• Ocean Science Journal
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• 제40권3호
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• pp.167-176
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• 2005

A time-series sediment trap was deployed at 1,034 m water depth in the eastern Bransfield Strait for a complete year from December 25, 1998 to December 24, 1999. About 99% of total mass flux was trapped during an austral summer, showing distinct seasonal variation. Biogenic particles (biogenic opal, particulate organic carbon, and calcium carbonate) account for about two thirds of annual total mass flux $(49.2\;g\;m^{-2})$, among which biogenic opal flux is the most dominant (42% of the total flux). A positive relationship (except January) between biogenic opal and total organic carbon fluxes suggests that these two variables were coupled, due to the surface-water production (mainly diatoms). The relatively low $\delta^{13}C$ values of settling particles result from effects on C-fixation processes at low temperature and the high $CO_2$ availability to phytoplankton. The correspondingly low $\delta^{l5}N$ values are due to intense and steady input of nitrates into surface waters, reflecting an unlikely nitrate isotope fractionation by degree of surface-water production. The $\delta^{l5}N$ and $\delta^{l3}C$ values of sinking particles increased from the beginning to the end of a presumed phytoplankton bloom, except for anomalous $\delta^{l5}N$ values. Krill and the zooplankton fecal pellets, the most important carriers of sinking particles, may have contributed gradually to the increasing $\delta^{l3}C$ values towards the unproductive period through the biomodification of the $\delta^{l3}C$ values in the food web, respiring preferentially and selectively $^{12}C$ atoms. Correspondingly, the increasing $\delta^{l5}N$ values in the intermediate-water trap are likely associated with a switch in source from diatom aggregates to some remains of zooplankton, because organic matter dominated by diatom may be more liable and prone to remineralization, leading to greater isotopic alteration. In particular, the tendency for abnormally high $\delta^{l5}N$ values in February seems to be enigmatic. A specific species dominancy during the production may be suggested as a possible and speculative reason.

• 한국수산과학회지
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• 제44권2호
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• pp.141-148
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• 2011

This feeding experiment was conducted to investigate the effects of dietary inclusion of various additives on growth performance, hematological parameters, fatty acid composition, gene expression and histopathological changes in juvenile olive flounder (Paralichthys olivaceus). Eleven isonitrogenous (49% crude protein) and isolipidic (10% crude lipid) experimental diets were formulated: no additives (Con); 5% kelp meal (Ke); 10% krill meal (Kr); 1% garlic powder (Ga); 1% citrus meal (Ci); 3% onion powder (On); 1% ginger powder (Gi); 1% mugwort powder (Mu); 1% licorice powder (Li); 1% wasabi powder (Wa); and a mixture (Mix) of these additives. Three replicate groups of juvenile flounder (average weight of 8.5 g) were fed one of the experimental diets to visual satiety twice a day for 15 weeks. The dietary inclusion of additives did not affect survival, weight gain, specific growth rate feed efficiency, daily feed intake, daily protein intake, protein efficiency ratio, hepatosomatic index and visceralsomatic index of the fish. Plasma triglyceride levels were significantly lower in fish fed the Ke, Ga, On, Gi, Mu, Li, and Mix diets than in fish fed the control diet. Plasma glucose, glutamic oxaloacetic transaminase and total cholesterol did not differ among dietary treatments. No significant difference was observed in fatty acid composition and lipid content of the dorsal muscle in fish fed the experimental diets. Myosin gene expression did not differ significantly among treatments after 5 weeks but was significantly lower in fish fed the Kr, Ci, Li, and Mix diets than in control group after 15 weeks. Histopathological analysis showed mild gill hyperplasia and mild necrosis of liver parenchymal cells in several individuals of each experimental group. These conditions were also observed in the control group and were not thought to be related to the inclusion of feed additives. The present findings indicate that the dietary inclusion of additives did not affect growth performance, fatty acid composition, gene expression, and histopathological changes in juvenile flounder. However, plasma triglyceride content may be reduced by supplementation with 5% kelp meal, 3% onion powder, 1% garlic powder, 1% ginger powder, 1% mugwort powder, and the additive mixture.

• 한국양식학회지
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• 제10권1호
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• pp.87-95
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• 1997

단백질원을 달리하여 자체 제조한 실험 사료 K 하(1)과 K 하(2)를 평가하기 위해 국내 양식 현장에서 많이 이용되고 있는 일본산 D사와 H사 제품(D 와 H 사료)을 공급했을 때 자, 치어의 체장, 체중, 그리고 어체의 일반 조성과 지방산 조성 등에 미치는 영향을 조사하였다. 주 단백질원으로 실험 미립자 사료 K 하(1)은 넙치 근육, 혈분, 오징어 분말, 클로렐라 분말, 효모 등을, K 하(2)는 계란 단백, 크릴분, 바지락분, 오징어분, 생효모, 효모 추출물, 카제인 등을 사용하여 제조하였다. 부화 후 40일째까지는 체중, 체장 그리고 생존율에 있어 실험구간에 유의적인 차이가 없었다. 부화 후 83일째의 생존율에 있어서는 D 사료구가 K 하(2) 사료구보다는 유의적으로 높았지만, H와 K 하(1) 사료구와는 유의적인 차이가 없었다. 체중에 있어서는 D 사료가 K 하(1) 사료와 K 하(2) 사료보다 유의적으로 높았지만 H 사료와는 유의적인 차이가 없었다. 체장과 비만도(Condition factor)에 있어서는 부화 후 83일째에 실험사료구간에 유의적인 차이가 없었다. 이와같은 결과는 넙치 자, 치어용 국산 미립자 사료 개발에 대한 가능성을 보여주고 있다.

• 한국식품위생안전성학회지
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• 제38권6호
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• pp.496-507
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• 2023

본 연구는 대한민국 온라인 시장에서 판매되는 48개의 새우 제품의 종판별 및 제품 표시 사항 일치 여부를 조사하였다. 사용 원재료의 종 판별을 위해 cytochrome c oxidase subunit I 유전자의 염기서열을 분석하여 NCBI GenBank 및 BOLD system 데이터베이스에 등록된 생물종의 염기서열과 비교하였다. 또한 계통분석을 수행하여 동정된 새우종을 추가로 검증했다. 종판별 결과 총 16종[흰다리새우(Penaeus vannamei, Whiteleg shrimp or Pacific white shrimp), 북쪽분홍새우(Pandalus borealis, Alaskan pink shrimp), 그라비새우(Palaemon gravieri, Chinese ditch prawn), 돗대기새우(Leptochela gracilis, Lesser glass shrimp), 얼룩새우(Penaeus monodon, Giant tiger prawn), 아르헨티나붉은새우(Pleoticus muelleri, Argentine red shrimp), 산모양깔깔새우(Metapenaeopsis dalei, Kishi velvet shrimp), 태평양난바다곤쟁이(Euphausia pacifica, Isada krill), 가시배새우(Lebbeus groenlandicus, Spiny lebbeid), 꽃새우(Trachypenaeus curvirostris, Southern rough shrimp), 진흙새우(Argis lar, Kuro shrimp), 가시발새우(Metanephrops thomsoni, Red-banded lobster), 깔깔새우(Metapenaeopsis barbata, Whiskered velvet shrimp), 긴발딱총새우(Alpheus japonicus, Japanese snapping shrimp), 대하(Penaeus chinensis, Fleshy prawn), 긴뿔민새우(Mierspenaeopsis hardwickii, Spear shrimp)]이 확인되었으며, 흰다리새우(n=22, 45.8%)가 가장 큰 비중을 차지하였다. 일반명 '새우'를 포함하는 35개 제품(72.9%)에서 표시사항과 불일치를 나타내었으며, 일반명(n=30)을 제외할 경우 불일치율은 10.4%로 낮아졌다. 가공 정도별 불일치율은 다중 가공 제품(n=25, 89.3%)이 단순 가공 제품(n=10, 50%)보다 높은 비율을 보였다. 원산지별 분석 결과 특정 국가와 불일치율과의 상관성은 확인할 수 없었다. 본 연구 결과는 향후 새우 제품의 모니터링 수행 및 새우의 국명 표시 개선을 위한 기초자료로 쓰일 수 있을 것이다.