• 한국환경생태학회지
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• 제27권4호
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• pp.429-436
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• 2013

옥정호로 유입되는 37km의 추령천에는 육봉화된 은어의 이동을 가로막는 많은 보가 설치되어 있었으나 2006년 12월 옥정호 추령천 하류에는 은어가 성숙하기 위해 추령천 상류로 이동하도록 어도가 설치되었다. 따라서 2007년 4월부터 10월까지 13개 지점에서 어도와 은어의 성장률을 조사하였다. 그 결과 어도의 설치 후, 치어들은 강수량이 풍부했던 시기에만 소상할 수 있는 상류를 새로 설치된 어도를 통해서 자유롭게 상류로 이동할 수 있었다. 2007년 9월 산란시기 동안 성숙된 은어는 $163{\pm}21.5mm$로 어도가 설치되기 전인 2006년에 비해 약 13mm, 2004년 약 20mm, 2005년 약 57mm정도 더 크게 나타났다. 따라서 하천에서 어도는 육봉형 은어집단의 평균 크기와 생존력에 중요한 역할을 하는 것으로 확인되었다.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2001년도 춘계 수산관련학회 공동학술대회발표요지집
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• pp.99-100
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• 2001

Although cultured sweet smelt production recently have been rapidly increased from 89 metric tons (M/T) in 1997 to 500M/T In 1999 in Korea, wild fish have been still used as broodstock for cultured fish seed. This is considered due to having higher sperm and e99 qualify in wild fish broodstock than cultured fish. However, capturing a number of wild sweet smelt broodstock might lead to decreasing of the production of wild fish, In truth, of which production has been greatly decreased so that a number of artificial juvenile have been stocked some rivers in Korea. (omitted)

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2001년도 춘계 수산관련학회 공동학술대회발표요지집
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• pp.97-98
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• 2001

Alpha-tocopherol (alpha-Toc) is a classical lipophilic antioxidant well known as a scavenger of free radicals in a hydrophobic milieu. The primary function of alpha-Toc is to stabilize cellular and subcellar membrane by preventing peroxidative damage of structural polyunsaturated fatty acids (PUFA). The characteristic aroma of sweet smelt Precoglossun altivelis is known as oxida breakdown products of PUFA ironically. (omitted)

• Fisheries and Aquatic Sciences
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• 제4권4호
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• pp.163-170
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• 2001

The effect of perilla oil added in diet on the biochemical properties of cultured sweet smelt, Plecoglossus altivelis, was investigated. The cultured fish were fed two different diets for 8 weeks; a control diet was a commercial diet, which was low in the content of docosa­hexaenoic acid (DHA, 22: 6n-3) and eicosapentaenoic acid (EPA, 20: 5n-3) less than approximately $2\%$ (CO group) and an experimental diet (PO group) was added perilla oil as a lipid source in the diet of the CO group. The PO group was superior in growth rate and feed efficiency compared with CO group. This trend showed markedly in female of both groups. The fatty acid composition in the muscle of PO group was closely related with those of the diet, while those of CO group were not. For plasma components, total cholesterol (CHOU of PO group was higher than that of CO group. Thiobarbituric acid-reactive substances (TBARS), hydroxyl (OH) radical levels and superoxide dismutase (SOD) activity of plasma were higher in PO group than CO group. The intensity of watermelon-like or cucumber-like aroma was much stronger in PO group with higher level of TBARS and OH radical in plasma compared CO group. Survival rate was also high in PO group with high levels of phagocytic rate, CHOL and SOD activity. These results suggest that perilla oil might be usefulness as a lipid source of the cultured sweet smelt diet, in which result in high quality of the cultured fish.

• Applied Microscopy
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• 제41권1호
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• pp.13-20
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• 2011

바다빙어목(Osmeriformes), 바다빙어과(Osmeridae)에 속하는 빙어(Hypomesus nipponensis)의 성숙란 난막구조를 광학현미경과 전자현미경을 이용하여 관찰하였다. 빙어의 성숙란은 두 개의 난막으로 둘러싸여 있었으며 바깥쪽 난막의 외층은 한 층의 여포세포가 분포하고 있었고 안쪽의 난막 바깥쪽은 호염기성을 나타내는 구조물들이 배열하고 있었다. 난막의 단면을 투과전자현미경으로 관찰한 결과 두 개의 난막 중 바깥쪽 막은 전자밀도가 균일한 한 층으로 되어 있었고 안쪽막은 전자밀도가 높은 6층이 전자밀도가 낮은 5층에 의해서 분리되어 층상구조를 하고 있었다. 주사전자현미경으로 관찰한 결과 바깥쪽 막은 홈들이 관찰되었고 안쪽막 표면은 무정형의 구조물들이 산재하고 있었다. 또한 동물극 쪽에 한 개의 난문이 관찰되었다. 이상과 같이 빙어의 성숙란은 지금까지 보고된 경골어류의 경우 한 개의 난막으로 둘러싸여 있는데 비해서 두 개의 난막으로 둘러싸여 있다는 것은 매우 중요한 빙어의 종특이성을 나타내며 난막의 미세구조적 특징들은 종을 분류하는 데 이용될 수 있다.

• 환경생물
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• 제23권1호
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• pp.89-92
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• 2005

빙어(Hypomesus olidus)를 사용하여 시멘트 농도에 따른 반수치사농도 (LC/sub 50/), 안정농도 (safe concentration) 및 적용계수 (application factors of pollutant)를 조사하였다. 실험어는 평균체장 8.6±1.2cm의 성어를 사용하였으며, 1주일 이상 안정시킨 후에 50L의 FRP 사각수조를 이용하여 시멘트 농도를 0 (대조구), 10, 25, 50, 100, 250, 500 및 1,000ppm로 설정하고 각 실험구에 30마리씩 수용하였다. 시멘트에 대한 빙어의 급성독성은 500ppm 이상의 농도에서 4시간 이내에 전량 폐사하였다. 그리고 시멘트 독성에 대한 반수치사농도(LC/sub 50/)는 48h-LC/sub 50/은 123.03 ppm, 72 h-LC/sub 50/은 91.20 ppm 및 96 h-LC/sub 50/은 58.88 ppm으로 각각 조사되었다. 또한 안정농도는 2.64∼9.14 ppm (평균 5.88 ppm), 적용계수는 0.045∼0.155(평균 0.100)로 각각 조사되었다.

• 한국수산과학회지
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• 제32권6호
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• pp.689-692
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• 1999

양식산 은어의 품질 향상을 위한 연구의 일환으로 섬진강과 밀양강에서 채포된 천연산과 하동과 밀양 소재의 양식장에서 구임한 양식산 은어의 근육 및 난에 대하여 일반성분 조성을 분석, 비교한 결과는 다음과 같다. 천연산 은어 근육의 수분함량은 $76.7\~77.5\%$, 단백질 $18.4\~19.9\%$, 지질 $2.41\~3.47\%$, 회분 $1.04\~1.33\%$으로 산지에 다른 차이가 거의 없었다. 양식산 은어 근육에서 단백질과 회분 함량은 천연산과 유사하였으나, 지질($4.68\~10.1\%$) 및 탄수화물($1.14\~2.82\%$) 함량은 천연산에 비하여 많았으나 수분 함량은 적었으며, 특히 지질 함량은 양식장에 따라 상당한 차이를 나타내었다. 따라서 양식장에 따른 일반성분 조성 차이는 그들의 사료 조성의 차이가 크게 기여한 것으로 볼 수 있었다. 또한 지질 함량은 거의 모든 시료에서 수컷에 비하여 암컷에서 약간 많은 경향을 보였다. 은어난의 일반성분 조성 중 지질, 단백질, 탄수화물 함량은 근육에 비하여 많았으나 수분 함량은 상대적으로 적었으며, 근육의 경우와 달리 산지 및 양식장에 따라 상당한 차이를 나타내었다. 시험된 모든 시료에서 지질과 수분 함량 사이에는 y= -0.2715x+24.903 (r= -0.7253, p<0.001)로 역의 상관관계를 나타내었다.

• Fisheries and Aquatic Sciences
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• 제7권1호
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• pp.1-9
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• 2004

Sweet smelt (Plecoglossus altivelis) were fed four different diets supplemented with either perilla oil $(2.0\%)$ rich in 18:3n-3 (CP), and perilla oil and Enteromorpha compressa meal $(2.0\%)$ (CPA), soybean oil rich in 18:2n-6 (CO), or soybean oil and algal meal (CA) for 4 weeks. The growth performance, fatty acid composition of muscle, plasma lipid peroxidation and blood components of the sweet smelt were then determined. The specific growth rate and feed efficiency in the fish fed the CPA diet were the highest, while the other groups showed similar results. The fatty acid composition of muscle in sweet smelt reflected the dietary lipids; 18:3n-3 was higher in the fish fed the CP and CPA diets, and 18:2n-6 was higher in the fish fed the CO and CA diets. The other fatty acid profiles presented almost no differences with respect to the diet composition. The fish fed the CA, CP and CPA diets contained significantly lower levels of triglyceride, thiobarbituric acid-reactive substances and hydroxyl radical in their plasma than that fed the CO diet. Phagocytic activity was the highest in the fish fed the CPA diet and higher in those of the fish fed the CP and CA diets compared to the CO diet group. The results from this study suggest that a dietary supplement of $2.0\%$ perilla oil together with $2.0\%$ E. compressa meal may improve the growth and health of cultured sweet smelt.

• 한국수산과학회지
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• 제34권4호
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• pp.419-421
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• 2001

Heritability estimations of masu salmon smelt at underyearing of age were described. Masu salmon was taken from aquaculture station of Mori in Japan. After fertilization, the offsprings in each family were reared in separate egg trays and fingerling tanks. The percentage of fish in each tank which smoltified at 11-month old was recorded, and environmental and genetic factors influencing the percentage smoltification were also studied. Percentage of smoltification was not significantly affected by the number of fish held in a tank, or fish density (correlation coefficient 0.10). However, there was a high correlation ($0.821\~0.565$) between smelt percentage and growth related traits of fish in a family. Heritability estimated from total data was $0.47\pm0.13$, when effects of tanks were ignored.

• Asian-Australasian Journal of Animal Sciences
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• 제24권2호
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• pp.264-271
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• 2011

The effect of replacement of fish meal (FM) in diets with sand smelt meal (SSM) on fatty acid composition of carp fry, Cyprinus carpio, was examined. Five isonitrogenous and isoenergetic (38% crude protein, $15.75\;kJ\;g^{-1}$) diets replacing 0, 25, 50, 75, and 100% FM protein by SSM protein were formulated. Each diet was randomly allocated to triplicate groups of fish in aquaria, and each aquarium was stocked with 20 fish (initial average weight of $0.300{\pm}0.65\;g\;fish^{-1}$). Fish were fed twice daily to apparent satiation for 13 weeks. Results indicated that final weight, specific growth rate and feed efficiency ratio of fish fed with different SSM replacement diets did not differ significantly (p>0.05) from fish fed the control diet, except for 100% SSM level. No significant differences were noted among experimental treatments on dry matter, protein, lipid and ash contents of the fish body composition (p>0.05). Fatty acid analysis showed that saturated fatty acids in fish muscle significantly decreased, but monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) did not change with increasing dietary SSM. However, some changes also could be observed for some particular fatty acids in experimental fish. For example, the amounts of 15:0, 17:0, 18:1n-7, 18:2n-6 and 22:5n-3 significantly increased, but 16:0, 18:1n-9, 18:3n-3 and 20:1 n-9 significantly decreased with increasing dietary SSM. Total n-6 PUFA increased with increasing dietary SSM, but total n-3 PUFA were not changed in muscle of fish fed the experimental diets. The ratio of n-3 to n-6 was not affected significantly in muscle of fish fed the experimental diets containing different proportions of SSM, including the control diet.