• 한국양식학회지
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• 제11권3호
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• pp.303-310
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• 1998

난황형성 단계에 있는 암컷 어미에게 갑상선 호르몬인 3,5,3'-triiodo-L-thyronine ($T_3$)를 20 mg $T_3$/kg 체중으로 주사하여 출산된 조피볼락 자어를 대조구인 sham구 및 control구 자어와 함께 30일간 사육하면서 성장과 생존율을 비교하였다. 자어에게는 출산후 5일째까지 rotifer를 공급하였고, 6~15일까지 rotifer와 Artemia nauplii를, 이후 30일까지 Artemia nauplii와 넙치용 배합사료를 혼합공급하였다. 출산후 자어의 성장은 대조구들에 비해 $T_3$구에서 유의하게 빨랐으며, 생존율 역시 T하(3)구가 대조구들 보다 유의하게 높았다. 실험종료시 치어의 비만도는 $T_3$구가 control구에 비해 다소 낮았고, sham구에 비해서는 유의하게 낮았다. 이상의 결과, 조피볼락에 대한 $T_3$의 모체주사는 모체에서 유래된 외인성$T_3$가 초기 출산자어의 생리활성을 증진시켜, 자치어의 성장과 생존율 향상에 도움을 줄 수 있는 것으로 평가되었다.

• 한국패류학회지
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• 제19권2호
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• pp.95-106
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• 2003

The compositions of amino acid in 6 monocultured benthic diatoms used in aquaculture of Haliotis discus hannai were analyzed, and effects of 15 artificial synthetic amino acids on the settlement and metamorphosis of H. discus hannai larvae. Results showed that the content of L-aspartic acid was highest in all diatoms, and that of L-glutamic acid was second high. In experiment using settlement slat without benthic diatom attached, the highest settlement rate (33.3 ${\pm}$ 8.8%) was obtained with L-glutamic acid, and a higher value (16.7 ${\pm}$ 3.3%) was found with L-aspartic acid at 24 h after experimental commencement, compared to that of control (8.6 ${\pm}$ 5.1%). 80 h later the metamorphosis rates of L-glutamic acid (86.7 ${\pm}$ 10.7%) and L-aspartic acid (80.0 ${\pm}$ 3.3%) groups were higher than control group(0) and other amino acids significantly. The response rate of L-glutamic acid was the highest (62.0%), and those of L-aspartic acid (30.0%) and L-threonine (25.3%) groups were also significantly higher than control group. In the experiment using settlement slat with benthic diatom attached, the best effect of various amino acids on induction of larval settlement was obtained with L-glutamic (82.0 ${\pm}$ 6.9%) and L-aspartic acid (78.7 ${\pm}$ 5.1%) at 24 h after experimental commencement. The settlement rates of L-histidine, L-leucine, L-lysine, L-methionine, L-phenylalanine, and L-tyrosine groups were significantly lower than control group. The same differences in the metamorphosis rate at 56 h after experimental commencement and in the response rate were found. It should be noted that after 80 h the metamorphosis rates of L-histidine (74.0 ${\pm}$ 12.0%) and L-lysine (87.0 ${\pm}$ 8.8%) declined rapidly compared to those of 56 h (8.0 ${\pm}$ 12.0%; 7.7 ${\pm}$ 12.0%).

• Animal cells and systems
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• 제12권4호
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• pp.297-304
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• 2008

Morphology and distribution of the minute tubercles projected on the skin surface of larvae with its development were observed in the Korean bitterling, Acheilognathus somjinensis. The minute tubercles appeared to be two distinct morphologies, hemispheric or scaly and vestigial structures. Just after hatching, the epidermis of the larvae consists of a thin single cell layer having smaller basophilic flat or round-flattened basal cells. As the larvae grow, the epidermis contains more small flat cells and large epidermal cells which are round and hemispheric, or scaleshaped, called minute tubercles. They are distributed over the anterior part and most part of yolk sac, posterior region of yolk sac and the body region. Vestigial epidermal cells, another minute tubercle, occur only in the caudal fin-fold region, which they are shrunken and flattened, causing the cell boundary to be unclear. They increase in number and height from just to 5 days after hatching, but they become reduced as the larvae develop gradually. The required time for those disappearance was different each by regional body: at day 20 after hatching in the anteriormost part of yolk sac, and day 11 after hatching in the posterior part of yolk sac and the body, and day 21 after hatching in two regions such most part of the yolk sac and the caudal finfold regions.

• 한국응용곤충학회지
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• 제32권4호
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• pp.395-406
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• 1993

본 실험은 성페로몬 실험에 필수적인 조명나방의 인공사료와 대량사육 체제를 개발하기 위하여 수행되었다. 영양원으로서 효모, Wesson 염, 비타민 등의 중요성을 알아보기 위하여 그들을 사료에서 삭제 또는 첨가하였다. 또하 적절한 사육방법을 고안했으며 번데기의 암경화현상에 영향을 미치는 요인도 알아 보았다. 효모의 첨가는 용무게와 용화율을 높여 주었으나 Wesson염의 첨가는 암컷 용의 무게를 감소시켰다. 효모의 대용으로 사용된 비타민은 어린 유충의 생존율을 높여 주었으나 용무게에서는 효모첨가사료의 경우 보다 가벼웠다. 용화장소로서 골판지는 매우 좋은 결과를 보였고, 용의 암경화율은 유충의 발육속도가 빠를수록 높았다.

• Current Research on Agriculture and Life Sciences
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• 제32권4호
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• pp.185-188
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• 2014

The movement, survival, and weight gain of Helicoverpa armigera $H{\ddot{u}}bner$ (Lepidoptera: Noctuidae) first instar larvae were studied on CB9, CB10 and SR05 cotton varieties under field conditions. The neonate H. armigera were released on the cotton varieties at the squaring stage of the plants and, after a period of 72 hours, the survival, weight gain, and final location of the larvae were observed. While the different cotton varieties had no effect on the survival and weight gain of the larvae, the release locations on the cotton varieties had a significant influence on the larval survival and weight gain. The larvae fed small squares of the cotton varieties were significantly heavier and showed a higher mortality than the larvae fed leaflets and mature leaves. For the cotton varieties in this study, the larvae released on leaflets showed a significantly higher rate of recovery compared to the larvae released on mature leaves and squares. This study also found that that the larvae on leaflets did not move up or downward unlike the larvae on mature leaves and squares. This information on the foraging behavior of larvae on cotton varieties will assist researchers to interpret field data and thereby help with the development of pest management decisions.

• International Journal of Industrial Entomology and Biomaterials
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• 제46권2호
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• pp.34-40
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• 2023

As agricultural production increases due to population growth, agricultural by-products that are generated at all production stages increase commensurately. Black soldier fly (BSF) (Hermetia illucens) treatment has potential as an environmentally friendly process to combat the environmental pollution caused by agricultural by-products. This study examined the utilization of BSF larvae in the decomposition of the by-products of apples and mandarins, fruits commonly produced in South Korea. The BSF test larvae were fed apple pomace or mandarin waste, and the control larvae were fed calf feed. Larval weight and size were measured at 4-day intervals until larvae reached the pre-pupal stage. Larval development time, survival rate, and BSF fecundity rate were calculated for all three substrates. Waste reduction and bioconversion ratios were also calculated. The developmental time of larvae fed with apple pomace and mandarin waste was greater than that of the control larvae. The average weight of larvae fed with the fruit by-products was less than that of the control. There was no significant difference in the survival rate of BSF larvae or the fecundity rate of BSF between the substrates used in this study. BSF larvae decomposed 48.0% and 61.5% of apple pomace and mandarin waste, respectively. The bioconversion efficiency rates of BSF larvae fed with apple pomace and mandarin waste were 9.1% and 12.1%, respectively. These results indicated that decomposition of single fruit by-products by BSF larvae is an environmentally friendly and effective bioconversion process.

• 한국해양생명과학회지
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• 제3권2호
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• pp.67-73
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• 2018

본 연구는 수온, 염분, 사육밀도 및 혼합 먹이생물 공급량과 같은 환경요인이 왕우럭 Tresus keenae의 유생사육 시 생존 및 발생에 미치는 영향을 조사하기 위하여 수행하였다. 연구 결과, 왕우럭 유생사육의 최적 조건은 수온 20℃에서 24℃, 염분 30 psu, 사육밀도 1 ml당 5개체 및 먹이생물 I. galbana, C. simplex 및 T. suecica 혼합 공급량 10×10⁴ 세포/ml이였다. 본 연구 결과를 통해 밝혀진 왕우럭 유생 최적의 사육 환경요인은 빠른 성장 및 높은 생존을 통해 생산성 향상에 기여하리라 생각된다.

• 한국수산과학회지
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• 제47권5호
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• pp.630-636
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• 2014

To investigate the characteristics of hybrid eggs and larva produced by olive flounder Paralichthys olivaceus females and starry flounder Platichthys stellatus males, we examined the developmental speed of hybrid eggs at different water temperatures. The developmental speed of hybrid eggs tended to increase with increasing water temperature. Specifically, the hatching times were 91 hrs, 62 hrs and 43 hrs at $10^{\circ}C$, $15^{\circ}C$ and $20^{\circ}C$, respectively. The mean biological minimum temperature of the hybrid was $1.3^{\circ}C$, which is in between that of the olive flounder and the starry flounder. In high water temperatureseasons, slower growth was observed in hybrids of the starry flounder which is a coldwater fish.

• Fisheries and Aquatic Sciences
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• 제20권12호
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• pp.31.1-31.11
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• 2017

Background: Liver-expressed antimicrobial peptide-2 (LEAP-2) is an important component of innate immune system in teleosts. In order to understand isoform-specific involvement and regulation of LEAP-2 genes in mud loach (Misgurnus mizolepis, Cypriniformes), a commercially important food fish, this study was aimed to characterize gene structure and expression characteristics of two paralog LEAP-2 isoforms. Results: Mud loach LEAP-2 isoforms (LEAP-2A and LEAP-2B) showed conserved features in the core structure of mature peptides characterized by four Cys residues to form two disulfide bonds. The two paralog isoforms represented a tripartite genomic organization, known as a common structure of vertebrate LEAP-2 genes. Bioinformatic analysis predicted various transcription factor binding motifs in the 5'-flanking regions of mud loach LEAP-2 genes with regard to development and immune response. Mud loach LEAP-2A and LEAP-2B isoforms exhibited different tissue expression patterns and were developmentally regulated. Both isoforms are rapidly modulated toward upregulation during bacterial challenge in an isoform and/or tissue-dependent fashion. Conclusion: Both LEAP-2 isoforms play protective roles not only in embryonic and larval development but also in early immune response to bacterial invasion in mud loach. The regulation pattern of the two isoform genes under basal and stimulated conditions would be isoform-specific, suggestive of a certain degree of functional divergence between isoforms in innate immune system in this species.

• 한국응용곤충학회지
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• 제13권2호
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• pp.83-88
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• 1974

이화명충(Chilo suppressalis Walker)에 대한 벼 품종별 저항성을 알기 위하여 통일(수원 21교, 진흥, IR747, 수원 229호 등 58개 품종을 공시하여 시험을 하였다. 실내시험에서 유충기간은 품종간 대차없었다. 유충체중은 감수성 품종에서는 34.4mg이었으나 저항성 품종은 18.0mg이었으며 용화율도 저항성 품종에서 높았다. 산난선호성 시험에서는 수원 240호 천추락 등이 낮은 선호성을 보였고 포장조사에서는 Tetep, 망게스 찰 IR747등이 낮은 피해경률을 나타내었다.