• 한국수산과학회지
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• 제55권3호
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• pp.374-378
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• 2022

The feeding habits of the Glowbelly Acropoma japonicum were examined based on 849 specimens collected from the coastal waters of the South Sea of Korea. The total length (TL) of these specimens ranged from 2.6 to 13.0 cm. A. japonicum fed majorly on Euphausia pacifica (Euphausiacea, % index of relative importance; IRI, 51.9). However with growth, its diet shifted from copepoda to euphausiacea. Overall, as the body size of A. japonicum increased, the mean weight of prey within the stomach (mW/ST) increased.

• 한국수산과학회지
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• 제54권6호
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• pp.1052-1057
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• 2021

The diet composition of common flying squid Todarodes pacificus was studied using 1,084 specimens collected through trawl and jigging from June 2018 to June 2020 in the East Sea of Korea. The mantle length (ML) of the collected individuals ranged from 13.6 to 31.1 cm. Todarodes pacificus is a carnivore. In the study area, T. pacificus was observed feeding mainly on fish and cephalopods, in addition to small quantities of crustaceans. The calculated trophic level value for T. pacificus was 4.10. Small individuals (ML, <18.0 cm) mainly fed on cephalopods, while intermediate (ML, 18.0-23.0 cm) and large (ML, ≥23.0 cm) individuals fed mainly on fish and occasionally on cephalopods. Overall, as the body size of T. pacificus increased, the mean weight of the consumed prey increased (one-way ANOVA, P<0.05).

• 한국수산과학회지
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• 제56권5호
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• pp.728-733
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• 2023

The diet composition of octopus Octopus vulgaris was studied using 392 specimens collected from January to December 2020 in the coastal waters of Yeosu, Korea. The body weight ranged from 86.4 to 3,645.4 g. The most important prey item in the diet of O. vulgaris was decapods, which constituted 43.9% in ranking index (%RI). The second largest prey item was Pisces (%RI=27.9%), and cephalopods (%RI=21.8%) constituted the third largest prey item. The average trophic level of O. vulgaris was 3.97±0.59. Ontogenetic changes were significant among size classes (<400 g, 400-800 g, ≥800 g). The small size class (<400 g) mainly fed on decapods, whereas the medium (400-800 g) and large size (≥800 g) classes mainly fed on cephalopods and Pisces, respectively. The dietary composition varied significantly with season.

• 한국어류학회지
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• 제34권3호
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• pp.179-185
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• 2022

우리나라 서해에서 출현하는 갈치의 식성을 파악하기 위해 4.5~33.7 cm의 항문장 범위를 나타내는 377개체의 위내용물을 분석하였다. 갈치의 주 먹이생물은 74.1%의 상대중요도지수비를 나타낸 어류였고, 멸치가 가장 우점하였다. 이번 연구에서 갈치의 영양단계는 3.84를 나타내었다. 어류는 모든 계절 동안 갈치의 가장 중요한 먹이생물이었으며, 가을철과 겨울철에는 멸치가 우점하였고, 봄철과 여름철에는 참조기가 우점하였다. 어류는 갈치의 모든 크기군(<15 cm, 15~20 cm, 20~25 cm, ≥25 cm)에서 가장 중요한 먹이생물이었으며, 크기가 작은 개체의 경우 샛줄멸과 멸치를 주로 섭식하다 항문장이 커짐에 따라 참조기와 갈치의 섭식 비율이 높아지는 것으로 나타났다. 또한 갈치의 항문장이 커짐에 따라 평균 먹이생물 개체수와 중량이 증가하는 경향을 나타내었다. PERMANOVA 분석을 통해 계절과 크기군에 따라 갈치의 식성은 유의한 차이를 보이는 것으로 나타났다.

• 한국어류학회지
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• 제35권4호
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• pp.354-360
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• 2023

이번 연구에 사용된 꼼치는 2022년 4, 8, 10, 11월에 우리나라 서해에서 저인망으로 채집하였으며, 채집된 꼼치의 전장범위는 3.8~52.2 cm였다. 꼼치의 가장 중요한 먹이생물은 생이하목 새우류였으며, 그중 마루자주새우, 분홍갯가꼬마새우를 주로 섭식했으며, 영양단계는 3.63으로 나타났다. 또한, 꼼치는 생이하목 새우류 중 마루자주새우를 주로 섭식하는 섭식특화종이었다. 크기군별 먹이생물 조성 변화를 분석한 결과, 모든 크기군에서 생이하목 새우류가 가장 우점했으며, 성장함에 따라 마루자주새우의 비율은 감소하는 반면, 분홍갯가꼬마새우의 비율은 증가하는 경향이 관찰되었다. 개체당 평균먹이생물의 개체수는 유의한 차이를 보이지 않은 반면, 중량은 크기군이 증가함에 따라 유의하게 증가하는 경향이 관찰되었다. 계절별 먹이생물 조성 변화를 분석한 결과, 여름과 가을에 생이하목 새우류를 주로 섭식했으며, 생이하목 새우류 중에서 여름에는 마루자주새우, 가을에는 마루자주새우와 분홍갯가꼬마새우를 주로 섭식했다.

• 한국수산과학회지
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• 제44권3호
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• pp.243-250
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• 2011

The effects of food, temperature, salinity, and rearing density on the survival and growth of the swimming crab Portunus trituberculatus, were studied. With regard to food, the larval survival rate to zoea IV was the highest (53.9%) in the mixed feed group (rotifers+ Artemia), followed, in order, by the rotifer, commercial feed, and Artemia groups. The growth of young crabs reared on different diets was the highest in group VI. The survival rate to zoea II at 20 to $30^{\circ}C$ ranged between 77.2% and 83.1%, and was the highest for crab I (17.3%) at $25^{\circ}C$. When young crabs were cultured individually at four different temperatures (20, 25, 30, and $35^{\circ}C$), the growth did not differ significantly at 25 to $30^{\circ}C$, but was higher than at $20^{\circ}C$. The survival rate of larvae to crab I was 12.7 and 11.4% at 25 and 28 psu, respectively, while all of the larvae died at 15 psu. For young crabs, there was no significant difference in growth and survival from 20 to 30 psu. The survival rate decreased with increasing rearing density from zoea I to crab I. Each molting cycle took 1 month from crab I to VIII. Subsequently, the interval increased with growth. The mean body weight of crab XV after 24 months was $428.05{\pm}57.63\;g$.

• 한국해양바이오학회지
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• 제3권1호
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• pp.31-37
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• 2008

Off the 1,572 km long coastline of Namibia lies known as the Benguela upwelling system, a very rich source of marine life supporting traditional and modern forms of fishery. Commercial fishing and fish processing is one of the fastest-growing sectors of the Namibian economy in terms of employment, export earnings, and contribution to GDP. The fishing industry has grown to the extent that it is currently Namibia's second biggest export earner of foreign currency after mining (90% of national output is marketed for export). In 2005, Namibia harvested about 552,164 tonnes of fish. The final value of processed products (export value) that year was around US$ 376.0 million. Besides the marine captured fisheries, Namibia also has a small but vibrant aquaculture sector. Inland captured fisheries exist in the north-east and north-west of Namibia where as commercial freshwater aquaculture of tilapia and catfish is also undertaken. The inland fisheries are mainly subsistence based and typically labour intensive, with low catch per unit effort. However the subsistence fisheries from these regions play a significant role in the lives of rural community. The domestic market for marine fish products is extremely limited due to the small size of the population (2 million). The fishing industry is a source of considerable employment for many Namibians. Huge potential to increase production exists in Namibia, unpolluted high quality marine waters, high natural primary productivity of the seawater, availability of inexpensive fish by-products from established fish processing sector for inclusion in wet aqua-feeds and well-established processing, packaging and marketing systems due to the marine capture fisheries that can be adopted for aquaculture purpose.

• 한국수산과학회지
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• 제49권4호
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• pp.427-435
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• 2016

The effects of salt solution and chlorella on the quality of canned oyster, Crassostrea gigas, were evaluated to obtain basic data regarding the processing of two canned oyster products. In canned oyster processing, the shucked oyster meat was steamed for 20 min and then drained. Then, each can (301-3) was filled with 90 g boiled oyster in 60 mL 1.5% salt solution for the control samples or 30 mL 1.5% salt solution and 30 mL chlorella culture medium for the experimental samples. All canned products were sealed using a vacuum seamer and then sterilized to Fo values of 6-12 min in a steam retort system at 118℃. The viable bacteria count, proximate composition, pH, salinity, yield, volatile basic nitrogen (VBN), amino-nitrogen, thiobarbituric acid (TBA), mineral, color value, free amino acid levels, hardness, and sensory evaluation of the two canned products were measured under various sterilization conditions. There were no significant differences in the physical or chemical factors and little difference in the overall acceptance of the control and experimental samples.

• 한국어병학회지
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• 제23권2호
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• pp.177-187
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• 2010

The Interferon stimulated gene 15 (ISG15) is strongly induced in many cell types by IFNs, viral infections, and double-stranded RNA (poly I:C). The ISG15 homologue cDNA was isolated from the rock bream LPS stimulated leukocyte cDNA library. The rock bream ISG15 homologue was found to consist of 833 bp encoding 157 amino acid residues. Compared with other known ISG15 peptide sequences, the most conserved regions of the rock bream ISG15 peptide were found to be the tandem ubiquitin-like domains and a C-terminal LRLRGG conjugating motif, characteristic of mammalian and non-mammalian ISG15 proteins. Phylogenetic analysis based on the deduced amino acid sequence revealed a homologous relationship between the ISG15 sequence of rock bream and that of Atlantic salmon, Atlantic cod, northern snake head, black rockfish and olive flounder. The expression of the rock bream ISG15 molecule was induced in the peripheral blood leukocytes (PBLs) from 1 to 24 h following poly I:C stimulation, with a peak at 3 h post-stimulation. The rock bream ISG15 gene was predominantly expressed in the PBLs, spleen and gill.

• 한국어류학회지
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• 제32권2호
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• pp.78-83
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• 2020

수온은 양식 대상어의 종자생산에 영향을 미치는 중요한 환경 요인이다. 본 연구는 최근 급격한 자원 감소를 보이고 있는 한해성 어종인 명태의 안정적인 종자생산을 위한 기초자료로 활용하기 위해 수온이 명태의 부화 및 초기 자어 성장에 미치는 영향을 조사하였다. 수정란의 생존율은 5℃가 8℃와 11℃에 비하여 높게 나타났으며, 부화율은 8℃에서 가장 우수하게 나타났다. 그러나 첫 부화, 50% 부화 및 완전 부화까지의 소요 시간은 11℃가 5℃와 8℃에 비하여 빠르게 나타났다. 12주간의 사육기간 동안 자어의 생존율은 5℃가 8℃와 11℃에 비하여 높게 나타났으나, 성장은 11℃가 5℃와 8℃에 비하여 높게 나타났다.