• Animal cells and systems
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• v.12 no.4
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• pp.287-295
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• 2008

Variations of larval abundance and hatch timing of Dungeness crabs, Cancer magister Dana 1852, were investigated. Dungeness crab larvae were monthly collected at 16 stations arrayed in four transects, Upper Chatham, Icy Strait, Cross Sound, and Icy Point, in southeastern Alaska from May to September 1997-2004. Larval abundance at all transects was the highest in June except in the Icy Point transect. Larval abundance was the highest in the Icy Strait transect, moderate in the Upper Chatham and Cross Sound transects, and the lowest in the Icy Point transect. Zoeae I(ZI) was predominated in May; thereafter ZI decreased and late zoeal stages occurred. In May and June, small numbers of late stage larvae unusually co-occurred with ZI in three transects. These late stage larvae may have been transported from where hatching occurs earlier. The timing of ZI occurrence varied interannually and was related to degreedays during the egg incubation period of Dungeness crabs: later larval hatching in 1997 and 2002 when temperatures were colder, while earlier larval hatching in 1998 when temperatures were warmer. The distribution patterns of Dungeness crab larvae in southeastern Alaska were markedly different from those reported from other areas of the species distribution ranges: larvae occurring much later in the year, and late stage larvae occurring in inland waters.

• Korean Journal of Ichthyology
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• v.4 no.1
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• pp.20-28
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• 1992

The influence of starvation on morphological change and survival rate of the left eye flounder larvae was examined at the KORDI laboratories in March, 1990. 1. The larvae of left eye flounder began of feed on rotifers in 5 days after hatching. In case of non-feeding, all of the larvae died in 11 days after hatching. The larvae which fed 1 day after the normal first feeding schedule grew normally but 100 of the larvae died in 14 days when the feeding was delayed for 2 days after hatching. 2. With the exhaustion of the yolk, the total length, body length, myotome height and gut height of unfed larvae decreased. Gut height is the most decreased demensions while starving. 3. The ratio of gut height to myotome height in unfed larvae has declined most rapidly compare to other demensions during the starvation. At 13 days after hatching, the ratios of these between fed and unfed larvae were 0.797 and 0.467, respectively. 4. The morphology of starving larvae were characterized as sharpened jaw, projected edge of lawer part of clavicle and slender gut.

• Journal of Animal Reproduction and Biotechnology
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• v.35 no.3
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• pp.223-231
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• 2020

Karyotype analysis is a major work in the process of triploid abalone production for the purpose of productivity and quality improvement. However, the metaphase spreads for karyotype analysis have been prepared just from the larvae at trochophore stage, which has restricted the spectrum of sample correction inhibiting more efficient analysis. Here, we investigated the feasibility of preparing metaphase spreads from the larvae at veliger stage that is the next developmental stage of trochophore. For this, diploid and triploid larvae at trochophore and veliger stages from Pacific abalone (Haliotis discus hannai) were subjected to metaphase spread preparation and its efficiencies were measured and compared each other. As the results, although the efficiencies of metaphase spread preparation were significantly lower in the larvae at veliger stage compared to the ones at trochophore stage regardless of ploidy status, we found that the preparation of metaphase spreads, which showed the clear chromosomal images containing the normal number of chromosomes, was possible from the veliger stage larvae. On the other hands, all larvae used in this study regardless of developmental stage and ploidy did not show colchicine sensitivity. Moreover, no significant difference was observed in cell cycle distribution of the cells comprising larvae between two developmental stages regardless of ploidy status. These suggested that the details of protocol to prepare metaphase spreads from abalone larvae should be optimized depending on its developmental stages. Taken together, we demonstrated the feasibility of preparing metaphase spreads from H. discus hannai veliger stage larvae for karyotype analysis.

• Journal of Environmental Science International
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• v.33 no.2
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• pp.187-191
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• 2024

This study aimed to investigate the effect of treating environmental purification insect larvae to pig manure on crude ash contents and ammonia production. The experiment set up consisted go two groups: 1 kg of each 3^rd instar TM (Tenebrio molitor) and 3^rd instar PBS (Protaetia brevitarsis seulensis) larvae in Experiment 1 or 3^rd and 4^th instar of HI (Hermetia illucens L.) larvae in Experiment 2 were treated with 5 kg of pig manure. In Experiment 1, the crude ash content was higher in TM larvae-treated pig manure at days 0 and 5 (p>0.05), but was similar to that in PBS larvae-treated pig manure over (p>0.05). Ammonia production was observed at day 0 of TM and PBS larvae-treated pig manure (p<0.05), but did not occur thereafter. For Experiment 2, there was significant difference in crude ash content of 3^th and 4^th instar HI larvae-treated pig manure on day 15. Additionally, ammonia production was found in 3^th and 4^th instar HI larvae-treated pig manure at days 0 and 5, but did not continue over time. In conclusion, treating TM, PBS and HI to pig manure changed the crude ash contents and reduced ammonia through the ability to decompose pig manure. Thus, environmental impact can be minimized using environmental purification insect larvae.

• Korean journal of food and cookery science
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• v.31 no.5
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• pp.534-543
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• 2015

Recently, the Tenebrio molitor larva was recognized as a novel food ingredient by the Ministry of Food and Drug Safety in Korea. Accordingly, we investigated its physical and sensory characteristics to establish the cooking conditions that may increase the demand of T. molitor larvae as a food. In this study, T. molitor larvae were cooked by various methods such as hot air dry, oven-broil, roast, pan fry, deep fry, boil, steam, and by microwave. In the physical evaluation of texture, the hardness and fracturability values were highest when larvae were cooked in the microwave. The adhesiveness, springiness, and chewiness values were highest when larvae were boiled. Boiled and steamed larvae had the highest lightness (L value), while oven-broiled larvae had the highest redness (a value) and yellowness (b value) values. Sensory evaluations assessed the appearance, aroma, flavor, and texture of cooked T. molitor larvae. Steamed and boiled larvae sizes were significantly large and the form was well preserved similar to fresh larvae. The moisture heat cooked (steamed and boiled) T. molitor larvae had the aroma and flavor of steamed corn, canned pupa, and boiled mushroom. In case of oven-broiled T. molitor larvae, the aroma and flavor of mealworm oil, seafood, sweet and roasted sesame were higher than in those cooked by other methods. In texture among sensory evaluation, the hardness and crispiness were the highest in the hot air dried and oven-broiled larvae, whereas juiciness was significantly higher in the boiled and steamed. Accordingly, we suggest that oven-broiled T. molitor larva will be prefered by consumer, due to its the rich aroma and flavor.

• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.93-94
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• 2003

To investigate the food organisms of the Acentrogobius elongata during the juveniles stage, the stomach contents of fish, captured in the intertidal zone of Chungchongnam-do Sochon-gun Su-myon Dodun-ri between on early in June from the end of May 2000, were observed. Total length of the fingerings of A. elongata was 1.0~3.0cm size, and the participation rate of feeding was 68.6%. Main food organisms were such as copepods, shrimp larvae, polychaete larvae, and these occupied more than dry weight 4%. Copepods among them dominated the most quantitys by average 64.6%, and food organismsms appeared by order of polychaete larvae and shrimp larvae etc.. Therefore, most important food organisms of fingerlings stage of A. elongata were copepods, polychaete larvae, shrimp larvae etc.

• The Korean Journal of Ecology
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• v.13 no.1
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• pp.19-24
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• 1990

The effects of insect growth regulator Dimilin which interfere with the synthesis of chitin in the cuticle of insect larvae were investigated at various concentrations using the crab larvae of Hemigrapsus sanguineus. The larvae were cultured at control, 0.5, 1, 5 and 10 $\mu g$ Dimilin solutions and three replicate experiments were carried out to give correct analysis. Significant differences in percent mortality have occurred between control and 10$\mu g$ when the larvae were exposed to Dimilin whereas no differences were found between 5 and 10$\mu g$ Dimilin concentrations. If lethal concentration is defined as concentration at which less than 10 percent of crab larvae reach to the last zoeal stage from hatching it can be concluded that insect growth regulator Dimilin is lethal to the larvae of Hemigrapsus sanguineus at 5 and 10$\mu g$ Dimilin.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.05a
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• pp.359-360
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• 2002

To investigate the food organisms of the Tridentiger trigonocephalus during the juveniles stage, the stomach contents of fish, captured in the intertidal zone of Chungchongnam-do Sochon-gun Su-myon Dodun-ri between on early June from end if may 1999, were observed. Total length of the juveniles of T. trigonocephalus was 5.5mm∼9.0mm size, and the participation rate of feeding was 68.5%. Main food organisms were such as copepods, amphipods, shrimp larvae, polychaete larvae, and these occupied more than dry weight 2%. Copepods among them dominated the most quantitys by average 67.5%, and next, food organismsms appeared much by order of polychaete larvae and shrimp larvae etc.. Therefore, most important food organisms of juvenile stage of T. trigonocephalus were copepods, polychaete larvae, shrimp larvae etc.

• Journal of Environmental Health Sciences
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• v.23 no.1
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• pp.14-17
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• 1997

A total of 93 specimens of Astroconger myriaster were purchased from the Chungmu fishery market at the south sea area during the period from October 1 to November 25, 1996. Specimens were examined for the infection status with larvae anisakid. Anisakid larvae were collected from viscera, muscle, omenturn and liver. Eight hundred four larval anisakids sorted from 93 specimens of A. myriaster ranged from 9.0 to 26.5mm in their body length. They were classified based on morphological and morphometric observations as follows Anisakis type 1 larvae (465 larvae, 57.8%: positive rate), Contracaecum type D(129, 16.0%), Contracaecum type A(90, 11.2%), Anisakis type 11(60, 7.5%), Phapidascaris(3, 0.4%) and unknown type(57, 7.1%).

• Korean Journal of Veterinary Research
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• v.11 no.2
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• pp.157-161
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• 1971

This experiment was undertaken in order to investigate whether chicken can serve as a carrier for swine lungworm, Metastrongylus apri. The results abtained are summerized as follows: All chickens which were fed the infective larvae of M. apri, in the form of infected earthworm (Eisenia foctida) excreted appreximately 4.4 to 5.4 percent of the infective larvae in their feces between 2 to 10 hours after dosing. The larval excretion was marked especially during the first 2 hours. A few (0.10~0.12%) larvae were detected from the intestinal wall of chickens by pepsin-digestion method on a day after dosing, but no further migration or development of the larvae was observed. The larvae which had passed through the digestive tract of chickens retained their viability and produced characteristic lungworm disease when inoculated to guineapigs. From these results, it may he concluded that the chicken can serve as a carrier for the infective larvae of M. apri.