• 한국환경생물학회:학술대회논문집
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• 한국환경생물학회 2002년도 춘계공동학술대회 및 심포지움 초록집
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• pp.67-67
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• 2002

• 한국동물학회:학술대회논문집
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• 한국동물학회 2001년도 한국생물과학협회 학술발표대회
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• pp.147.1-147
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• 2001

No Abstract, See Full Text

• 생태와환경
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• 제39권2호통권116호
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• pp.245-256
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• 2006

삼각망(fyke net)과 삼중자망(trammel net)의 망목을 달리하여 횡성호에서 2005년 4월부터 10월까지의 기간에 포획된 어류는 총 8과 22종 8,626개체였고, 생체량은 122.9kg이었다. 이중 삼각망에서 8과 21종 8,168개체가 출현하였고 생체량은 96.6kg이었고, 삼중자망에서 6과16종 458개체였고 생체량은 26.3kg이었다 분석결과 삼중자망이 삼각망에 비하여 출현종, 개체수, 그리고 생체량 모두 현저하게 낮았다. 한편 출현종의 수는 망목의 크기가 작아짐에 따라 증가하는 것으로 나타났다. 또한 망목이 작은 삼각망은 작은 치어부터 대형어류까지 모두 채집할 수 있어 그 지역의 세부적인 어류상을 정성적으로 분석하는데 알맞을 것으로 보이고 삼충자망은 적절한 크기의 망목을 사용할 경우 조사지역의 출현종을 파악하는데 매우 효과적인 것으로 나타났다.

• 한국어류학회지
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• 제20권1호
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• pp.45-53
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• 2008

2005년 1월부터 2005년 12월까지 동대만의 잘피밭에서 채집된 돌팍망둑의 식성을 조사하였다. 돌팍망둑의 주요 먹이는 어류 및 새우류였으며, 그 외, 곤쟁이류, 단각류 (옆새우류 및 카프렐라류), 요각류, 두족류, 갯지렁이류 및 게류등이 소량 섭식되었다. 돌팍망둑은 초기에는 요각류와 단각류를 많이 섭식하였으나, 성장함에 따라 어류와 새우류의 섭식율이 점차 증가하였다. 돌팍망둑은 계절에 관계없이 새우류 및 어류를 주로 섭식하였다. 체장별 및 계절별 dietary breadth는 전체적으로 낮게 나타났다.

• 한국어병학회지
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• 제36권2호
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• pp.395-401
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• 2023

Myxosporeans are widespread cnidarian endoparasites in marine and freshwater ecosystems and several species were reported to be a threat to cultured fish causing serious diseases with mass mortality. In the present study, we found a myxosporean species in the genus Thelohanellus from the gills of the cultured common carp (Cyprinus carpio) fingerling for the first time in Korea. The morphological observation showed 500 ㎛ ~ 1 mm size, oval to circular shaped plasmodia containing spores which are pyriform at the anterior end and round at the posterior end (average size 20.1 ㎛ × 9.1 ㎛), with 5 to 6 turns of a single polar filament located in the polar capsule with an average size of 10 ㎛ × 4.6 ㎛. The 18S rRNA sequence was closest to the sequence of T. wangi among Thelohanellus species infecting gills but was not completely identical. Based on the morphological characteristics and molecular analysis results, we classified the present myxosporean parasite as Thelohanellus sp., temporarily. The prevalence and infection intensity of Thelohanellus sp. in the common carp fingerling were very high, which was thought to be the main cause of high mortality.

• 한국수산과학회지
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• 제55권6호
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• pp.894-902
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• 2022

This study investigated the effects of photoperiod (NL 12L:12D and LL 24L:0D) and body sizes (30 g and 50 g) on parr-smolt transformation, post-smolt growth and blood properties in the off-season parr-smolt stage of Atlantic salmon reared in a recirculating aquaculture system (RAS). Potential off-season salmon smolt were reared in a freshwater RAS for 80 days and then all experimental fish were transferred to seawater. In both LL groups (LL-30 and LL-50), we recorded and increase in specific growth rate and reduction in feed conversion, although there were no significant difference in body size. The values of osmolality, and serum Na⁺, Cl^- and cortisol concentrations in the LL groups were maintained at lower levels than in NL group fish, and LL group fish were observed to recover to the pre-seawater adaptation state more rapidly than those in the NL group. ID chips were inserted in all smolts reared in freshwater. These fish were subsequently transferred to full-strength seawater and thereafter individual growth rates were monitored for 120 days. The results indicated that compared with smolt reared under natural photoperiodic condition, 24 h lighting in freshwater contributed to enhancing post-smolt specific growth rate in seawater.

• 한국발생생물학회지:발생과생식
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• 제23권2호
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• pp.183-191
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• 2019

The objective of this study is to evaluate the anesthetic effects of clove oil and tricaine methanesulfonate (MS-222) on the Far Eastern catfish, Silurus asotus, by measuring the times to anesthesia and recovery. Each anesthetic effect of clove oil and MS-222 was tested in two groups of fish with different body sizes: a group of small fish (mean body length: $15.5{\pm}1.58cm$, mean body weight: $50.1{\pm}5.91g$, n=20) and a group of large fish (mean body length: $31.5{\pm}4.19cm$, mean body weight: $302.1{\pm}15.22g$, n=20). The anesthetics were used at concentrations of 200, 300, 400, 500, and 600 ppm. The results showed significant relationships between the concentration of the anesthetic and the body size of the fish. Each of these variables showed statistical significance (p<0.05). The time to anesthesia decreased linearly with increasing concentration in the large fish for both clove oil and MS-222 (p<0.05). Based on an optimal anesthetic time of approximately 1 min, the preferred concentrations of the anesthetics were 500 ppm for clove oil and 600 ppm for MS-222. Both the anesthetic time and the recovery time were shorter for the small fish than for the large fish (p<0.05). Our study showed that the smaller-sized Far Eastern catfish was more easily anesthetized and recovered more rapidly from anesthesia than the larger-sized fish.

• 한국수산과학회지
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• 제46권4호
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• pp.407-412
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• 2013

We performed four sets of feeding trials to establish optimum feed size (Exp-I), stocking density (Exp-II) and feeding frequency (Exp-III and IV) for Korean rockfish. In Exp-I, three different particle sizes of a commercial diet (small, 2.0-2.1 mm; medium, 2.4-3.2 mm; and large, 4.0-5.3 mm) were fed to four replicate groups of fish ($22.8{\pm}0.1g$), each of which was fed to apparent satiation for six weeks. In Exp-II, fish ($44.3{\pm}0.4g$) were reared at four stocking densities (1.5, 3.0, 4.5 and 6.0 $kg/m^3$) and fed a commercial diet to apparent satiation for four weeks. In Exp-III, fish ($14.8{\pm}0.1g$) were fed a commercial diet once, twice, thrice, $4{\times}$ or $5{\times}$ a day at a feeding ratio of 3.25% of body mass. Another group of fish was fed the same commercial diet $5{\times}$ a day to apparent satiation; this treatment was designated FS (five times satiation/day). In Exp-IV, fish ($31.3{\pm}0.1g$) were fed a commercial diet once, twice, thrice or $4{\times}$ a day to apparent satiation. Another group of fish was fed to apparent satiation once every 48 hours. In Exp-I, fish fed the large particle (4.0-5.3 mm) diet had a significantly higher feed conversion ratio and lower protein efficiency ratio than fish fed the small particle diet. In Exp-II, groups of fish reared at densities of 4.5 and 6.0 $kg/m^3$ had significantly higher feed intake and growth performance than fish reared at 1.5 and 3.0 $kg/m^3$. In Exp-III, fish fed to apparent satiation had significantly higher growth performances than fish fed once or $4{\times}$ a day. A significantly higher feed conversion ratio and a lower protein efficiency ratio were obtained in the FS group. In Exp-IV, growth performance and feed utilization efficiency were not significantly affected by experimental variation in feeding frequency. Fish fed to apparent satiation once every 48 hours had better feed utilization than those in other treatments and growth performances of those were comparable. Therefore, the optimum feed particle size, stocking density and feeding frequency for Korean rockfish under conditions we used were 2.0-3.2 mm, 4.5-6.0 $kg/m^3$, and once a day or once every 48 hour, respectively.

• 한국수산과학회지
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• 제46권4호
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• pp.365-370
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• 2013

This study investigated the effect of dietary paprika on the skin coloration of red- and white-colored fancy carp Cyprinus carpio var. koi, in two age groups: 0-age ($7.4{\pm}0.1$ g/fish) and 1-age ($164{\pm}2.9$ g/fish). Three isonitrogenous diets were formulated to contain 0, 5, and 10% paprika (Con, P5 and P10, respectively). Three replicate groups of 0-age fish and two replicate groups of 1-age fish were fed one of the experimental diets for 9 weeks. Survival, weight gain, and feed efficiency were not significantly affected by the dietary paprika level (P>0.05) at both fish sizes. The dietary paprika level influenced the redness ($a^*$), lightness ($L^*$), and yellowness ($b^*$) of fish skin. The $L^*$ value of the skin of the fish fed the P5 and P10 diets tended to decrease with feeding period. The skin $a^*$ value of 0-age fish (small) fed the diets containing paprika increased significantly with feeding period and was higher than that of fish fed the control diet after 3 weeks (P<0.05). However, the $a^*$ value of 1-age fish (large) fed the diets containing paprika tended to increase slightly with feeding period. At the end of the experiment, the skin total carotenoid level was increased significantly in fish of both sizes fed the P5 and P10 diets compared to fish fed the control diet. Therefore, 5% paprika powder in the diet increases the skin redness of red- and white-colored fancy carp, especially in small fish.

• 생명과학회지
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• 제6권1호
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• pp.34-39
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• 1996

해양 다당류인 chitosan과 alginate를 이용해서 캡슐을 제조할 수 있었으며 그 성상을 물고기 알과 같은 형태 즉 인조어란의 성상으로 만들 수 있었다. 캡슐의 크기는 공기 사출기의 유속에 의해 1~5mm로 조절할 수 있었다. 캡슐의 기계적 강도는 chitosan요액의 pH와 이온의 농도에 의해 조절할 수 있었으며 원하는 어란의 기계적 강도를 가진 인조캡슐을 제조할 수 있었다. 이러한 인조어란 대체품의 제조이외에도 타분야인 의약, 산업 및 식품 분야에 이용이 가능한 캡슐로 이용 될 것이다.