• International Journal of Industrial Entomology and Biomaterials
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• 제14권1호
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• pp.15-21
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• 2007

Three newly authorized bivoltine silkworm hybrids namely, $CSR2{\times}CSR4$ (productive single hybrid), $(CSR6{\times}CSR26){\times}(CSR2{\times}CSR27)$ (productive double hybrid) and $CSR18{\times}CSR19$ (robust single hybrid) were chosen for the present study. These hybrids were subjected to different temperature and humidity treatments i.e., $25{\pm}$1^{\circ}C and RH $65{\pm}5%$ (control), $30{\pm}1^{\circ}C$, with combinations of low relative humidity (RH $65{\pm}5%$) and high RH ($85{\pm}5%$) at different stages during rearing and spinning of silkworm larvae. The larvae of after 3rd moult were subjected to different thermal and humidity stress till the assessment of cocoon traits. The comparative rearing and reeling performance clearly indicated that the deleterious effect of high temperature and high RH was more pronounced for the majority of traits such as cocoon uniformity, cocoon weight, shell weight, shell percentage, reelability, filament length, raw silk percentage raw silk recovery denier and waste percentage on silk weight than other temperature and RH treatments and this effect was almost similar for all three silkworm hybrids studied. The present investigation clearly indicate that the deleterious effect of high temperature and high RH was more pronounced on rearing and spinning of silkworm larvae than other temperature and RH treatments and similar effect was noticed for all the three silkworm hybrids studied. The cocoon characters can be improved by providing ideal environmental conditions even during spinning stage of larvae affected with high temperature and RH. The study also suggest that high temperature and low humidity has greater effect during rearing stage than spinning stage.

• 한국응용곤충학회지
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• 제59권3호
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• pp.185-202
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• 2020

수원 지방에서 조명나방(Ostrinia furnacalis)(나비목: 포충나방과) 성충 발생횟수와 유충 휴면이 유도되는 시기를 분석하였다. 성충은 일년에 3회 발생 하였는데, 1화기는 5월 초부터 7월 초까지, 2화기는 7월 초중순부터 8월 초중순까지, 3화기는 8월 중순부터 10월까지이었다. 7월말부터 8월 중순 사이에 갓부화 유충을 야외에서 사육하기 시작하였을 때, 그 해와 이듬해 용화한 개체들이 같이 발생하였다. 이후 사육된 집단에서는 모두 월동 유충들만 출현하였다. 야외에서 7월과 8월 중 채집된 유충들에서는 월동하거나 월동하지 않는 개체들이 같이 발생하였고, 이후 채집된 개체들에서는 모두 월동하는 개체들만 나타났다. 이 결과들은 수원에서 조명나방은 연중 2세대와 3세대를 경과하는 개체들이 같이 발생하는 복합 생활사를 갖는 것을 보였다. 실험실에서, 조명나방 유충을 영기별로 탈피 직후(9시간 이내)에 휴면유도 조건(11:13 시간 = 명:암 광주기, 20℃)에 처음 처리하였을 때, 거의 모든 유충들에서 휴면이 유도되었다. 유사한 처리를 5령으로 탈피한 유충 나이별로 적용하였을 때, 5령 3일과 4일 나이의 유충에 대한 처리에서는 휴면유도율이 감소하였다. 한편 알에서 갓 부화했을 때부터 휴면유도 조건에서 사육하던 유충들을 3령, 4령, 5령 탈피 직후에 비휴면 조건으로 옮겼을 때, 거의 대부분의 유충들은 휴면에 유도되지 않았다. 그 결과로부터 5령 초기 나이의 유충들이 휴면유도 자극에 반응하는 최종 단계라고 추정되었다. 비휴면 유충들에 비해, 휴면이 유도된 유충들에서는 혈림프 내 트레할로스 함량이 증가하였고, 몸체 과냉각점이 낮아졌다.

• Parasites, Hosts and Diseases
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• 제34권3호
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• pp.161-168
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• 1996

중국산 수입 미꾸리로부터 획득한 악구충 유충의 형태학적 특징을 관찰하고 종 동정하고자 하였다. Early third-stage larva($EL_3$)는 중국산 미꾸리의 내장에서 분리 수집하였고 advanced third-stage larva($AdL_3$)는 $EL_3$를 마우스에 실험감염시킨 후 4주에 회수하였다 미꾸리 및 마우 스로부터 획득한 충체들을 10% formalin으로 고정하였고 alcohol-glycerin 용액을 거쳐 glycerinfelly로 봉입한 후 관찰 및 계측하였다. 총 9 493마리의 중국산 미꾸리를 조사하였던 바 총 369마리의 $EL_3$가 검출되었다. $EL_3$는 평균 0.624{\;}{\times}{\;}0.101 mm 크기이었고 체표면에 약 190 줄의 가로주름(transverse striation)이 나 있었으며 각 주름에는 미세한 가시(cuticularspine)들 이 일정한 간격으로 배열되어 있었다. 충체의 전단에는 1쌍의 구순이 돌출되어 있었고 그 뒤로 근 육성의 인두(평균 0.229 mal)와 갈색의 장이 이어졌으며 후단 근처의 복측에 항문이 개구하였다 특징적인 head bulb(평균 0.034{\;}{\times}{\;}0.071 mm)에는 소구(hooklets)가 평균 36 7개, 39.5개, 41.6개 및 44.3개씩 4줄 배열되어 있었고 head bulb 바로 뒤에는 2쌍의 cervical sac(평균 0.133 mm)이 인두를 따라 길이로 배열되어 있었다. AdLB는 평균 $2.660{\;}{\times}{\;}0.346{\;}mm$ 크기이었고 충체 전단의 구순 특징적인 head bulb(평균 $0.097{\;}{\times}{\;}0.193{\;}mm$), 근육성의 인두(평균 0.755 mm), 2쌍의 cewicalsac(평균 0.355 mm). 갈색의 장 등을 가지고 있었다 대부분의 충체 head bulb에는 소구가 평균 39.0개, 41 9개, 43.9개 및 45.6개씩 4줄 배열되어 있었으나 몇 몇 충체에서는 5번째 줄에 3~7개의 소구가 배열되어 있었다. 이상의 형태학적 특징 및 계측치를 토대로 하여 중국산 수입 미꾸리와 실험감염 마우스로부터 획득한 악구충을 돼지악구충 (Gnathostoma hispidum)의 제3기 유충으로 동정하였다.

• 수산해양교육연구
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• 제29권2호
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• pp.422-435
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• 2017

Intermolt periods, growth rates, survival (%) and relative growth of the megalopa larvae of Portunus trituberculatus (Miers, 1876) were studied up to the crab 7th stage for 160 days in the 3 different temperature groups in which each has 60 larvae. The higher the water temperature was the shorter the intermolt period was in each crab stage. In addition, a deviation of intermolt periods was shown as few as the water temperature gets higher. The intermolt period in the 7th crab stage was $29.8{\pm}3.26$ days in the experimental group at the room temperature, $45.2{\pm}3.89$ days at the temperature of $17^{\circ}C$, and $25.6{\pm}2.23$ days at the temperature of $27^{\circ}C$, respectively. The survival (%) of larvae of P. trituberculatus (the crab 7th stage) is the highest in the group at the room temperature: However, they showed 15% at the temperature of $27^{\circ}C$ and 10% at the temperature of $17^{\circ}C$. All the groups were shown the similar relative growth, but significant differences appeared in some comparison. The sizes (mean growth of carapace width) of the crabs in the group at the temperature of $27^{\circ}C$ reached 5.01~25.45 mm length (it is the longest among the groups) from the crab 1th to the crab 7th stage. However, the sizes (mean growth of carapace width) of room temperature were 4.99~22.26 mm and the size of crab in the group at the temperature of $17^{\circ}C$ reached 4.8~17.26 mm, The sizes (mean growth of carapace length) of the crabs in the group at temperature of $27^{\circ}C$ reached 2.88~13.56 mm, However, the size of the crab in the group at the room temperature showed 2.88~12.34 mm, while in the group at temperature of $17^{\circ}C$, their average growth of carapace length were 2.51~8.03 mm. The growth rates of larvae of P. trituberculatus (from the crab 1th to the crab 7th stage) were changed with the increase of the instar stage, however their changes showed irregular.

• International Journal of Industrial Entomology and Biomaterials
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• 제37권2호
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• pp.100-104
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• 2018

The rearing of black soldier flies in Korea is affected by seasonal factors such as temperature and sun light; for this reason, it requires a great deal of effort to rear and maintain black soldier flies during the winter. In this study, we investigated how starvation affects larval development. After hatching the larvae, they were fed for 5 or 10 d and then starved for a certain period to see how they recovered. The length and width of larvae were estimated to be 18.18 to 21.96 mm, 5.19 to 6.04 mm, respectively. Larvae survivorship to the pupal stage was significantly different between groups and periods of starvation. The groups of fed for 5 d then starved showed a high survival rate until 20 d starvation and then the survival of larvae rapidly decreased. The survival rate of the larvae was abruptly decreased for 20 d starvation in the groups of fed for 10 d and starved, and then gradually decreased until 60 d starvation thereafter. Our research attempted to influence larvae development through starvation and provides basic information on how to culture the black soldier fly effectively and economically throughout the year.

• 한국양식학회지
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• 제11권3호
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• pp.337-344
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• 1998

경북 영덕군 축사면 근해 수심 약 200m해역에서 채포된 대게, Chionoecetes opilio 어미를 실내 수조에서 사육, 산란시켜 외포란된 알을 연속적으로 채취하여, 그 외부 형태에 의한 발생 단계를 구분하고, 부화한 유생의 형태적 특징을 조사하였다. 사육 수온은 약 5 degree C 정도 였으며, 부화까지 총 소요일수는 276~331일 이었다. 그 결과를 요약하면 다음과 같다. 1. 난 발생 단계 제 1기 난할 및 포배기 (수정에서 원구 출현까지, 24일) 제 2기 낭배기 (U자상 외배엽의 출현전까지, 72일) 제 3기 naupliua기 (악각 원기 출현전 까지, 22일) 제 4기 metanauplius기 (복안에 색소형성전까지, 57일) 제 5기 복안 색소 형성기 (30일) 제 6기 악각 색소포 형성기 (56일) 제 7시 부화 전기 (36일) 2. 부화 유생의 형태적 특징 모든 부화 유생은 prezoea상태로 부화했으며 30문 ~1시간후 zoea I기로 변태했다. zoea I기 유생 두흉부의 크기는, rostral spine 끝에서 dorsal spone 끝까지 길이가 4.6~5.1 양측면 lateral spine의 폭은 3.2~3.5mm였다. 또 몸통은 5개의 분절과 끝이 2갈래로 나누어진 미절로 나누어져 있다.

• Parasites, Hosts and Diseases
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• 제41권2호
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• pp.97-100
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• 2003

Acute gastric anisakiasis with multiple anisakid larvae infection is reported. A 68-year-old woman residing in Busan, Korea, had epigastric pain with severe vomiting about 5 hours after eating raw anchovies. Four nematode larvae penetrating the gastric mucosae in the great curvature of the middle body and fundus were found and removed during gasteroendoscopic examination. Another one thread-like moving larva was found in the great curvature of upper body on the following day. On the basis of their morphology, the worms were identified as the 3rd stage larvae of Anisakis simplex. This case is acute gastric anisakiasis provoking severe clinical problems by the multiple infection and the greatest number of anisakid larvae found in a patient in Korea.

• Parasites, Hosts and Diseases
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• 제43권2호
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• pp.51-55
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• 2005

The autoinfective filariform larva of Strongyloides stercoralis causes hyperinfection in immunosuppressed hosts. Here we report on the case of a male patient who was admitted to the emergency room at Gwangju Veterans Hospital with a complaint of dyspnea, and who was receiving corticosteroid therapy for asthma. Many slender larvae of S. stercoralis with a notched tail were detected in Papanicolaou stained sputum. They measured $269\pm21.2{\mu}m$ in length and $11\pm0.6{\mu}m$ in width. The esophagus extended nearly half of the body length. The larvae were identified putatively as autoinfective third-stage filariform larvae, and their presence was fatal. The autoinfective filariform larva of S. stercoralis has not been previously reported in Korea.

• The Korean Journal of Ecology
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• 제15권3호
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• pp.257-265
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• 1992

The effects of insecticide dimilin including the technical grade(tg) and wettable power(wp-25), inhibiting the synthesis of chitin in the cuticle of insect larvae, and herbicides alachlor and atrazine on the development of shrimp caridina denticulata denticulata were investigated in various concentrations. This species is abundant in the freshwater such as river and pond. The shrimp larvae were reared at dimilin solutions(tg and wp 2), alachlor solutions, and atrazin solutions. the concentrations of dimiline were 0, 1, 5, 10 and 25 ppb dimilin solutions, and those of alachlor and atrazin were 0, 1, 5, 10 and 25ppm, respectively.mortality was high at 10 ppb when the larvae were exposed to dimilin and at 25ppm in the case of alachlor and atranzine solutions. If lethal concentration is defined as a concentration in which less than 10% of larvae to the post larval stage from hatching it can be concluded that the lethal concentration of dimilin is 5ppb, and that of alachlor and atrazin is 25 ppm.

• Parasites, Hosts and Diseases
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• 제49권1호
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• pp.39-44
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• 2011

The infection status of marine fish and cephalopods with Anisakis simplex third stage larva (L3) was studied over a period of 1 year. A total of 2,537 specimens, which consisted of 40 species of fish and 3 species of cephalopods, were purchased from the Cooperative Fish Market in Busan, Korea, from August 2006 to July 2007. They were examined for A. simplex L3 from the whole body cavity, viscera, and muscles. A. simplex L3 were confirmed by light microscopy. The overall infection rate reached 34.3%, and average 17.1 larvae were parasitized per infected fish. Fish that recorded the highest infection rate was Lophiomus setigerus (100%), followed by Liparis tessellates (90%), Pleurogrammus azonus (90%), and Scomber japonicus (88.7%). The intensity of infection was the highest in Gadus macrocephalus (117.7 larvae per fish), followed by S. japonicus (103.9 larvae) and L. setigerus (54.2 larvae). Although abundance of A. simplex L3 was not seasonal in most of the fish species, 10 of the 16 selected species showed the highest abundance in February and April. A positive correlation between the intensity of L3 infection and the fish length was obvious in S. japonicus and G. macrocephalus. It was likely that A. simplex L3 are more frequently infected during the spring season in some species of fish. Our study revealed that eating raw or undercooked fish or cephalopods could still be a source of human infection with A. simplex L3 in Korea.