• 한국응용곤충학회지
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• 제45권3호
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• pp.333-337
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• 2006

담배거세미나방에(Spodoptera litura)에 의한 콩의 피해해석을 하고자 콩 생육기 및 담배거세미나방 유충 밀도를 달리하여 조사한 결과 콩 생육시기별 유충 밀도에 따른 수량감소율과의 관계식은 개화기에는 (1) Y = 1.655X - 6.025 ($R^{2}=0.952$), 착협기에는 (2) Y = 0.725X - 0.475 ($R^{2}=0.986$), 립비대기에는 (3) Y = 0.635X - 1.325 ($R^{2}=0.986$)였다. 이 관계식을 근거로 하여 콩 생육시기별 피해허용수준(수량감소 5% 기준)을 산출한 결과, 주당 2-3령 유충의 밀도는 개화기6.7 마리, 착협기 7.5마리, 립비대기는 10.0마리였다. $28^{\circ}C$에서 1령, 2령, 3령, 4령, 5령 및 6령 유충의 1일 섭식량은 0.3, 0.7, 2.6, 4.0, 20.1 및 $55.8\;cm^{2}$ 이었다.

• Fisheries and Aquatic Sciences
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• 제2권1호
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• pp.78-84
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• 1999

Ultrastructural changes in the cuticle of Paleamon serrifer associated with the intermolt cycle were examined and quantified as changes in the cuticular thickness. The cuticular thickness in each zoea stage increased with time elapsed after molting. The cuticle in the premolt stage was about 1.5 and 3 times thicker than that in the postmolt and intermolt stage, respectively. The cuticle in the premolt stage, including the molting space, was more than 5 times as thick as in the postmolt stage. In addition, newly hatched larvae were individually reared in the laboratory and body length for each specimen was measured frequently until the end of zoea VI. An average increase in body length between one zoea stage and the next is about $10\%$ of the length of the previous stage. Within individual zoea stages, the premolt stage had a body length some 0.3% longer than that of the postmolt stage, indicating a growth rate of about 0.03 mm/d.

• 한국잠사곤충학회지
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• 제29권2호
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• pp.38-43
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• 1987

카드미움을 누에에 투여하여 발육경과에 따른 암수간의 누에 혈액단백질의 변화 및 GOT, GPT활성을 조사하였다. 얻어진 결과를 요약하면 다음과 같다. 1. 카드미움처리구는 무처리구에 비해 총혈액단백질 함량이 낮았다. 한편 카드미움처리에 의한 암수간의 총단백질함량의 변화에 있어서는 숫컷이 더 큰 영향을 받고 있어Te. 2. 발율경과에 따른 Albumin함량은 암컷에 있어서는 카드미움의 영향이 적은데 반해 수컷에 있어서는 무처리에 비해 약 7% 감소하였다. 그러나. Globulin은 암컷 숫컷 모드 카드미움의 영향이 컸다. 3. GPT 및 GOT의 활성은 카드미움에 의해 다같이 저해되었다.

• Fisheries and Aquatic Sciences
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• 제19권4호
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• pp.20.1-20.12
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• 2016

The osteological development in Sebastes koreanus is described and illustrated on the basis of 32 larvae [6.11-11.10 mm body length (BL)] and a single juvenile (18.60 mm BL) collected from the Yellow Sea. The first-ossified skeletal elements, which are related to feeding, swimming, and respiration, appear in larvae of 6.27 mm BL; these include the jaw bones, palatine, opercular, hyoid arch, and pectoral girdle. All skeletal elements are fully ossified in the juvenile observed in the study. Ossification of the neurocranium started in the frontal, pterotic, and parietal regions at 6.27 mm BL, and then in the parasphenoid and basioccipital regions at 8.17 mm BL. The vertebrae had started to ossify at ~7.17 mm BL, and their ossification was nearly complete at 11.10 mm BL. In the juvenile, although ossification of the pectoral girdle was fully complete, the fusion of the scapula and uppermost radial had not yet occurred. Thus, the scapula and uppermost radial fuse during or after the juvenile stage. The five hypurals in the caudal skeleton were also fused to form three hypural elements. The osteological results are discussed from a functional viewpoint and in terms of the comparative osteological development in related species.

• 한국수산과학회지
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• 제46권6호
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• pp.801-806
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• 2013

Spiny lebbeid shrimp Lebbeus groenlandicus larvae were reared in the laboratory to estimate the energy budget from the zoeal to the post-larval stage. Energy expended by larvae on growth and respiration was determined from values for feeding, growth, molting, and metabolism. We calculated that 16.22 J were used for growth throughout all larval stages. Energy loss during molting was estimated as 1.03 J, and energy used for respiration was estimated as 1.31 J. Energy taken in by feeding was estimated as 77.16 J, while the sum of energies expended in excretion and egestion was 58.61 J. Larvae were estimated to assimilate 24.6% of ingested food as energy and to use ~85% of the assimilated energy for somatic growth. Gross growth efficiency ($K_1$) and net growth efficiency ($K_2$) were shown to be ~22% and 93%, respectively. Maintenance costs of respiration were estimated as ~9.7% of assimilated energy.

• 한국수산과학회지
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• 제39권2호
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• pp.94-99
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• 2006

The tadpole larvae of most ascidians have two sensory pigment cells in their brain vesicle. The anterior otolith pigment cell is sensitive to gravity, whereas the posterior ocellus pigment cell responds to light. Besides these two sensory cells, the larvae also possess another type of sensory receptor cell: hydrostatic pressure receptor (Hpr) cells. The Hpr cells have been presumed to sense hydrostatic water pressure, although no functional analysis has been performed. In larvae of the ascidian Halocynthia reretzi, the development of the Hpr cells and their structure in the brain vesicle are poorly understood. To investigate the morphology and formation of the Hpr cells, we established a monoclonal antibody, Hpr-1, that specifically recognizes Hpr cells. The Hpr-1 antigens became detectable in the brain vesicle at the late tailbud stage. Each Hpr cell projected a small globular body, connected by a short stalk, into the lumen of the brain vesicle. The brain vesicle showed remarkable left-right asymmetry. Pigment cells were located on the right side in the lumen of the brain vesicle, whereas Hpr cells were present in the left side. After metamorphosis, the Hpr cells were observed near the rudimental siphons of the juvenile.

• 한국발생생물학회지:발생과생식
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• 제19권4호
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• pp.189-196
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• 2015

This study was examined the ovogenesis of Ussurian bullhead, Leiocassis ussuriensis and the morphological development of its larvae and juveniles and to use the results as basic information for the preservation of species and resource enhancement. For artificial egg collection, human chorionic gonadotropin (HCG) was injected at a rate of 10 IU per gram of fish weight. During breeding period, water temperature maintained at $24.5{\sim}26.5^{\circ}C$ (mean $25.0{\pm}0.05^{\circ}C$). The process of ovogenesis reached the two-cell stage in 50 minutes after fertilization. In 73 hours of fertilization the movement of the embryoid body became active state and the larvae began to hatch from the tail through the oolemma. Length of prelarvae were 6.33~6.50 mm long (mean $6.40{\pm}0.06mm$) just after hatching having yolk with their mouth not opened. After thirty eight days of hatching, juveniles were 30.6~32.5 mm long (mean $31.5{\pm}0.65mm$). The color was dark yellowish brown throughout the entire body, and the number of caudal fin rays developed to thirty six perfectly.

• 한국어병학회지
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• 제21권3호
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• pp.167-174
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• 2008

Few studies on parasitic scutica-like ciliates (SLCs) influencing larval growth and survival during the seed production of the Japanese scallop, Patinopecten yessoensis have been performed in spite of relatively high magnitude of their infectious damage to the larvae. In the mass seed production of the scallop, SLCs were never infectious during D-larval stage which lasted 6 to 7 days. Indeed, the infection first occurred in 2 to 4 days after first umbo-staged larvae. A regular selection of active larvae in swimming behavior kept larval SLC infection low throughout the culture compared to unselected control (P<0.05) in which all the larvae alive were contained. Higher infection frequencies of the unselected control resulted in lower larval survivals and wider range of larval size distribution that drove larval attachment rate lower. To the worse, the nursery spats from the higher SLC infection exhibited a retarded growth and elevated occurrence of abnormal scallop.

• International Journal of Industrial Entomology and Biomaterials
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• 제19권2호
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• pp.221-228
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• 2009

Nosema sp. infection in the Indian tasar silkworm, Antheraea mylitta exerts a complex of influences on its host. The instar duration was extended significantly (P<0.001) except in $1^{st}$ instar. The infected larvae took about 48 days to reach the spinning stage against 40 days in the uninfected ones. The final weight attained by the larva at the end of each instar of development declined significantly following infection, as did weight gain and relative growth rate (RGR). The growth recorded/ day declined in infected larvae compared to uninfected ones from 8.2% during $1^{st}$ instar to 43.3% during $5^{th}$ instar. Food ingestion and digestion increased with advancement of the instar significantly irrespective of the status of the larvae but the relative consumption rate (RCR) declined. These parameters significantly declined in infected larvae (except food digested during $2^{nd}$ instar). The decline was more during $3^{rd}$ instar. In contrast, the approximate digestibility (AD %) was significantly higher in infected larvae than uninfected ones leaving the $1^{st}$ instar larvae unaffected. The efficiency of conversion of ingested food (ECI) and efficiency of conversion of digested food (ECD) did not change in a patterned way following the microsporidia (Nosema sp.) infection. The values of ECI significantly changed during $2^{nd}$, $3^{rd}$ and $5^{th}$ instars; while the change in ECD during $2^{nd}$, $4^{th}$ and $5^{th}$ were significant. During the entire larval life all the parameters tends to decline significantly following microsporidia infection but AD registered a significant increase. Nosema sp. spore concentration has increased 270.7 times during larval development in the course of experimentation.

• 한국발생생물학회지:발생과생식
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• 제11권2호
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• pp.79-84
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• 2007

냉동보존이 진주조개(Pincata fucata martensii) 유생의 형태 및 구조에 미치는 영향을 알아보기 위하여 냉동전후 D형 및 각정기 유생을 광학 및 전자현미경으로 조사하였다. 동해방지제는 0.2 M sucrose를 첨가한 2.0 M $Me_2SO$를 사용하였다. 냉동후 유생은 일부 패각이 손상되긴 했지만 hinge와 prodissoconch가 뚜렷하게 나타났으며, 소포체, 지질 과립, 미토콘드리아, 핵 등을 포함한 세포내 소기관들이 고르게 분포되어 있었다. 또한, 섬모가 규칙적으로 배열되어 있었고, 섬모 아래 미토콘드리아와 지질과립이 위치해 있는 것이 관찰되었으나, 일부 해동된 유생에서 섬모의 불규칙적인 배열과 섬모환이 둥글게 뭉쳐져 있는 모습이 관찰되었다. 이러한 결과는 진주조개의 D형 유생과 각정기 유생이 냉동에 쉽게 영향을 받을 수 있다는 것을 보여준다. 따라서 냉동보존 시 세포의 손상을 감소시킬 수 있는 연구가 이루어져야 할 것으로 사료된다.