• Fisheries and Aquatic Sciences
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• 제26권9호
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• pp.525-534
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• 2023

Vitamin C plays an important role for fish survival, growth and disease resistance. However, the optimal vitamin C for rearing red drum Sciaenops ocellatus juveniles in Vietnam is not known. To address this issue, a 70-day feeding trial was conducted to evaluate the optimal dietary vitamin C requirements for red drum juveniles. Seven isonitrogenous (55.35% protein) and isolipidic (9.07% lipid) diets were formulated to include graded vitamin C concentrations of 23.2, 124.5, 235.2, 423.8, 626.7, 824.6, and 1,027.3 mg/kg, respectively. The results showed that fish fed on 423.8 mg/kg vitamin C diet had the highest growth rate, which can be linked to the increased feed utilization. Broken-line analysis indicated that the optimal dietary vitamin C requirements of red drum juveniles were 342.92 and 405.80 mg/kg for growth parameters, feed utilization, body composition and biochemical parameters of serum. Based on these parameters the optimal vitamin C supplementation level for red drum juveniles was estimated in the range of 342.92-405.80 mg/kg vitamin C in the diets with direct applications in producing artificial feed for rearing juveniles of this species in Vietnam.

• 한국수산과학회지
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• 제35권3호
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• pp.237-241
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• 2002

This study was performed both to explore the host of nervous necrosis virus (NNV) between mariculturing fish species and to examine the phylogenic position of the NNV in Korea. NNV was confirmed on the basis of histopathological and molecular biological examination, then VNN infection was Preyed from either moribund or dead fishes including red drum, Sciaenops ocellatus; oblong rock fish, Sebastes oblongus and flounder, Paralichthys olivaceus. As a result of sequencing for a part of ms, virus from red drum was showed $98\%, $97\%, $86\% and $74\% homology with oblong rock fish, grouper, Japanese flounder and striped jack, respectively. On the other hand, NNV from oblong rock fish was demonstrated $96\%, $85\% and $72\% homology with grouper, Japanese flounder and striped jack, respectively. NNV from red drum and oblong rock fish was exhibited phylogenically distant from the representative NNV, SJNNV originated from striped jack. On the contrary, the viruses appeared to be similar species with Taiwan NNV isolated from culturing grouper.

• 한국양식학회지
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• 제15권3호
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• pp.131-138
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• 2002

수온과 사육밀도에 따른 홍민어의 성장을 조사하기 위하여 20${\pm}$0.5, 23${\pm}$0.5 그리고 26${\pm}$0.5$^{\circ}C$로 각각 조절한 항온 수조에서 평균전장 4.60${\pm}$0.3 cm, 체중 1.17${\pm}$0.6 g되는 치어를 32주간 비교 사육하였으며, 평균 전장 26.6${\pm}$1.7cm, 체중 213.6${\pm}$46.7 g되는 개체를 대상으로 사육밀도 2.16, 4.24 그리고 6.40 kg BW/㎥로 조절하여 25주 동안 사육하였다. 수온에 따른 성장실험에서 전장, 체중, 일간 성장률에서 26$^{\circ}C$, 23$^{\circ}C$, 20$^{\circ}C$ 순으로 수온이 높을수록 빠른 성장을 하였다. 일간섭식율에서도 26$^{\circ}C$에서 가장 높아 수온이 높을수록 높은 값을 나타내었다(P<0.05). 사육밀도에 따른 성장실험에서 전장, 체중, 일간성장률에서 저밀도 실험구에서 높은 값을 나타내었고 일간섭식율에서도 같은 경향이었으며(P<0.05), 실험 시작시 2.16 kg BW/$m^3$, 4.24 kg BW$m^3$ 그리고 6.40 kg BW$m^3$의 사육밀도는 실험 종료시 각각 7.26 kg BW$m^3$, 14.01 kg BW$m^3$, 19.17kg BW$m^3$로 증가하여 6.40 kg$m^3$에서 생산성이 가장 높았다

• Journal of the Korean Wood Science and Technology
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• 제35권5호
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• pp.38-45
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• 2007

Flakeboards made from ring- and drum-cut flakes of Douglas-fir, hemlock, red lauan and kapur using two kinds of resin levels were evaluated for the selected properties according to flake thickness. The pH and buffering capacity of four species were determined. Those of kapur were extremely different from the other three species. These pH and buffering capacity values result in the poor internal bond strength of kapur flakeboard. The internal bond strength was affected significantly by flake thickness, resin content and species. MOR and MOE in bending strength were maximized at medium drum-cut flake thickness. Screw holding strength was not consistent for flake thickness, but it was influenced by species. Thickness swelling and water absorption of Douglas-fir and hemlock flakeboard were minimized at medium drum-cut flake thickness.

• 한국어병학회지
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• 제14권2호
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• pp.91-95
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• 2001

1999년 10월에서 11월 사이에 남해안 일대의 홍민어 종묘 생산장에서 20~30열령의 치어가 척추만곡 및 이상유영을 하며 대량 폐사하였다. 병어는 특이 외부 증상이 없었고, 높은 누적폐사량이 바이러스 질병으로 의심되어, 조직학적 및 분자생물학적인 검사를 행하여 폐사원인을 확인하였다. 폐사개체의 조직을 H-E 염색하여 관찰한 결과 뇌와 안구의 신경세포에서 공포와 괴사가 관찰되었고, 전자현미경 관찰에서는 안구와 뇌에서 바이러스 입자가 관찰되었다. RT-PCR 결과에서는 ${\fallingdotseq}426$ bp의 DNA 단편을 확인할 수 있었다. 이러한 결과로 홍민어에서 발생한 대량폐사는 바이러스성 신경괴사증(VNN)으로 진단되었다.

• 한국어병학회지
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• 제19권1호
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• pp.65-72
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• 2006

홍민어의 종묘 생산 중에 자어의 대량 폐사를 일으키는 nervous necrosis virus (NNV)의 감염에 의한 피해를 방지하기 위하여 NNV 미감염 친어의 선발에 의한 종묘 생산을 시도함과 동시에 수정란, 부화자어, 먹이생물, 사육 용수 등의 NNV 감염 여부를 확인하였다. RT-PCR법에 의한 홍민어 친어의 바이러스 감염 여부를 확인한 결과, 총 40마리의 검사어 중에서 양성인 개체가 18마리, 음성인 개체는 22마리였다. 시험어로부터 자연 산란된 수정란 및 경과 단계별 부화 자어로부터 PCR법을 이용한 NNV 감염 확인 결과, 미감염 친어로부터의 수정란에서는 바이러스가 확인되지 않았으나, 감염된 친어로부터의 수정란에서는 바이러스 감염이 확인되었다. 또한 자어의 먹이생물인 클로렐라, 로티퍼, 알테미아 및 사육 용수를 대상으로 한 NNV 검출 결과, 모두 음성으로 나타났다. 부화 후 8주간의 감염 및 미감염 자치어의 사육 결과에 있어서는 초기 2주째까지의 생존율이 각각 80%, 85%로서 양호하였으나, 부화 후 25일째부터 폐사가 일어나기 시작하였다. 감염 친어구의 경우 41일째에 100% 폐사한 반면, 미감염 친어구는 최종적으로 18.3%의 생존율을 보여, 이러한 결과는 친어에 대한 NNV 검사를 실시하여 바이러스에 감염되지 않은 홍민어 종묘를 생산할 수 있다는 것을 제시한다.

• Food Science and Biotechnology
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• 제15권4호
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• pp.506-510
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• 2006

To be used as a source of astaxanthin by animals, the red yeast Xanthophyllomyces dendrorhous needs to be dried and the cell wall ruptured. Spray-drying and flat-roller milling successfully prepared the yeast as a feed additive with little loss of astaxanthin. Spray-drying successfully dried the yeast with negligible decomposition of astaxanthin compared to drum-drying. By repeated milling with a flat-roller mill, astaxanthin extracted with ethanol increased from 0.01 to 1.31 mg astaxanthin/g yeast. This method did not decompose astaxanthin in contrast to chemical digestion of the cell wall. Flat-roller milling effectively flattened and cracked the dried cells. Astaxanthin in yeast prepared by spray-drying and flat-roller milling was well absorbed by animals. Specifically, when spray-dried and milled yeast was supplied in the feed (40 mg astaxanthin/kg feed), astaxanthin was successfully absorbed (1,500 ng/mL blood and 1,100 ng/g skin) by laying hens.

• Journal of Biosystems Engineering
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• 제34권3호
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• pp.140-146
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• 2009

The garlic, along with the red pepper, is one of the major seasoning vegetables in Korea. Garlic clove planting is one of the most laborious operations. Labor cost is the main source of high production cost of the garlic. Because of the geometrical uniqueness and irregularity of garlic cloves, mechanization of garlic clove planting is very difficult. To overcome price competition against the imported garlic, however, there has been a need of development of a clove metering device and a planting device for the garlic clove planter. Computer simulation, laboratory tests and field tests were conducted to develop a garlic clove planter. This research was conducted to drop garlic cloves into a soil holes through a drum bucket metering system and a rotary type planting system. Followings are the major achievements from this study. 1. The metering device consisted of a drum, a guide, a bucket and a bucket cover. Opening positions of the metering hopper were evaluated at different positions and trajectories of planting hoppers. The simulation showed that the optimum positions of hopper was -15${\sim}$0 mm in the x direction. 2. When the planter was tested under different soil textures and water contents, the best performances were obtained in a upland field with 29.1% water content and a paddy field with 18.3% water content where single clove metering and missing rate were 88.4% and 1.3%, and 90.7% and 2.0%, respectively.

• 한국조리학회지
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• 제23권2호
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• pp.159-168
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• 2017

본 연구는 도미회의 원료판별 및 도미유사어종간의 품질을 비교하였다. 도미 및 도미유사어종의 일반 성분을 측정한 결과는 다음과 같다. 근육 수분 함량, 단백질 함량 및 지방 함량 K, P, C는 도미의 근육에서 비교적 높은 값을 보였다. Fe는 함량이 낮았다. 중금속 성분을 측정한 결과, 도미와 숭어에서는 Cd가 검출되지 않았다. 붉은 광산에서 $0.01{\pm}0.00mg/kg$이 검출되었다. 다른 중금속은 기준치 이하이거나 검출되지 않았습니다. 전기영동 결과, 붉은 띠무늬의 66~55 kDa에서 나타난다. 도미와 가숭어의 경우, 밴드의 독특한 특징은 보이지 않았습니다. 도미의 경우 유사한 어류와 도미 물고기 사이에 식품 과학에 큰 차이가 없으나, 도미회가 비싼 가격으로 유통되고 있다. 연구 결과를 바탕으로 소비자의 안전한 음식 섭취와 올바른 유통문화 확산이 이뤄지길 바란다. 식품성분 분석 자료의 공유와 구별법을 교육하여 소비자가 원하는 가격으로 식재료를 구입할 수 있는 환경이 조성되어지길 바란다. 나아가 도미 외 타어종의 식품판별과 식품학적 연구가 연구되어지길 바란다.

• 수산해양기술연구
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• 제47권4호
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• pp.300-315
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• 2011

The investigation for the catch and species composition in the deep sea of the East Sea was done to search marine organisms using some kinds of traps with small commercial fishing vessel near Goseong, Korea from 2008 to 2009. The experiments was carried out with some different traps at the depth of 200m, 400m, 700m and 1,000m. In 2008, the amount of catch with rectangular, cone and drum net traps was 91.4kg with twelve trips and the proportion of catch with rectangular and cone traps was high. Dominant species caught were Aniwan whelk (57%), snow crab (12%), hunchback sculpin (7%) and red snow crab (5%). The catch of Aniwan whelk was done well with rectangular and cone traps at the depth of 700-1,000m. Snow crab was mainly caught with rectangular and cone traps at the shallower depth of 200m, while red snow crab caught a lot with cone trap at the deeper depth of 700m. In 2009, the amount of catch with rectangular, cone and round traps was 92.4kg with nine trips. The proportion of catch with round trap was higher than that with cone trap. Dominant species caught were snow crab (67.1%), Aniwan whelk (14.8%) and northern shrimp (9.8%). Snow crab was caught well with round trap at the depth less than 400m.