• 한국수산과학회지
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• 제49권3호
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• pp.337-342
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• 2016

Sea cucumbers have been an important part of human diets throughout history; demand is increasing every year, making the species a target for coastal resource development. New harvesting technologies have been developed in response to demand, including nursery production and insemination aquaculture, but such methods produce relatively few individuals and productivity per unit area is very small. For example, captures are prohibited during July and August due to the breeding season, and sea cucumbers aestivate during the hot season and hibernate during the cold season, all factors that limit natural-environment production in Korea. Problems with slow growth of sea cucumbers have been encountered in previous rearing experiments. To assess the importance of feeding ecology on sea cucumber growth, we conducted pond-bottom and lantern-net culture experiments. Results showed that sea cucumbers in bottom cultures grew from 3.06 to 102.59 g, but those in lantern cultures only grew from 25.60 to 28.03 g.

• 한국수산과학회지
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• 제56권5호
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• pp.716-720
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• 2023

This study was designed to analyze the effects of reducing water turnover in olive flounder Paralichthys olivaceus farms, focusing on olive flounder growth, decreasing electricity costs, and developing measures to ensure business stability. Daily water turnover was set at 18 in the control group and six in the experimental group. Juvenile fish were reared for 12 months. No significant differences in mean weight were observed between groups until five months. After five months, the mean weight of the control group grew significantly faster than that of the experimental group. Maintaining water turnovers leverl at six turnovers for the first five months after stocking juvenile fish and then increasing water turnover resulted in a 34.4% reduction in electricity costs compared to the control group. This approach presents a potential method to enhance the profitability of olive flounder farms and ensure stable productivity and profitability without sacrificing olive flounder growth.

• 센서학회지
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• 제30권3호
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• pp.154-164
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• 2021

RAS(Recirculating aquaculture system) 방식 또는 바이오플락 기술를 사용한 흰다리 새우의 육상 양식을 통해서 새우 개체의 생존율과 고밀도 생산율을 향상시키기 위한 양식의 원리 및 장치 구성, 국내외 수질 모니터링 센서, 현재의 양식 모니터링 시스템의 문제점 파악 및 미래의 양식 모니터링을 위한 대책을 분석 하였다. 흰다리 새우 양식을 위해서는 수조별 온도, pH, DO, 염도 측정이 기본적으로 필요하며, 암모니아성 질소, 질산성 질소, 아질산성 질소, 생장 관리를 위한 이온성 물질의 측정이 필요하다. 특히 센서재질에 있어서는 SUS304도 부식이 되는 고염도 환경에서 견딜수 있어야 하며, 고탁도 및 부유물질에 의한 생물 부착에 견딜 수 있는 센서가 사용되어야 한다. 또한 내구성 및 측정값 신뢰도, 가격 경쟁력 있는 센서 및 시스템 공급이 필요하다. 바이오플락 양식 환경에서는 고염분, 고부유물 환경에서 견딜 수 있는 센서의 내구성과 데이터 안정성, 신뢰도가 무엇보다 중요하다. 향후 흰다리 새우 및 수산 양식을 위한 최적 양식환경을 확보하기 위해서는 양식 생육 환경 현장의 수질을 측정하고 적정 환경을 결정하며, 자동제어 시스템을 이용하여 제어하고 축적된 데이터를 활용 및 분석하여 지능적으로 관리하는 기술을 개발하는 것이 필요하다.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2001년도 추계 수산관련학회 공동학술대회발표요지집
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• pp.25-25
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• 2001

Generation of transgenic fish acquiring the ability to express desirable phenotypes offers new possibilities for addressing fundamental biological questions, and can also attribute to enhanced aquaculture productivity. I describe here the recent research progress in my laboratory with particular emphasis on the development of fast-growing autotransgenic fish and its chromosome-set manipulation using our experimental organism, the mud loach, Misgurnus mizolepis. (omitted)

• ALGAE
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• 제29권3호
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• pp.217-225
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• 2014

Land-based seaweed (Gracilaria) cultivation systems may provide products with high quality and biosafety for human consumption, as well as for other high value applications. However, a limitation for this land based system is high management costs. The objective of this study was to determine if the management costs for Gracilaria cultivation can be reduced without a decrease in productivity by using $CO_2$ injection along with a high stocking density and high photosynthetically active radiation (PAR), and commercially available fertilizers. When Gracilaria tikvahiae was cultivated at a high stocking density and high PAR, coupled with $CO_2$ enhancement, the productivity was significantly higher than that at a lower stocking density, low light without $CO_2$ injection. We also found that G. tikvahiae grown in a medium of commercially available fertilizer (Jack's Special, JS) showed a similar growth rate and productivity to that grown in von Stosch's enriched (VSE) seawater, while the cost for JS media is only 2% of the cost for VSE. These results suggest that $CO_2$ injection and commercial fertilizer may be a potential way to provide sustainability in land-based Gracilaria cultivation systems.

• 한국기계가공학회지
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• 제19권7호
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• pp.106-111
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• 2020

In the era of the fourth industrial revolution, the application of big data analysis technology is crucial in various industries. In this regard, considerable research is necessary to improve aquafarming productivity, particularly in fish culture, which is one of the primary industries in the world. In this study, a sample experiment using a flop was conducted to improve oyster productivity in fish farms, and a flush was installed in an environment similar to aquaculture farms. Thereafter, the temperature data of the water environment where the formation of burrows considerably improved were collected; the growth rate of burrow seeds was also measured. The gathered experimental data were examined by time series data analysis. Finally, a system that visualizes the analysis results based on big data is proposed. In accord with the results of this study, it is expected that more advanced research on the productivity improvement of oyster aquafarming will be performed.

• 한국수산과학회지
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• 제31권4호
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• pp.477-482
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• 1998

치어의 먹이사료인 동물성 플랑크톤은 단세포조류인 Chlorella를 먹이로 하고 있으며, 우리 나라에서는 현재까지 Chlorella를 연못형 배양조에서 배양하고 있다. 본연구에서는 Chlorella의 생산성을 높이기 위하여 Chlorella 배양 조건 중, 빛의 공급율을 높이는 데에 중점을 두고 여섯 형태의 모형 배양조를 제작하고 Chlorella vulgalis 211-11b의 최대 비증식속도와 생산성을 비교하였다. 모형 배양조 중, ${\mu}_{max}$와 생산성이 가장 큰 것은 HS-Pbr이었으며. 최대 비증식속도와 생산성이 반드시 배양조의 S/V에 비례하지는 않았다.

• 한국수산과학회지
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• 제53권5호
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• pp.725-732
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• 2020

The sudden drop of water temperature in winter is very threatening factor that affects the productivity of farmed fish and the management in aquafarm. In this study, we investigated the effect of low temperature on the survival, oxygen consumption and stress responses of parrotfish Oplegnathus fasciatus due to acute drop of water temperature. The survival rate of parrotfish Oplegnathus fasciatus was 5% at 6℃, 95% at 8℃ and 100% at 10℃ on the 4^th day of exposure in each experimental temperature. Low-lethal temperature for 4days of parrotfish Oplegnathus fasciatus (4 day-LT₅₀) was 6.99℃ (confidence limit, 6.55-7.42℃). Oxygen consumption rate was significantly decreased with decreasing water temperature. Temperature coefficient (Q₁₀) was found to be 4.0 between 10℃ and 8℃ and 0.39 between 8℃ and 6℃. As a result of investigating the stress response according to the drop in water temperature, the concentration of SOD (Superoxide dismutase), cortisol, glucose, total Ig, AST (Aspartate) and ALT (Alanine aminotransferase) increased with decreasing of water temperature. This study would be useful for the management of temperature about cultured fish.

• 한국수산과학회지
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• 제52권5호
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• pp.539-546
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• 2019

The major cultured marine fishes in sea off the coast Gyeongsangnam-do Province, South Korea, were assessed and included 9.3% rockfish Sebastes schlegelii, 7.8% red seabream Pagrus major, and 2.1% rock bream Oplegnathus fasciatus. The number of insurance payments related to disease mortality in cultured fish in 2017 was fourfold that in 2016. Economic loss in aquaculture due to disease in cultured fish is high and represents an important inhibitory factor affecting marine fishery productivity. In 2018, diseases led to severe production losses in several aquaculture species: 40.0% in rockfish, 11.4% in olive flounder Paralichthys olivaceus, 10.0% in filefish Thamnaconus modestus, and 9.3% in red seabream. Fish-parasitic pathogens such as Microcotyle sebastis, Alella spp., and Dactylogyrus spp. enter mainly via the gills and skin surface. Among bacterial pathogens, Vibrio species were most common, with Vibrio harveyi being the dominant species causing infections in these fishes. The bacterium Lactococcus garvieae is thought to exhibit host specificity in fish. The fish species in the present study exhibited a higher tendency for infection by heterologous pathogens than by a single pathogen; therefore, it is necessary to devise new strategies for treating diseases in cultured fish.

• 수산해양기술연구
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• 제60권2호
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• pp.186-193
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• 2024

Most fishing nets used in fish cage aquaculture are made of synthetic fibers such as polyamide (PA) and polyethylene (PE). Therefore, it is challenging to maintain the internal volume of the fish cage due to biofouling, which can increase the load on the cage or reduce dissolved oxygen levels by impeding smooth current flow. To address this issue, research has been conducted to replace conventional synthetic fiber cage nets with brass nets, demonstrating certain benefits such as improved productivity and ease of fish cage management. However, given the need for a more thorough examination of brass fishing net weaving technology and performance, this study assessed the optimal weaving method for brass fishing nets to be used in fish cages. Additionally, it provided essential data for the practical application of brass fishing nets by evaluating their weight, tensile strength, elongation, fatigue resistance, and wear resistance. The study concluded that weaving brass fishing nets using the chain link method ensures durability, ease of installation, and compact storage in a scroll-like form. Moreover, due to their superior fatigue and wear resistance properties, brass nets can offer increased utility if appropriate net diameter and length are selected to compensate for their higher weight per unit area and relatively higher cost compared to existing fiber fishing nets.