• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2001년도 추계 수산관련학회 공동학술대회발표요지집
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• pp.253-254
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• 2001

Aquaculture production of Hounder has been increased in the last decade in Korea. However, moist pellet primarily made of raw fish has been used as feed for flounder. Therefore, for further expansion of flounder farming, it is essential to employ practical formulated feeds which can support reasonable growth. Several studies on nutrition (Lee et al., 2000) and utilization of some plant protein source as a substitute for fish meal (Kikuchi, 1999) have been conducted for flounder diets. (omitted)

• 한국양식학회지
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• 제13권1호
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• pp.13-19
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• 2000

A genetic analysis of reproductive characters of masu salmon at three year classes was described. the reproductive performance of masu salmon spawning at 2 years of age was analyzed using data number fertility hatchability and growth traits to the juvenile stage. The phenotypic correlations among the traits were also estimated. it was determined that egg volume was the principle deter-minant of egg number and that the relationship of number to size was negative. It is recommended that selection for egg size be included in all selection programs and egg number be ignored in any welection program designed to increase body size. Phenotypic correlations between body size of parents and egg traits as well as between body size of offspring and egg traits were not significantly positive or negative magnitude at three year classes.

• Environmental Analysis Health and Toxicology
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• 제25권2호
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• pp.161-168
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• 2010

The observed the toxic effect of WSF (Water Soluble Fraction) on development time, development rate, attachment rate, survival rate and growth of the larva during the early stage of the Pacific oyster, Crassostrea gigas. The time required early juvenile from the fertilized eggs exposed to crude oil (WSF) was about 13 hours in control group. But that of the crude oil dose group takes 12 hours, with shorter compared to control group. Development and attachment rate of the oyster significantly higher in 0.4 and 0.8 mg/L WSF compared to control group (P<0.05) but significantly lower more than 1.6 mg/L WSF (P<0.05). Survival rate of the oyster larva significantly higher in 0.4 and 0.8 mg/L WSF compared to control group (P<0.05) but significantly lower more than 2.4 mg/L WSF (P<0.05). Survival rate of spot showed no significantly difference compared to control group (P>0.05). Shell growth of the oyster were significantly lower more than 1.6 mg/L WSF compared control group (P<0.05). The effect concentration of crude oil showed that more 0.4 mg/L in development and attachment rate and more 1.6 mg/L in growth. Also, chronic exposure of crude oil even effect also in low concentration.

• 한국수산과학회지
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• 제50권3호
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• pp.257-262
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• 2017

This study was conducted to investigate the growth and skin color of red- and white-colored fancy carp Cyprinus carpio var. koi juvenile reared at different water temperatures (21, 24, 27, and $30^{\circ}C$) for eight weeks. Two experimental diets were prepared to contain 10% Arthrospira platensis or 10% Arthrospira pacifica powder. After the feeding trial, survival was 100% in all group. Weight gain of fish reared at 24, 27, and $30^{\circ}C$ was higher than $21^{\circ}C$ group. Feed efficiency was not affected by water temperature and dietary Arthrospira sp. Daily feed intake tended to increase with water temperature. The $a^*$ value of skin coloration was affected by Arthrospira sp., but not by water temperature. Fish fed the diet containing A. pacifica powder reared at $27^{\circ}C$ had the highest $a^*$ value among the groups. Total carotenoids were highest in fish fed the diet containing A. pacifica powder reared at $21^{\circ}C$. Based on the results of this study, we conclude that 24-$30^{\circ}C$ water temperature was the optimal range for growth, and dietary inclusion of A. pacifica improved the skin redness of red- and white-colored fancy carp reared at $27^{\circ}C$.

• 수산해양교육연구
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• 제20권1호
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• pp.90-94
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• 2008

Growth and water quality in Japanese eel, Anguilla japonica ($6.0{\pm}0.9g$) fed extruded and paste type diets were compared for 8 weeks. Fish in the duplicate tanks were fed with one of three experimental diets: two different extruded pellet diets and one paste type diet. Six FRP tanks were used with stocking density of 3.6 kg per tank (3 m3). Restricted feeds (ca. 2% of body weight) were served twice daily. Weight gains were checked at the end of every two-week interval, and water qualities in terms of NH4-N and NO2-N were determined daily one hour after feeding in the morning. Water temperature, dissolved oxygen, and pH were constantly kept within the optimum range, while fifty percent of total water volume was changed daily. Eels fed the extruded pellet diets showed significantly better (P<0.05) growth performance than did eels fed the paste type diet. The amount of feed waste from the paste type diet was significantly greater than those from the extruded pellet diets (P<0.05). Ammonia (NH4-N) waste was significantly higher from the paste diet than from the extruded pellet diets (P<0.05). These results show that extruded pellet diets are better than the paste type diet for growth and water quality management in eel culture.

• 한국어류학회지
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• 제24권1호
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• pp.41-47
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• 2012

본 연구는 조기류(참조기, 수조기)의 양식생물학적 기초자료를 확보하고자 육상수조에서의 성장 특성 및 저수온 노출에 대한 영향을 조사하였다. 1년 사육기간동안 수조기가 참조기에 비해 성장이 빨랐고, CF는 모두 9월에 가장 높게 나타났으며, DFI는 모두 9~10월에 최대값을 보인 후 낮아졌다. 사료계수는 참조기가 2.20, 수조기가 1.34였다. 완만한 수온 하강에 대한 영향은 참조기와 수조기 미성어 모두 $4.7^{\circ}C$ 이하에서 폐사가 발생하였으며, 조기류 월동의 임계수온은 $9^{\circ}C$로 나타났다.

• 한국수산과학회지
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• 제47권6호
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• pp.810-817
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• 2014

Two consecutive feeding trials were conducted to evaluate the effects of extruded pellet (EP) and raw fish-based moist pellet (MP) in the juvenile (experiment I) and sub-adult (experiment II) stages of olive flounder, Paralichthys olivaceus. The fish were distributed randomly to three aquarium tanks, as a group of 1,200 fish (initial mean weight $13.5{\pm}1.76g$) in experiment I, and as a group of 390 fish (initial mean weight $385{\pm}15.3g$) in experiment II. In experiment I, the weight gain, specific growth rate, feed efficiency, protein efficiency ratio, and survival of fish fed EP were all significantly higher than those of fish fed MP. In experiment II, no significant differences were observed in weight gain, specific growth rate and survival between the EP and MP groups. However, the feed efficiency and protein efficiency ratios of fish fed EP were significantly higher than those of fish fed MP. The results of this study indicate that EP could be developed to replace MP for market size production of olive flounder without any adverse effects on the growth performance. The dietary formulation used in this study could be used as an appropriate feed for olive flounder.

• 한국수산과학회지
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• 제40권5호
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• pp.315-322
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• 2007

Kjellmaniella crassifalia Miyabe is one of the valuable seaweed crops cultured in the Korean coastal waters of the East Sea. Unfortunately recent environmental changes have adversely influenced its growth, prompting the need to develop techniques for species restoration. To obtatin biological information, the growth of the species was monitored for one year. The maximum blade length, $110{\pm}45cm$, was attained in July, and zoospores were released in November. The optimum culture conditions allowing juvenile sporophytes to grow to young blades consisted of $20{\mu}mol/m^2s\;at\;10^{\circ}C$ under which the blade length grew to $1,732.5{\pm}143.3{\mu}m$ in 42 days. Sporangial sori started to form in September, reaching 85% maturity in November and 89% maturity in December. Examining the growth of the species according to depth, the individuals growing at 5 meters grew the most, reaching a blade length of $75.9{\pm}18.9cm$ in August.

• 수산해양교육연구
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• 제27권3호
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• pp.718-724
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• 2015

To survey the most feeding frequence of formulated diet as food for cultured puffer in winter season, we performed a rearing test using juveniles of river puffer, Takifugu obscurus (body weight 15.0 g) for 120 days. The feeding frequencies were set up as 2times/1day, 2times/2days, 2times/3days and 2times/4days. We tested triplicately the experiment and investigated survival rate, daily food intake (DFI), feed efficiency (FE), condition factor (CF), daily growth rate (DGR). Consequently, growth was increased following to an increasing of feeding frequency, was the fast in 2times/1day of feeding frequency, and was the slowest in 2times/4days (p<0.05). DFI and CF were increased following to an decreasing of feeding frequency and was the highest in 2times/4days of feeding frequency. FE was decreased following to an decreasing of feeding frequency, and was the highest in 2times/1day of feeding frequency. In a proximate carcass composition at the final day, moisture and crude lipid contents were the lowest in 2times/4days, and in survival, there was not any significant difference among experimental groups. Therefore, we concluded that the 2times/2days are the best of feeding frequency for economical benefit of river puffer culture in winter season.

• Fisheries and Aquatic Sciences
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• 제22권4호
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• pp.8.1-8.9
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• 2019

A 12-week feeding trial was designed to evaluate the effect of total replacement of fish oil (FO) with terrestrial alternative oils on growth, feed utilization, body composition, hematological parameters, and fillet fatty acid profile of mandarin fish juveniles. Four iso-nitrogenous (56% crude protein) and iso-lipidic (13% crude lipid) practical diets were formulated. A control diet contained 6% FO and three other experimental diets were prepared by replacing FO with linseed oil, soybean oil, and lard (designed as FO, LO, SO, and lard, respectively). Each diet was randomly allocated to triplicate groups of 25 fish ($1.8{\pm}0.03g/fish$) in a circular tank. Complete replacement of FO by three tested alternative oils had no remarkable impact on growth performance, feed utilization efficiency, and morphological and hematological parameters of juvenile mandarin fish. However, daily feed intake was found to be significantly higher for fish fed the SO diet compared with those fed the FO and LO diets. Fish fed LO and SO diets exhibited significantly higher levels of the whole body lipid compared to fish fed diet containing FO. Fillet fatty acid composition reflected dietary fatty acid profile. The highest level of ${\alpha}$-linolenic acid, linoleic acid, and oleic acid was observed in fish fillet fed LO, SO, and lard, respectively. Although the eicosapentaenoic acid level of fish fillet fed diet FO was higher than other treatments, no significant difference was found in docosahexaenoic acid content among all dietary groups. The results of the present study clearly demonstrate that the complete replacement of FO in mandarin fish diets is achievable. These findings are useful in dietary formulation to reduce feed costs without compromising mandarin fish growth.