• Journal of fish pathology
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• v.17 no.1
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• pp.57-66
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• 2004

Effects of oral administration with fermented product from sewage in land-based seawater fish farm on haematological disturbance in the olive flounder, Paralichthys olivaceus was investigated. After 4 weeks of conditioning with a basal diet, fish were divided into 4 groups and provided experimental diet (0.1, 0.5, 1.0 and 2.0%) supplement of fermented sewage for 80 days. Proximal analysis was performed for the product of sewage which was fermented by lactic acid and yeast. RBC count, hemoglobin concentration and hematocrit value were increased according to the treated periods, however, no statistical difference was observed between control and treatment groups. There were no significant difference in serum organic, inorganic compounds and enzyme activities between control and treatment groups. This study hypothesized that the supplement of fermented product from sewage in land-based seawater fish farm might be an additive supplement for source of fish diet in view of haematological examination. Recycling of the sewage may be an economic artificial sources of diet for fish aquaculture practices.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.9 no.1
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• pp.30-39
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• 2004

In order to understand the environmental impact of marine cage fish farms, we measured the vertical fluxes of particulate to the sediment, the distribution of organic carbon in core samples, sediment oxygen consumption rate (SOD), and macrobenthos with increasing distance from a fish cage in Miruk island located in Tongyong. The experiment was performed in August 2003. Measured values gradually decreased with distance, indicating that the organic matter in the sediment derived from the fish farm. The dominant macrobenthos species were Tharyx mulifilis, Lumbrineris longifolia, Sigambra tentaculata, and Capitella capitata, occupying 88% of the total population. Capirella capirata, an opportunistic polychaete species, were especially abundant between 0 to 5 m radius range. The estimated impact regions of organic matter enrichment based on sediment consilmption rates and compositions of macrobenthos were in good agreement. Most organic matter derived from the fish farm was deposited within a 10 m radius and then dispersed horizontally to nearby (at least 50 m) surface sediment. The vertical organic carbon fluxes to the sediment at the fish farm were higher by a factor of two than those outside the area. The remineralization organic carbon in the upper sediment layer was estimated to be 50% (1.07 g C m$^{-2}$ day$^{-1}$ ) at the fish farm. In contrast, outside the area, 30% (0.30 g C m$^{-2}$ day$^{-1}$ ) of organic carbon was recycled and the remaining 70% was deposited to the deep sediment layer.

• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.6
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• pp.536-544
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• 2012

It is necessary to study the material circulation of coastal ecosystem according to aquacultural activity in order to induce the sustainable production of aquaculture and the fishery environment for the useful use. Hence, it is essential to make an exact assessment for the sedimentation release flux at the sediment-water interface in the aquafarm. Sediment oxygen demand and dissolved inorganic nitrogen release fluxes were compared using in-situ and laboratory incubational examination. Sediment oxygen demands were 116, 34, and $31\;mmol\;O_2\;m^{-2}\;d^{-1}$ (in-situ incubation), 52, 17, and $15\;mmol\;O_2\;m^{-2}\;d^{-1}$ (Core incubation) and dissolved inorganic nitrogen release fluxes were 7.18, 7.98, and $1.78\;mmol\;m^{-2}\;d^{-1}$ (in-situ incubation), 3.33, 3.74, and $1.96\;mmol\;m^{-2}\;d^{-1}$ (Core incubation) at Tongyeong finfish, Yeosu finfish, and Wando abalone cage farms, respectively. Consequently, in-situ incubation results showed two times higher than laboratory examination. We compared the material flux at the sediment-water interface of each farm and the characteristics between two different kinds of material flux examination.

• Proceedings of the Korean Aquaculture Society Conference
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• 2001.12a
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• pp.255-256
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• 2001

• Journal of Navigation and Port Research
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• v.34 no.10
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• pp.793-797
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• 2010

The depleting fishes resource and water pollution in coast has a decisive effect on the fish farm and fisheries. For solving these problems the fish farms are moving to the offshore. The fish farms in offshore have to design the strong mechanism as compared with cost's fish farm, and operate by the remote feeding system and monitoring system for safety and management.. This paper describes a remote feeding system for fish farms in offshore. The amount of feed is depending on temperature and fish weight. The fish farm temperature is changed extremely in offshore than on land side. This paper described that the feed amount is calculated automatically according to temperature and fish weight, and the remote feed system. The performance of remote feed system is tested with model.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.10a
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• pp.259-260
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• 2001

양식장에서 사육수의 염분변화는 어체의 삼투압변화를유도함으로써, 어류는 항상성을 유지하기 위하여 삼투압조절 즉, 수분과 세포내 염류 및 영양물질의 농도를 조절하려고 한다. 최근에는 해산어류의 삼투압 조절기능을 응용하여 담수순화 양식을 시도하려는 연구가 숭어에서 수행된 바 있으나(장과 허, 1999; 허와 장, 1999), 이외의 해산어류에 관한 삼투압조절 기능을 연구한 결과는 부족한 실정이다. (중략)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.377-378
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• 2001

양식과정중 마취는 어류를 고정시키거나, 인공 채란, 종묘 입식, 출하시 수송 및 선별과 같은 일상적인 취급에서 스트레스를 감소시키기 위한 방안으로 많이 이용되어 왔다(Westernized, 1993). MS-222는 어류에 사용되는 가장 일반적인 마취제로 물에 잘 녹는 하얀 결정상의 가루로 빠른 마취를 일으키고 회복시간은 짧다(Bourne, 1984). 그러나 일반 어류 양식장에서 널리 사용되기에는 가격이 비교적 비싼 편이다. (중략)

• Journal of Internet Computing and Services
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• v.24 no.1
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• pp.61-69
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• 2023

Recently, as the fishery resources are depleted, expectations for productivity improvement by 'rearing fishery' in land farms are greatly rising. In the case of land farms, unlike ocean environments, it is easy to control and manage environmental and breeding factors, and has the advantage of being able to adjust production according to the production plan. On the other hand, unlike in the natural environment, there is a disadvantage in that operation costs may significantly increase due to the artificial management for fish growth. Therefore, profit maximization can be pursued by efficiently operating the farm in accordance with the planned target shipment. In order to operate such an efficient farm and nurture fish, an accurate growth prediction model according to the target fish species is absolutely required. Most of the growth prediction models are mainly numerical results based on statistical analysis using farm data. In this paper, we present a growth prediction model from a stochastic point of view to overcome the difficulties in securing data and the difficulty in providing quantitative expected values for inaccuracies that existing growth prediction models from a statistical point of view may have. For a stochastic approach, modeling is performed by introducing a Gaussian process regression method based on water temperature, which is the most important factor in positive growth. From the corresponding results, it is expected that it will be able to provide reference values for more efficient farm operation by simultaneously providing the average value of the predicted growth value at a specific point in time and the confidence interval for that value.

• Journal of Navigation and Port Research
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• v.30 no.8 s.114
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• pp.721-727
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• 2006

Ammoniac nitrogen excretion is not able to be removed in ocean fish farm. It is the reason for fish being dead in large quantities or declining feeding activity that ammoniac nitrogen is not removed efficiently in ocean fish farm. Because of declining with feeding activity, it is true that feed is wasted for the present. To solve this problem, NH3, one of environment factors in ocean fish farm, monitoring system is suggested to be formed in this paper.

• Journal of fish pathology
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• v.35 no.1
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• pp.1-25
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• 2022

The aquaculture industry has developed rapidly over the last three decades and is an important industry that supplies over 15% of humans' animal protein intake; therefore, there is a need to increase production to meet the continuous demand. The fish cage farms on the southern coast (Kyengsangnam-do and Jeollanam-do) of Korea are critical resources in aquaculture because they account for approximately 90% of the national total fish cage farms by water area ratio. However, the current aquaculture environment is being gradually affected by climate change, which is a global issue, and its effects are expected to intensify in the future. Therefore, it is urgently imperative to accurately evaluate the effects of climate change on South Korean aquaculture industries and to develop social and national strategies to minimize damage to the fishing industry. The damage to fish farmed in cage farms on the southern coast is increasing annually and the leading causes are high and low water temperature and red tides, which are directly or indirectly related to climate change. At present, global warming can provide opportunities for aquaculture industrialization of fish or other novel species, with economic implications. However, despite such opportunities, the influx of new species can also cause problems such as ecological disturbances, increase in the reproduction frequency of microalgae such as red tide, increase in disease incidence, and occurrence and periods of high water temperatures in summer. The scale of farmed fish mortality is increasing due to the complex effects of these factors. Increased damages due to fish mortality not only have severe economic impacts on the aquaculture industry, but the social costs of responding to the damage and follow-up measures also increase. various active responses can reduce the mortality damage in fish farms such as improving the management skills in aquaculture, improved species breeding, efficient food management, disease prevention, proactive responses, and system-wide improvements. This review article analyzes the large-scale mortality cases occurring in fish cage farms on the southern coast of Korea and proposes measures to mitigate mortality and enhance responses to such scenarios.