• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.50 no.1
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• pp.58-66
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• 2014

The purpose of the study is to estimate the Green-House-Gas (GHG) emissions from domestic eel farm in the water recirculation system or still-water system by the assessment of energy consumptions and GHG emissions for establishing to reduce standards of GHG from a sustainable perspective. GHG emission components as seeds, feed, fuel, electricity, fixed capital, fish respiration, and others were analysed at the different culture type between water recirculation system and still-water system by 3 stage farm size of small, medium, large scale. The result showed that the mean GHG emission of the eel farm was $18.7kg{\cdot}CO_2$ in the stage of production per fish 1kg at different culture type and farm size. Therefore it could be useful for policy, planning, and regulation of aquaculture development with establishing GHG reduction standards.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.5
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• pp.668-675
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• 2021

The infection status of domestic farmed eels Anguilla japonica, Anguilla bicolor and Anguilla marmorata with Japanese eel endothelial cell-infecting virus (JEECV) and anguillid herpesvirus 1 (AnHV) was examined at the major eel farming areas in Korea. These viruses were detected in all areas examined, regardless of the eel species or age. Any farm with a history of viral infection in adult fish confirmed the infection to be transmitted to stocked fry within 3 to 5 months. It is proposed that both viruses are horizontally transmitted within a given farm. The primary symptoms and histopathological lesions produced by the two viral infections are similar, making it difficult to distinguish the two diseases through clinical symptoms. Both viruses displayed 100% detection in the gills, suggesting that the gills are an optimal tissue for JEECV and AnHV monitoring. This study concluded that JEECV and AnHV were prevalent on eel farms across the country and caused very high mortality when the two viruses co-infected fry. Additional studies, including experimental infections, are needed to clearly understand the pathogenicity of each virus and the risk of co-infection.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.3
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• pp.237-242
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• 2011

To evaluate the proximate composition and main nutritive ingredients (vitamin A, $V_A$; vitamin E, $V_E$; cholesterol; the composition of fatty acids) between eels cultured in different domestic eel farms, we analyzed edible parts of eels that were cultured in three "Water Recirculation System (WRS)" farms and three "Still-Water System (SWS)" farms. We found differences in crude protein, crude lipids and the ash content of eel meat between the farms, but water content showed no significant difference. $V_A$ and $V_E$ contents did not show meaningful differences between the two culture methods, but there was a noticeable distinction between the eel farms. In particular, $V_E$ content showed significant differences between the eels of each farm (highest farm, about 25 mg/100 g dry wt; lowest farm, about 1 mg/100 g dry wt). The fatty acids of cultured eels were composed of monoenes (MUFA, 55-60%), saturates (SFA, 30-33%), $\omega$-6 highly unsaturates (HUFA, 1.6-2%) and $\omega$-3 HUFA (8-9.2%). The MUFA content of WRS eels ($59.9{\pm}1.97%$) was higher than that of SWS eels ($55.8{\pm}0.48%$). The contents of other fatty acids were higher in SWS eels (SFA, $33.0{\pm}0.52%$; $\omega$-6FUFA, $1.98{\pm}0.2%$; $\omega$-3 HUFA, $9.2{\pm}0.67%$) than in WRS eels (SFA, $30.5{\pm}1.34%$; $\omega$-6 HUFA, $1.62{\pm}0.19%$; $\omega$-3 HUFA, $8.0{\pm}0.5%$).

• Fisheries and Aquatic Sciences
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• v.16 no.2
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• pp.85-92
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• 2013

To determine the relative importance of two main factors, diet or culture environment, that affect the proximate composition and main nutritive ingredients (vitamin A, vitamin E, cholesterol, fatty acid composition) in cultured eels, we analyzed the composition of eels fed diets of formula feed (FF) produced by four different companies and of eels cultured at five different eel farms that provided only one of the four different FFs. The four commercial eel FFs did not markedly differ in proximate composition or major nutritive compounds, and consequently, these variables did not significantly differ in cultured eels fed the different FFs. The FF imported from Japan was marginally superior to the two domestic commercial FFs and the FF imported from Taiwan in terms of the proximate composition and main nutritive ingredients of both the FF itself and the eels cultured on it. However, proximate composition and main nutritive ingredients significantly differed among eels cultured at the five farms that used a different FF and among eels fed the four different FFs at the same farm. In conclusion, the difference in quality between domestic and Japanese FFs in terms of eel culture was small, whereas physical or chemical environmental differences among farms during eel culture may more strongly affect the proximate composition and levels of the main nutritive ingredients in cultured eels.