• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2000년도 춘계수산관련학회 공동학술대회발표요지집
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• pp.271-273
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• 2000

Recently, possibility of low protein diet with high energy level for improvement of fish production has been proposed in several fish species, especially under restricted feeding rate, fish responded better on high energy diet than low energy diet McGoogan and Gatlin (1999) stressed another benefit of low protein diet with high energy for fish production, in terms of reduction of nitrogen waste from fish metabolism However, others reported no effect of high lipid in feed on performance of fish (Jover et al. 1999). This was probably because that energy availability o requirement for fish varied based on fish species, protein content or quality in feed, rearing water temperature condition and feeding ration. (omitted)

• 한국어병학회지
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• 제18권2호
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• pp.147-156
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• 2005

본 연구에서는 주요 어병세균인 Staphylococcus sp., Streptococcus sp., E. tarda 및 V. anguillarum에 대한 30 종의 해조류 추출물의 항균활성을 검색하였다. 그 결과, C. officinalis, D. simplex, G. furcata, G. lanceolata 및 G. turuturu의 경우는 그람 양성균인 Staphylococcus sp.에 대하여, 그리고 S. thunbergii 및 P. morrowii 는 그람 음성균인 E. tarda와 V. anguillarum에 대하여 항균활성을 나타냄을 밝혔다. 그 중, 가장 우수한 항균활성을 나타낸 P. morrowii의 항균활성분획물인 90% MeOH 분획물은 E. tarda의 증식을 매우 효과적으로 저해하며, MIC는 1 mg/ml으로 측정되었다. 뿐만 아니라, 다양한 pH 조건하에서도 항균활성이 유지되었으며 분획물의 주요활성 성분은 할로겐 함유 phenol계 화합물일 것으로 추정된다.

• 한국수산과학회지
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• 제52권5호
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• pp.468-473
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• 2019

A $2{\times}4$ factorial feeding trial was conducted to examine the effect of feed type and feeding frequency on the performance of sub-adult starry flounder Platichthys stellatus. Two feed types, sinking pellets (SP) and floating pellets (FP), were given to 480 fish housed in tanks. Triplicate groups of fish were fed each feed type at one of four feeding frequencies (one meal every two days, one meal per day, two meals per day, and three meals per day) for nine weeks. Weight gain (WG) and specific growth rate (SGR) of fish were affected by feeding frequency. However, WG and SGR were the same in fish fed SP at two and three meals per day; similarly, there was no difference in WG or SGR of fish fed FP at one meal, two meals, or three meals per day. Feed utilization of fish was affected by both feed type and feeding frequency. These findings suggest that two meals per day of the SP or one meal per day of FP are sufficient for optimum growth performance of sub-adult starry flounder.

• 한국수산과학회지
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• 제52권1호
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• pp.49-58
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• 2019

This study was conducted to investigate the effects of different dietary lipid sources on the growth, feed utilization, body composition and tissue fatty acid profile of olive flounder Paralichthys olivaceus. Five isonitrogenous and isocaloric diets were formulated by adding various lipid sources including soybean oil (SO), eicosapentaenoic acid triglyceride (EPATG) and ethyl ester (EPAEE) forms, docosahexaenoic acid triglycerides (DHATG) and a 1:1 blend of soybean oil and DHATG. Triplicate groups of fish ($6.8{\pm}0.01g$) were fed one of the experimental diets to apparent satiation twice daily for 8 weeks. Fish fed the DHATG diet had the highest growth, protein efficiency ratio and feed efficiency values which were significantly higher than those fed the SO and EPAEE diets. Whole body proximate composition and somatic parameters were not influenced by the dietary treatments. Muscle of fish fed with SO diets were rich in 18:1n-9, 18:2n-6 and 18:3n-3, whereas those of fish fed with EPATG, EPAEE and DHATG diets were rich in n-3 highly unsaturated fatty acids (HUFA). These findings indicated that the inclusion of n-3HUFA oils in olive flounder feed could be beneficial for the fish while simultaneously increasing the concentration of beneficial n-3HUFA in fish fillets destined for the human consumer.

• Fisheries and Aquatic Sciences
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• 제22권1호
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• pp.1.1-1.8
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• 2019

Five experimental diets were formulated to evaluate the effects of dietary enzymatically hydrolyzed tuna by-product on growth, non-specific immune responses, and hematology of juvenile rainbow trout (Oncorhynchus mykiss). A basal diet with 50% of fishmeal was used as control (CON) and four other diets replaced 12.5% ($TBB_{12.5}$), 25% ($TBB_{25}$), 37.5% ($TBB_{37.5}$), and 50% ($TBB_{50}$) of fish meal in the CON diet. Juvenile rainbow trout ($4.87{\pm}0.05g$) were randomly distributed into 15 tanks (50 L) and fed 3-4% of wet body weight two times a day. At the end of 7 weeks of feeding trial, weight gain, specific growth rate, feed efficiency, and protein efficiency ratio of fish fed CON diet were significantly higher than those of fish fed $TB_{50}$ diet (P < 0.05). But there were no significant differences among fish fed CON, $TBB_{12.5}$, $TBB_{25}$, and $TBB_{37.5}$ diets (P > 0.05). There were no significant differences in GPT levels among fish fed CON, $TBB_{12.5}$, $TBB_{25}$, and $TBB_{37.5}$ diets. Also, there were no significant differences in lysozyme, superoxide dismutase, glucose, and total protein levels in all experimental diet (P > 0.05). The broken-line analysis indicated that the minimum dietary level of enzymatically hydrolyzed tuna by-product to replace fishmeal could be 29.7% in rainbow trout. These results indicated that the optimum level of dietary enzymatically hydrolyzed tuna by-product could replace greater than 29.7% but less than 37.5% of fishmeal in juvenile rainbow trout diet.

• 한국수산과학회지
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• 제56권4호
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• pp.373-379
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• 2023

The dietary inclusion of black soldier fly larvae meal Hermetia illucens (BSL) for starry flounder Platichthys stellatus was examined in a four-month trial at a Pohang fish farm. Two diets were prepared: a fish meal-based commercial diet (CD) and an experimental diet containing 7% BSL in the CD (BCD). Fish (average weight, 125.2 g) were reared in a square concrete tank (7×7 m) in triplicates. Feed efficiency was significantly higher in fish fed BCD compared to that of the fish fed CD. The DHA/EPA ratio in dorsal muscle was not significantly affected by the fatty acid composition of the experimental diets. Based on the growth performance, the feed cost for producing 1 kg of starry flounder was 1,797 won for CD and 1,814 won for BCD. With government subsidies the feed cost for producing 1 kg of starry flounder was 1,481 won for CD and 1,309 won for BCD. The results indicate that BSL can be included at 7% without adverse effects on growth performance, fillet composition, or feed cost. However, further research is needed to determine the optimum percentage of BSL as a replacement of FM in starry flounder diets.

• Asian-Australasian Journal of Animal Sciences
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• 제21권9호
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• pp.1367-1375
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• 2008

This study was conducted to investigate the effects of phytase in diets containing cottonseed and soybean meal (CS) on growth performance, feed utilization and digestibility of protein and phosphorus in juvenile olive flounder (initial body weight 2.5 g), Paralichthys olivaceus. Four experimental diets replacing 0%, 30%, 30% and 40% fish meal protein with CS in equal proportion were formulated to be isonitrogenous and isocaloric (designated as CS0, CS30, CS30+P, CS40+P, respectively). Phytase of 1,000 FTU/kg was supplemented in diets CS30+P and CS40+P. Three groups of fish (25 fish per group) were fed one of the experimental diets for 10 weeks. No significant differences were observed in growth performance of fish groups except for the CS40+P diet. Apparent digestibility coefficients of protein and phosphorus in fish fed phytase-containing diets were significantly higher than those of fish fed the CS0 diet. Serum cholesterol was significantly reduced in fish fed the CS-containing diets. Antioxidant activities in the diets and liver of fish were significantly increased with the increment of dietary CS. Gossypol was only detected and found in liver of the fish fed the CS-containing diets. The findings suggest that supplementation of microbial phytase could improve the apparent digestibility of protein and phosphorus in juvenile olive flounder fed the CS-containing diets.

• 한국수산과학회지
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• 제49권5호
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• pp.683-688
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• 2016

The effects of dietary supplementing natural additives [yacon (YC), ginger (GG), and blueberry (BB)] on growth, feed utilization, and body composition of juvenile rockfish were compared to those of ethoxyquin (EQ), which is commonly used to prevent rancidity of fish feed. A total of 480 fish were distributed randomly into 12 50-L flow-through tanks (40 fish/tank). Four experimental diets were prepared: the control diet (Con) with 0.01% EQ, and the YC, GG and BB diets containing 1% YC, GG, and BB instead of wheat flour. Each diet was assigned randomly to triplicate tanks of fish, which were hand fed to satiation twice daily for 8 weeks. Weight gain of fish fed the YC diet was higher than that of fish fed all other diets. Feed efficiency (FE), protein efficiency ratio (PER), and protein retention (PR) in fish fed the YC diet were higher than those in fish fed the other diets. Whole-body chemical composition of the fish was affected by the additive sources. In conclusion, dietary supplementation with GG effectively improved weight gain and feed utilization (FE, PER, and PR) of juvenile rockfish.

• 한국양식학회지
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• 제9권3호
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• pp.247-254
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• 1996

조피볼락 배합 사료로써 dry pellet (DP)의 사용 가능성을 조사하기 위하여, 2회에 걸쳐 사육 실험을 실시하였다. 두 실험에 사용된 사료 조성은 단백질원으로 북양어분이 $56\%$ 첨가된 사료(실험1)와 경제적인 측면을 고려하여 북양어분을 $38\%$로 줄이는 대신, 대두박과 콘글루텐 밀을 $25\%$ 첨가한 사료(실험 2)를 설계하여 각각 DP 및 moist pellet (MP) 형태로 제조하였고, 양어가들이 주로 사용하고 있는 생사료(법동 메가리)와 시판 분말 사료를 1 : 1로 혼합한 생사료 MP(raw h-based MP : RMP)를 제조하였다. 4.7 g 전후의 치어를 11주간 3반복으로 사육한 실험 1의 결과, 최종적으로 평균체중 및 일일 증체율이 DP, MP 및 RMP 사료간에서 서로 유의차가 없었으며, 전어체의 단백질, 지질 및 수분 함량도 사료간에 차이가 없었다(P>0.05). 사료효율은 세 실험구 중에서 RMP구가 가장 높았고(P<0.05), 사료 조성비가 같은 DP와 MP사이에서는 유의차가 없었다. 11 g 전후의 조피볼락을 8주간 사육한 실험 2에서는 성장 및 일일증체율이 RMP 실험구가 DP 실험구보다 좋았지만, MP와 RMP 실험구간에서는 유의한 성장차이가 없었다(P>0.05), 사료효율은 DP구가 가장 낮고 RMP구가 가장 높은 결과를 보였다(P<0.05). 이러한 차이는 사료 단백원 중 식물성 대체 단백원(대두박, 콘글루텐 밀)이 차지하는 비율과 RMP구의 단백질 함량이 $57\%$로 타 실험구보다 높았기 때문인 것으로 판단된다. 실험 1과 2의 결과들로부터 실험 배합 사료의 물성은 조피볼락의 성장이나 사료효율에 큰 영향을 미치지 않을 것으로 보여, 보다 적합한 실용배합 사료가 개발되면, DP도 조피볼락의 배합사료로써 손색이 없을 것으로 전망된다.

• 한국양식학회지
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• 제12권2호
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• pp.123-135
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• 1999

In order to investigate the effect of salinity on growth and osmoregulation of the sweetfish, Plecoglossus altivelis, the fish (post-larva, juvenile, adult) reared in seawater were directly transferred into the experimental rearing water of the different salinities (post-larva : $0\textperthousand$, $5\textperthousand$, $10\textperthousand$, $15\textperthousand$, $20\textperthousand$, $30\textperthousand$. juvenile : $0\textperthousand$, $\10textperthousand$, $20\textperthousand$, $30\textperthousand$. adult : $0\textperthousand$, $15\textperthousand$, $35\textperthousand$, respectively). Fish samples were taken in time courses after transfer for blood and body fluid collection. The changes of sodium, potassium concentration and osmolality of the body fluid and plasma, muscle water content, gonadosomatic index (GSI) and hepatosomatic index (HSI) in the experimental fish were observed in time courses. Growth rate of the post-larva in $\5~25\textperthousand$ were faster than in $0\textperthousand$ (P<0.05). Survival rate was very low in $0\textperthousand$ (P<0.05). No fish survived more than 50 days after transferred into $0\textperthousand$. The concentration of sodium, potassium and osmolality in body fluid of the juvenile sweetfish were slightly decreased at 0.25 day after the beginning of the maintainable level of sodium, potassium and osmolality were $36.4\pm6.2 mM/\ell, 47.5\pm0.7 mM/\ell, 366.3\pm19.1 mOsm/kg, respectively. Except potassium concetration, fish in $0\textperthousand$ and $10\textperthousand$ displayed the pattern of hypoosmotic regulation. Growth rate and survival rate of juveniles of $30\textperthousand$ are significantly low than other groups (P＜0.05). The concentration of sodium, potassium and osmolality in plasma of adult sweetfish were slightly decreased at 1 day after the beginning of the maintainable level of sodium, potassium and osmolality were $159.0\pm2.5 mM/\ell, 5.8\pm0.9 mM/\ell, 338.1$\pm13.3 mOsm/kg respectively. Compared with these values, fish in $0\textperthousand$ and $15\textperthousand$ displayed hypoosmotic regultion. Growth and survival rate of adult in $35\textperthousand$ are significantly low than other experimental groups. GSI was the highest in $15\textperthousand$ after 60 days. HSI was the lowest in $35\textperthousand$. With decreased salinities, oxygen consumption was found to be decreased in the other experimental groups compared to the more than $30\textperthousand$.