• 한국동물학회지
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• 제33권2호
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• pp.200-216
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• 1990

실험실에서 사육된 눈콩게의 전 유생발생단계를 기술, 도시하였다. 눈콩게는 5 zoea(가끔 6 zoea)와 1 megalopa유생기를 가졌다. 수온 $25^{\circ}C$에서, megalopa와 제1기 carb 부화후 각각 24일과 38일만에 나타났으나 extra zoea유생기를 갖는 경우에는 31일과 48일만에 나타났다. 눈콩게의 zoea유생 거치상의 갑각가시와 배측에 하나, 복측에 두 개의 작은 가시가 있는 미절에 의하여 엽낭계속의 타종과 구분되며, megalopa 유생은 갑각의 특징에 의하여 구분될 수 있다. 그 밖의 미세한 형태적 특징들이 앞서 보고된 엽낭개속의 유생들과 비교되어 차이점이 간단히 논의되었다.

• 한국패류학회지
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• 제28권2호
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• pp.145-156
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• 2012

이 연구에서는 바지락 (Ruditapes philippinarum) 의 번식량 및 유생발생을 관찰하였으며, 이를 위하여 수정란 및 유생을 21일 간 실내사육수조를 이용하여 배양하였다. 바지락은 2011년 8월 제주시 김녕에서 채집 실험 수조로 옮겨졌으며, 다음날 자연적인 방란 방정이 관측되었다. 바지락 수정란은 19시간의 배 발생과정을 거쳐 21일 후 포복피면자유생(pediveliger) 으로 발달하였다. 조직학적 방법을 이용하여 바지락의 생식소를 관찰한 결과, 방란, 방정 전 모든 개체는 성적으로 완숙한 상태였고, 산란 후 모든 개체에서 부분산란이 관찰되었다. 효소면역학적 방법 (ELISA) 에 의한 번식량 측정 결과, 암컷 바지락의 생식소 지수는 (GSI) 산란 전 28.6%에서 산란 후 17.3%로 11.3% 감소하였으며, 추정된 포란수는 6,998,658 eggs였다. 이 연구서 광학현미경 및 전자현미경을 이용하여 관찰된 바지락 유생 발달 및 번식량은 향후 바지락 인공종묘 산업 및 바지락 자원관리에 있어 중요한 자료로 활용될 것으로 사료된다.

• 한국패류학회지
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• 제19권1호
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• pp.33-40
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• 2003

To obtain the basic information on culture conditions for the larvae of Saxidomus purpuratus, experiments were conducted on the population from southern coast for (1) the success in fertilization and development from artificial fertilization among different months of a year, (2) the viability of sperms after exposure to seawater, (3) and the effects of temperature, salinity, and food organism on the survival and growth of larvae. Gametes obtained from dissection showed high rate of fertilization at all months. But the rate of development was higher only May-July. Developmental success seemed to be related with the quality of eggs at the time of fertilization. Developmental times for 2-cell, 4-cell, 8-cell, blastula, trochophore larva, and veliger larva at 20$^{\circ}C$ were 1.5, 2, 4, 18, 24, and 32 hr, respectively. Sperms could survive for more than 8 hr, however, actively swimming sperms could be found within 1 hr after exposure to seawater. It is recommended that sperms should be used for fertilization as soon as possible when they are exposed to seawater. At temperature of 35$^{\circ}C$, all the larvae died during 48 hr. Larval survival decreased when salinity was either lower than 20 psu or higher than 40 psu, and was 0% when salinity was 10 psu. Optimal range of temperature and salinity for rearing larvae of S. purpuratus were 20-25$^{\circ}C$ and 20-40 psu, respectively. Larvae grew from 111.5 to 235.3 ${\mu}$m during 21 days. Larvae fed mixed diets grew faster than unialgal diets. The fastest growth was observed when larvae were fed on the mixture of Isochrysis galbana and Nannochloris oculata.

• International Journal of Industrial Entomology and Biomaterials
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• 제33권2호
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• pp.50-53
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• 2016

The size of head capsule is one of the most important factors for identifying developmental stage. In order to understand the developmental characteristics of the butterfly Atrophaneura alcinous, we examined fluctuations in larval head capsule size under three different temperature conditions (20, 25, and $30^{\circ}C$) and 60% humidity. As a result, larvae developed to the fifth instar at all three temperatures. The head capsule size of larvae tended to be larger at the lowest temperature and smaller at the highest temperature. The development rate showed a regular change, consistent with Dyar's rule regarding head capsule size development. Furthermore, the development of head capsule size was found to correspond to a second degree polynomial regression better than to a linear regression. On the basis of these results, it would appear to be possible to perform an accurate assessment of instar status during the development of A. alcinous.

• Molecules and Cells
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• 제38권3호
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• pp.236-242
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• 2015

Intake of caffeine during pregnancy can cause retardation of fetal development. Although the significant influence of caffeine on animal development is widely recognized, much remains unknown about its mode of action because of its pleiotropic effects on living organisms. In the present study, by using Caenorhabditis elegans as a model organism, the effects of caffeine on development were examined. Brood size, embryonic lethality, and percent larval development were investigated, and caffeine was found to inhibit the development of C. elegans at most of the stages in a dosage-dependent fashion. Upon treatment with 30 mM caffeine, the majority ($86.1{\pm}3.4%$) of the L1 larvae were irreversibly arrested without further development. In contrast, many of the late-stage larvae survived and grew to adults when exposed to the same 30 mM caffeine. These results suggest that early-stage larvae are more susceptible to caffeine than later-stage larvae. To understand the metabolic responses to caffeine treatment, the levels of expression of cytochrome P450 (cyp) genes were examined with or without caffeine treatment using comparative microarray, and it was found that the expression of 24 cyp genes was increased by more than 2-fold (p < 0.05). Among them, induction of the cyp-35A gene family was the most prominent. Interestingly, depletion of the cyp-35A family genes one-by-one or in combination through RNA interference resulted in partial rescue from early larval developmental arrest caused by caffeine treatment, suggesting that the high-level induction of cyp-35A family genes can be fatal to the development of early-stage larvae.

• International Journal of Industrial Entomology and Biomaterials
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• 제29권2호
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• pp.153-161
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• 2014

The aim of this study is to investigate the effects of ambient thermal environments on the development of swallowtail butterflies (Sericinus montela Gray). Developmental durations and survival rates of S. montela were examined at two crucial developmental stages, embryonic and larval development, at varying temperatures ranging from $15^{\circ}C$ to $35^{\circ}C$. As expected, our results indicated that increasing temperatures decreased the developmental duration and survival rate of the eggs. However, the larvae and pupae showed maximum survival rates at $20.0^{\circ}C$ and $25.0^{\circ}C$, and the represented durations were similar to those of the eggs. Larval development was stage-specific, revealing that the fourth and fifth instars at the later stages were more susceptible to temperature variation. When considering both parameters, the optimal development of S. montela occurred within the temperature range of $20.0-25.0^{\circ}C$. The lower threshold for the complete development of S. montela from eggs to eclosion of adults was calculated at $10.6^{\circ}C$ by linear regression analysis. The estimated value is similar to that of other endemic insects distributed in temperate climate zones, which indicates that S. montela belongs to a small group of swallowtails adjusted to low ambient temperatures. From the results, we predict that the full development of S. montela could be achieved within the temperature range of $17.5-30.0^{\circ}C$. Embryonic development ceased at both test temperature extremes, and no further larval development proceeded after the third instar at $35.0^{\circ}C$. These results suggest that embryogenesis can be significantly influenced by slight variations in the ambient thermal environment that fall below the optimal range.

• Animal Systematics, Evolution and Diversity
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• 제9권2호
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• pp.69-86
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• 1993

무늬발개의 유생을 수온 $25^{\circ}C$, 염분농도 33.3$\textperthousand$의 해수에서 사육하고, 전체 유생기의 형태적인 특징을 상세히 기술 및 도시하였다. 본 종은 5 zoea와 1 megalopa 유생기를 가지며, 부화시부터 megalopa와 제1기 crab까지는 각각 18일과 31일이 걸렸다. 무늬발개 제 1 zoea 유생은 갑측극이 있고, 미절과 제2촉각의 형태가 각각 B형이며, 제1소악과 제2소악의 내지가 각각 1+5, 2+2의 강모를 가지는 점은 이미 보고된 풀게속의 다른 유생들의 특징과 일치하고 있다. 풀게속의 유생 상호간의 구별될 수 있는 형태적인 특징들, 특히 측엽을 가지는 복부마디의수, 구기 부속지들의 강모식에 대하여 토의하였다.

• 한국응용곤충학회지
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• 제31권4호
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• pp.371-378
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• 1992

검정금파리의 변태에 따른 엑디스테로이드를 Radioimmunoassay법으로 측정하고, 난세포성숙에 미치는 엑디스테로이드의 효과를 조사하여 얻을 결과는 다음과 같다. 산락직후 존재하였던 난내 엑디스테로이드는 발생과정 중 감소하다가 부화 직전 다시 증가하였으며, 유충기와 용기의 성장 변태시 엑디스테로이드함량의 변화를 보면 유충-유충과 유충-용으로의 탈피시에 일시적인 증가현상을 나타냈다. 특히 용화 후 48시간에 높은 엑디스테로이드의 농도를 보였는데 이는 큐티클분비와 경화작용과 밀접한 관계가 있는 것으로 생각된다. 성충기에서는 수컷의 경우 엑디스테로이드가 거의 검출 되지 않은 반면, 암컷에서는 단백질원 섭식 후 96시간에 최고의 함량을 나타내어 난성숙도와 일치하는 변화를 보였다. 엑디스테로이드 처리와 난성숙도와의 관계를 보면, 1$\mu$g 처리군은 대조군에서와 같은 성숙도를 나타내 차이를 보이지 않았으나, 5$\mu$g처리군에서는 대조군에서 보다 12시간 빠르게 난세포성숙이 완료되어, 엑디스테로이드 처리시 임계농도 이상에서는 난세포조기성숙에 직접적인 영향을 미치는 것으로 나타났다.

• 수산해양기술연구
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• 제45권4호
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• pp.251-259
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• 2009

Swimming crabs, Portunus trituberculatus(Miers) are commercially important off the coasts of Korea, Japan and China. Harvest of swimming crabs has been fluctuated along their distribution ranges. Fluctuations in the interannual harvest of swimming crabs may be correlated with the survival rate during the larval period. The survival rates, intermolt periods, and growth of larval swimming crabs were investigated in the laboratory. Larval swimming crabs are released and undergo development from April to August off the western coast of Korea in the Yellow Sea. Sea surface temperatures off the western coast of Korea during the larval season were used for the laboratory experiments, and ranged from 22 to 26${^{\circ}C}$. Larvae were individually cultured at four different temperatures, 22${^{\circ}C}$, 24${^{\circ}C}$, 26${^{\circ}C}$, and 28${^{\circ}C}$. Zoea molted to megalopa at all temperatures and developed to the first crab stage at 24${^{\circ}C}$, 26${^{\circ}C}$, and 28${^{\circ}C}$. Survival rates from zoea I to the first crab stage increased with increasing temperatures. Intermolt period and the growth rate of the mean carapace length were inversely correlated with temperature. Our research helps understand the changes in survival rate and growth of larval swimming crabs resulting from changing oceanic temperatures. Further, our study suggests that the fluctuations in fishery harvest of swimming crabs off the coast of Korea may be related to changes in larval survival affected by changing ocean conditions.

• Animal cells and systems
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• 제1권1호
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• pp.31-42
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• 1997

The larval stages of Pilumnopeus granulata and the megalopal stage of Pilumnus minutus are described in detail. Comparisons are made with the known larvae of other species of the pilumnid genera, and the provisional key is provided for the pilumnid zoeae. The brachyuran genera Heteropanope, Heteropilumnus, Actumnus, Pilumonopeus, Pilumnus, Parapilumnus, and Benthopanpe are clearly classified on the basis of the zoeal characteristics, such as the lateral carapace spine, dorsal carapace spine, maxillule, and abominal lateral knobs.