• International Journal of Industrial Entomology and Biomaterials
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• 제1권2호
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• pp.137-141
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• 2000

To determine effects of temperatures and photoperiods on larval development of the mulberry longicorn beetle, Apriona germari, the larvae were reared at various rearing temperatures and under the various photoperiods on an artificial diet. The larval period of A. germari was extended as long as the temperature was lowered. Also the larval development in terms of length and weight of larvae was increased. However, survival rate during larval stage significantly decreased at 15$^{\circ}C$ and $20^{\circ}C$ than at $25^{\circ}C$ and $30^{\circ}C$. The results indicated that the favorable temperature for artificial diet rearing of A. germari fell at least above $25^{\circ}C$ constantly. In photoperiod conditions, survival rate and larval development for A. germari were obviously most effective under a photoperiod of 14L:10B. As a result in artificial diet rearing of a. germari at $25^{\circ}C$ and under a photoperiod of 14L:10D was mostly favorable in terms of larval development and period.

• Animal cells and systems
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• 제12권4호
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• pp.279-286
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• 2008

Development and distribution of larval Dungeness crab, Cancer magister Dana, 1852 were investigated in southeastern Alaska from late May to mid-September in 2004. Larvae were collected during daylight hours at three inner and two outer Glacier Bay stations at the two different depths in the water column, above and below the thermocline. Larval density decreased dramatically for three larval stages, zoeae I(ZI), zoeae IV, and zoeae V(ZV), but relatively little for zoeae II and zoeae III. ZI predominated at all stations in late May and were collected until late July. Larval stages progressed seasonally from ZI to ZV and density decreased from ZI through ZV. The densities of each zoeal stage at the inner and outer bay stations and at the shallow and deep depths were similar. The density of each larval stage above(shallow) and below(deep) the thermocline and between inner and outer bay stations were not significantly different. The occurrence of larval Dungeness crab is dramatically later than in other parts of the species range, in that larvae appear in abundance beginning in late May. The pattern of spatial distribution of larval stages for the inland waters of Alaska was also markedly different than the patterns reported for Dungeness crab larvae from other parts of the species range, in that the early and intermediate stages occurred within inland waters; from British Columbia to California these larval stages increase in abundance with distance offshore.

• 한국양식학회지
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• 제20권3호
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• pp.194-198
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• 2007

Reproductive traits of Palaemon gravieri such as embryo size, number of embryo (fecundity), incubation period, larval development mode, larval development period, larval survival and larval growth were described and compared to analyze the correlation among those traits. Embryo volume is a primary factor determining other ensuing reproductive features. Egg volume was $0.042mm^3$ in the first developmental stage. Embryo volume in P. gravieri was comparatively small which is indicative of great number of embryo (y = 3.0161x + 0.0185 $R^2$ = 0.74 positive isometric relationship) and relatively long incubation period. Larvae survived from zoea 1 to post-larvae and it took 45 days at $22^{\circ}C$. Survival rate of the larvae was rather great in the early stage and thereafter steadily decreased. Daily growth rate of larvae in P. gravieri at $22^{\circ}C$ was 0.0195 mm on average. They grew steadily as time went by. Incubation period was between 10-14 days at $22^{\circ}C$. Larval development mode was almost complete planktotrophic. PNR (point of no return) appeared to be the third day on average. Survival rate of larvae without feeding declined rapidly between 3 and 4 days. Larval development period and stage frequency were 23-30 days and 11 stages which imply prolonged larval period and high mortality. The pattern of brood production followed fast successive parturial pattern. Most ovigerous female had mature ovary when they performed parturial molt soon after hatching (larval release).

• Animal Systematics, Evolution and Diversity
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• 제5권2호
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• pp.121-137
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• 1989

실험실에서 사육한 발콩게의 유생기를 자세히 기술, 도시하였다. 본 종은 5 zoea와 1megalopa 유생기를 가지며, 수온 25$^{\circ}C$에서 megalopa와 제1기 crab은 부화후 각각 21일과 31일 만에 나타났다. 엽낭게속의 유생은 갑각에 대한 이마가시 길이의 상대비에 의하여 콩게아과의 타 속과 달랑게아과의 타 아과의 유생들로부터 구별될 수 있다. 발콩게의 유생은 엽낭게의 유생과 형태적으로 매우 유사하나 유생의 크기와 부속지의 강모식의 차이에 의해 구별될 수 있다.

• 한국발생생물학회지:발생과생식
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• 제16권2호
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• pp.107-112
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• 2012

Early growth, the rate of yolk sac absorption, and nucleus size in liver parenchymal cells were correlated with the nutritional status of first feeding larval haddock, Melanogrammus aeglefinus. Larvae that successfully began exogenous feeding maintained high growth rates, delayed yolk sac resorption, and had larger hepatocyte nuclear sizes than starved larvae. At 10 days post hatch (DPH) the cumulative mortality in the starved larval haddock group was 100%. The area of the hepatocyte nuclei in starved larvae gradually decreased, reaching its lowest value by 9 DPH. Our results support the current practice of providing the first food supply at 3 DPH. Hepatocyte nuclear size can be used to assess larval haddock nutrition status, and may be a good criterion for assessing the success of transition from endogenous to exogenous feeding.

• 한국응용곤충학회지
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• 제28권3호
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• pp.113-119
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• 1989

금잔화, 들깨풀, 수국등 10종의 야생식물잎의 추출물이 담배나방(Heliothis assulta) 유충의 발육과 성충의 산란에 미치는 영향을 조사하였다. 그 결과 유충이 높았으며 대부분 1영과 2영 기간중 먹지않기 때문이다. 여기서 살아남은 유충들도 발육기간 및 탈피횟수는 증가하는 경향을 보였다. 이중 갈매나무와 때죽나무의 추출물은 성충의 산란도 상당히 억제하였다.

• Animal cells and systems
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• 제12권3호
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• pp.171-180
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• 2008

The complete larval development of Pagurus japonicus(Stimpson) is described, based on laboratory rearing. The species has four zoeal stages and a megalopa. The larvae are described and illustrated, and detailed comparisons with other pagurid larvae in the Korean coast are made.

• 한국동물학회지
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• 제36권1호
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• pp.67-76
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• 1993

The lanral characters of Petrolisthes japonicus (De Haan, 1849), Porcellanidae, were described and illustrated. The lanral development of P. juponicus includes the two zoeal and one megalopal stases. The first and second zoeal stases lasted about 4 and 10 days, respectively. It took about 14 days to attain megalopa from hatching-The larval characteristics of P. japonicus were compared with those of other knouts species of Petrolisthes. Consequently, the lanrae of P. japonicus are more closely related to P elongatus and P ornutus than other Petrolisthes species, but the present species can be distinguished from these Petrolisthes species by morphological characteristics.

• Animal cells and systems
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• 제14권2호
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• pp.115-123
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• 2010

The complete larval development of Rhinolithodes wosnessenskii Brandt, 1848 is described, based on laboratory rearing. The species has four zoeal stages and a megalopa. The zoeas of R. wosnessenskii are readily distinguished from all other described zoeas of the subfamily Lithodinae by having a middorsal spine of the posterior margin of the carapace.

• Fisheries and Aquatic Sciences
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• 제27권8호
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• pp.475-487
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• 2024

Larviculture of commercially important aquaculture species faced limitations associated to the incomplete understanding of larval nutrition and the inability to total replacement of live feeds by formulated diets at the early larval stage. The main challenges to alternatives of live feed in larval fish culture are related to the inherent behaviors of the larvae and the incomplete knowledge and practice leading to the inefficiency of using micro diets. Although significant achievement has been reached in the complete replacement of live feeds by formulated micro diets in freshwater species and marine shrimps, its success is far from complete in marine finfishes. However, recent progress in biotechnological advances in manufacturing process and advanced knowledge of the nutritional necessities of larvae indicated improvements in the field. A range of technologies in the manufacturing of micro diets for larval fish are in place currently. To this end, several achievements of substituting live feeds with formulated micro diets at later stages of larval development have been reported by various researchers providing a clue on the prospects for the future. Therefore, the objective of this review is to compile existing information on the challenges of substituting live feeds by formulated diets in the past and prospects for future development.