would be replaced by the average of the cumulative data on the past six years. Thus, it can be concluded that self-assessed health state is valid as an index for assessing Korean people's health status.

• 생명과학회지
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• 제17권10호
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• pp.1434-1440
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• 2007

본 연구는 넙치의 면역반응에서 버섯균사체 (상황버섯, 운지버섯) 혼합배양추출물의 효과에 대해서 연구하였다. 혼합배양추출물은 넙치에 대해서 성장, 혈액, 라이소자임활성, 백혈구, 식세포활성 및 Vibrio anguillarum에 대한 질병저항성에 관해서 평가되었다. 성장에 있어서 버섯균사체 혼합 배양 추출물을 섭이한 그룹의 체중은 52 g 전장은 2.1 cm가 대조구보다도 증가하였다. 혈액학적으로 버섯균사체 혼합 배양추출물을 경구투여 했을 때 글루코오스의 양이 증가하였다. 그러나 각 그룹에 대한 COT (glutamic oxaloacetic transaminase), GPT (glutamlc pyruvic transamlnase), TG, TP, LDH (lactate dehydronase)의 유의적인 차이는 없었다. 라이소자임 활성은 대조구 보다 실험구에서 80%의 높은 결과를 얻을 수 있었으며, 식세포 활성은 실험구에서 대조구 보다 60% 높은 활성을 보였다. 라이소자임 활성과 식세포 활성의 결과 경우에는 12주후에 다소 감소하는 양상을 보였지만, 대조구 보다는 높은 활성을 보였다. 그리고 $7{\times}10^8\;CFU$ 농도로 어류 병원성 세균인 Vibrio anguillarum를 어류 당 투여하여 병원성 테스트를 한 결과 누적 폐사율을 대조구와 비교해 보았을 때 25%의 높은 생존율을 보였다.

• 한국환경농학회지
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• 제35권4호
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• pp.241-246
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• 2016

BACKGROUND: Recently, the widespread distribution of pesticides in the hive has been of concern about pesticide exposure on honeybee (Apis mellifera L.) health. Larval toxicity was adapted to assess the synergistic and antagonistic interaction of cumulative mortality to the honeybee larvae of the four most common pesticides detected in pollen. METHODS AND RESULTS: Acetamiprid($3.0{\mu}l/L$), chlorothalonil ($803.0{\mu}l/L$), coumaphos ($128.0{\mu}l/L$), and tau-fluvalinate ($123.0{\mu}l/L$) were tested in combination; binary, ternary and four component mixture. Larvae were exposed to four pesticides mixed in diet at the average levels detected in pollen. As a result, synthetic toxicity was observed in the binary mixture of acetamiprid with coumaphos. The binary and ternary component mixtures of tested pesticides have mostly demonstrated additive effect in larval bees. The significant antagonistic effects were found in four parings of mixtures including chlorothalonil added to acetamiprid/tau-fluvalinate or acetamiprid/coumaphos/tau-fluvalinate, and tau-fluvalinate added to acetamiprid/chlorothalonil or acetamiprid/coumaphos/chlorothalonil. CONCLUSION: Interactions between combinations of four pesticides showed mostly additive or antagonistic effects in larval bees. Therefore, predicting the larval mortality of pesticides mixtures on the basis of the results of single pesticide may actually overestimate the risk. We suggest that pesticide mixture in pollen be evaluated by adding their toxicity together for complete data on interactions.

• 한국수산과학회지
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• 제53권4호
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• pp.628-636
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• 2020

Streptococcosis in the olive flounder Paralichthys olivaceus can be caused by Streptococcus parauberis. We compared three routes of administration for experimental injections of the S. parauberis 19FBSPa0003 strain in the olive flounder. Pathological changes were observed during the experimental infection. Inflammation of the serous membrane in the liver, intestine, spleen and heart was the major pathological change found in the infected olive flounder. No mortality was observed in fish that received intraperitoneal (IP) injection at less than 1×10⁴ colony-forming unit (CFU)/fish. The lethal dose 50 for olive flounder, given an intravenous (IV) injection, was 7.94×10⁴ CFU/fish. Fish with a higher concentration of IV injected S. parauberis (1×10⁸ CFU/fish) died within a maximum of two days. However, serious necrosis and bacterial proliferation in ellipsoidal cells of the spleen and heart tissues were found in moribund or dead fish, 1-2 days after IV injection. Similar histopathological signs were observed in olive flounder inoculated by subcutaneous (SC) infected and naturally infected. In addition, SC was also strongly associated with bacteria concentration and cumulative mortality rate. Based on these results, SC is the recommended method for artificial infection by S. parauberis in the olive flounder.

• 대한수의학회지
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• 제34권3호
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• pp.627-633
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• 1994

A study on efficacy and safety of Bio-Gammamix was performed to use for the preventive drug against bacterial diseases to mirror carp(Cyprinus carpio), rainbow trout(Salmo gairdneri), eel(Anguilla japonica) and flounder(Paralichthys olivaceus). The main ingredients of Bio-Gammamix were ferrous fumarate and mixed extrated powders of licorice root, ox bile and garlic. The test drug was proved to improve feeding habit and feed efficiency and decrease cumulative mortality remarkably. After administration, no side effects and histopathological changes were observed. We can prevent outbreaks of bacterial diseases of fish by the dosage of 1kg/ton of fish body weight perorally once or two times in a day for 7 days and Bio-Gammamix is thought to be used effectively an widely against most bacterial fish pathogens.

• 한국농공학회논문집
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• 제60권2호
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• pp.75-84
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• 2018

Thermal stress of livestock has been issued due to recent climate change trends and this causes reproductive disorders, decreased feed consumption, immunosuppression, and increased mortality of animals. Concept of THI has been widely used to quantitatively evaluate the degree of thermal stress for animals, however use of this concept is restricted for animals living in the enclosed facilities such as mechanically ventilated broiler houses. In this study, time-based internal energy flow and variation trends of temperature and humidity were analyzed based on BES technique. Local weather data, insulation characteristics of building materials, heat and moisture generation rate from broilers according to age, algorithm of ventilation operation were adopted for boundary condition of the model to accurately compute THI values inside the mechanically ventilated broiler house. From the BES computation, excess frequency of THI threshold in Jeju city was highest on the assumption that air conditioning equipments were not installed. When general raising density ($39kg\;m^{-2}$) was adopted, total 2,191 hours were exceeded. Excess hours of THI threshold were strongly related to the cumulative air temperature ($R^2=0.87$).

• 한국어병학회지
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• 제12권2호
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• pp.73-81
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• 1999

본 연구에서는 구기자의 투여가 나일틸라피아의 면역 반응에 미치는 영향을 알기 위하여, 나일틸라피아에 구기자 3% 첨가 사료를 14주일간 투여하면서 어병 세균인 Edwardsiella tarda 유래의 FKC와 ECP를 복강 주사 또는 침지법으로 FKC와 ECP를 단독 또는 혼합 처리하였을 때의 비특이적 및 특이적 면역 반응에 대하여 조사하였다. 비특이적 면역 반응의 지표로서 보체의 용혈능과 lysozyme의 활성을, 특이적 면역 반응의 지표로서 로젯 형성 세포 수의 변화와 응집 항체가를 조사하었으며, 어병 세균인 E. tanla로 생균 공격 실험하여 상대 생존률을 구하였다. 구기자 첨가 사료를 투여하였을 때, 조사한 모든 비특이적 면역 반응 지표들이 활성화되었으며, 백신 처리 후에도 무첨가 사료 투여구에 비하여 높은 면역 활성을 보였다. 백신 처리구의 응집 항체가는 FKC와 ECP의 혼합 처리구가 가장 높았고 FKC 주사구, FKC 침지구의 순으로 응집 항체가가 낫게 나타났으며, 로젯 형성 세포 수도 같은 경향을 보였다. E. tarda로 생균 공격 실험한 결과, 구기자 투여만으로도 방어력이 증가되었다. 그리고 백신 처리하였을 때에는 혼합 처리구가 가장 높은 방어력을 보였으므로, 본 실험에서 사용한 구기라는 기존의 adjuvant와 같이 면역 반응의 증강 효과가 있는 것으로 판단되며, FKC와 ECP로 혼합 백신 처리하는 방법은 효과가 기대되는 백신 방법으로 사료된다.