• Food Science and Preservation
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• v.18 no.5
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• pp.729-738
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• 2011

This study was conducted to investigate the effect of extruded pellets (EP) containing different levels of protein (51%-55%) and lipid (9%-15%) on flesh quality of flounder (Paralichthys olivaceus) comparing with raw fish-based moist pellet (MP). Two replicate groups of 40 fish per each tank (initial mean weight 106 g) were fed one of three experimental EP (EP1, EP2 and EP3) containing different protein and lipid levels, a commercial EP (EP4) and MP for 16 weeks. Moisture content of fish fed MP was significantly higher than that of fish fed all EP. Significantly higher contents of 16:1n-7, 20:4n-6, 20:5n-3 and lower 18:2n-6 were observed in fish fed EP4 and MP compared with fish fed EP1, EP2, EP3. The 22:6n-3 content was not significantly different among all groups. Taurine content of fish fed MP was significantly higher than that of fish fed all EP. Asparagine content of fish fed EP1 was significantly higher than that of fish fed EP2, EP, EP4 and MP. Significant difference were observed in lysine and serine contents of fish fed experimental diets. In nucleotides and their related compounds, ATP and AMP content was not affected by diets. Significant difference were observed in IMP contents of fish fed experimental diets. Textural properties, no significant difference was observed among the fish groups fed different diets.

• Journal of Aquaculture
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• v.18 no.4
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• pp.225-230
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• 2005

This experiment was conducted to compare the effects of extruded pellets and raw fish-based pellet on olive flounder Paralichthys. olivaceus. Six diets were prepared for this study: two formulated extruded pellets (FEP1 & FEP2), three commercially available extruded pellets (CEP1, CEP2 & CEP3) and moist pellet (MP). Weight gain offish fed FEP1 and CEP3 were significantly higher (P<0.05) than those of fish fed FEP2, CEP1, CEP2 and MP, while that of fish fed MP was not significantly different (f<0.05) from those of fish fed the FEP2, CEP1 and CEP2. Feed efficiency of fish fed CEP2 was significantly lower (P<0.05) than those of fish fed FEP1, FEP2, CEP1, CEP3 and MP. There was no significant difference in protein efficiency ratio and hepatosomatic index between fish fed FEP1 and CEP3, and among fish fed FEP2, CEP1 and CEP2. There was no significant difference in condition factor among fish fed the FEP1 and CEP3, and between fish fed FEP2, CTP1 and MP. However, fish fed MP had a lower survival rate than fish fed the other five EP These results suggest that diet FEPl could be developed to replace MP for the owing stage of flounder without adverse effects on growth performance.

• Journal of Aquaculture
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• v.20 no.2
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• pp.114-120
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• 2007

Two feeding experiments were conducted to evaluate the effects of the experimental extruded pellet (EP), commercial EP and raw fish-based moist pellet (MP) on growth of growing flounder (Paralichthys olivaceus). In experiment 1, two replicate groups of the fish (average body weight of $115{\pm}3.2\;g$) were fed one of five experimental diets (EP1-EP5) and MP in circular concrete tanks (4.6 m $\phi$, 0.6 m depth) for 78 days. In experiment 2, in order to evaluate EP in the commercial scale ($8\;m\;{\times}\;8\;m$), flounder (average body weight of $137{\pm}11.4\;g$) were fed one of five EPs (EP1-EP5) used in experiment 1, commercial EP (EP6) and two MEPs (MEP4 and MEP6) as moist pellet types which were made from EP4 and EP6, respectively, by being sprayed with a mixture of water and additives for 80 days. In experiment 1, weight gain of fish fed the all EPs was not significantly different from that of MP. Feed efficiency of fish fed the EP4 was highest, and protein efficiency ratio of fish fed the EP4 and EP5 was significantly higher than that of fish fed the MP (P<0.05). Significant differences were observed in the contents of moisture and crude lipid in the muscle, and moisture in the liver of fish (P<0.05). In experiment 2, weight gain of fish fed the EP4 and MEP4 were highest and feed efficiency showed high tendency in EP4, MEP4 and MEP6. Fish fed the MEP6 showed higher weight gain and feed efficiency compared to those of fish fed the EP6, but there was no difference in those of fish fed EP4 and MEP4. Based on the results of this study, dietary formulations used in EPs could be most recommendable applied in the practical extruded pellet feeds for flounder grown from 114 g to 350 g.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.5
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• pp.533-540
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• 2022

We evaluated a worm-based extruded pellet diet with black soldier fly Hermetia illucens larvae (BSF) meal and BSF oil for olive flounder Paralichthys olivaceus through field feeding experiments at a commercial aquafarm. We prepared two experimental diets by replacing fish meal and fish oil with BSF meal and BSF oil (BEP-1, BSF meal 7%, BSF oil 1%) and (BEP-2, BSF oil 2%), respectively. We prepared raw-fish based moist pellets (MP) for comparison between the two experimental diets. We distributed the olive flounder (220±6.29 g) in square (10 m×10 m×1 m) concrete, 100 ton tanks at a density of 1,600 fish per tank (n=3) in triplicate for each dietary treatment. We fed the diets to the fish to apparent satiation for 7 months. At the end of the feeding trial, we found no substantial differences between the groups in terms of growth performance, survival, or feed utilization. None of the diet groups showed any changes in either hematological or non-specific immune responses. The histological observation of the intestine showed that the goblet cell number and cholecystokinin-producing cell activity increased in the fish fed the BEP diet compared with the those of the fish fed the MP diet. These results indicated that dietary BSF meal and oil can be used for olive flounder without compromising growth or, hematological and histological parameters.

• Journal of Aquaculture
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• v.18 no.1
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• pp.26-30
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• 2005

A 10-week feeding trial was conducted to determine the optimum feeding rate of two extruded pellets (EP1 and EP2) and raw fish-based moist pellet (MP) for juvenile flounder. Two replicate groups of the fish (average weight of 27 g) were fed EP and MP three times daily at different feeding rate (satiation and $85\%$ satiation). Weight gain of fish was not affected by diet, but affected by feeding rate. Weight gain with satiation feeding group showed :t tendency to higher compared to that of fish with $85\%$ satiation feeding at the same diet. Feed efficiency of fish was affected by diet, but not feeding rate. Feed efficiency of fish fed the EP1 and EP2 was higher than that of fish fed the MP at the same feeding rate. Daily feed intake was affected by diet and feeding rate. Daily feed intake of fish fed with satiation was higher than that of fish with $85\%$ satiation at same diet, and this variable of fish fed the MP was higher than that of fish fed the EP 1 and EP2. Protein efficiency ratio of fish fed the MP was significantly lower than that of fish fed the EP1 and EP2 regardless of feeding rate. Lipid content of whole body was affected by diet, and that of fish fed the EP2 and MP at satiation feeding was the highest. It can be concluded that satiation feeding will be good and EP is better than MP for growth of juvenile flounder grown from 27 g to 51 g.

• Fisheries and Aquatic Sciences
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• v.5 no.3
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• pp.229-234
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• 2002

Possibility of raising sunshine bass during the winter season in Korea was investigated. Also, the effect of feed on growth and body composition of sunshine bass was compared at the various salinity. Twenty sunshine bass $(Mean\;weight\;\pm S.D.\: :\;53.9 \pm 0.24 g)$ were stocked into the eighteen circular flow-through tanks. A 2 (feed) $\times$ 3 (salinity) factorial design with triplicate was used for this study. Feed was prepared into the 2 groups: the raw fish-based me>ist pellet (MP) containing $59.5\%$ crude protein and $9.4\%$ crude lipid, and commercial sinking red sea bream feed (CF) containing $49.9\%$ crude protein and $9.4\%$ crude lipid, respectively. And salinity was prepared into the 3 groups: freshwater $(0\%)$, brackishwater $(15\%)$, and seawater $(32\%)$. Fish were fed to satiation twice daily for 6 days a week. Fish were all survived at the end of the 8-week feeding trial. Weight gain (WG) and specific growth rate (SGR) of sunshine bass were significantly (P<0.05) affected by both feed and salinity. WG and SGR of sunshine bass fed the MP were significantly (P<0.05) higher than those of fish fed the CF in the same salinity. Amount of dry feed fed was significantly (P<0.05) affected by both feed and salinity. Feed consumption by sunshine bass fed on the MP was significantly (P<0,05) higher than by fish fed on the CF in the same salinity. Feed efficiency ratio (FER) was significantly (P<0,05) affected by salinity, but not by feed. Protein efficiency ratio (PER) was significantly (P<0.05) affected by both feed and salinity. Moisture and protein content of the whole-body of fish was not significantly (P>0.05) affected by either feed or salinity. However, lipid and ash content of the whole-body of fish was significantly (P<0.05) affected by salinity, but not by feed. In conclusion, the MP was superior to CF for growth of sunshine bass during the winter season in Korea and no mortality occurred. And sunshine bass seemed to grow better in freshwater $(0\%)$ and brac-kishwater $(15\%)$ than seawater $(32\%)$ under these experimental conditions, in terms of improvement in FER and PER in freshwater or brackishwater.

• Journal of Aquaculture
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• v.19 no.3
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• pp.173-177
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• 2006

This study was conducted to evaluate extruded pellets (EP) for growth of adult flounder by comparing with raw fish-based moist pellet (MP). Two replicate groups of 150 fish per each tank (initial mean weight 329 g) were fed one of seven EP (EP1, EP2, EP3, EP4, EP5, EP6 and EP7) and a MP for 8 months. Survival of fish fed the MP was not significantly different from that of fish fed the EP1, EP5 and EP7, but significantly higher than that of fish fed the EP2, EP3, EP4 and EP6 (P<0.05). Weight gain of fish fed the MP was significantly lower than that of fish fed the EPI (P<0.05), but not significantly different from that of fish fed EP2, EP3, EP4, EP5, EP6 and EP7. Feed efficiency of fish fed the MP was significantly lower than EP1, EP3, EP4, EP5 and EP6 (P<0.05), but not significantly different from that of fish fed EP2 and EP7 Feed supply (kg/tank) of fish fed the MP was significantly higher than that of fish fed all EP (P<0.05). Condition factor of fish fed the MP was not significantly different from that of fish fed all EP. The contents of moisture, crude protein and lipid in dorsal muscle and whole body was not significantly different among the groups. It is concluded that the dietary formulation used in the EP1, EP3, TP4, EP5 and EP6 can be applied in the practical extruded pellet feeds for adult flounder (329-680g).

• Journal of Aquaculture
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• v.9 no.3
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• pp.255-264
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• 1996

A 15-week growth trial was conducted to evaluate the economical feed formulations for Korean rockfish (Sebastes sehlegeli). Three replicate groups of fish averaging 33 g were fed one of 8 isoproteic ($49\%$) and isolipidic ($8\%$) diets containing various practical ingredients such as fish meal, meat meal, feather meal, blood meal, soybean meal, corn gluten meal, and wheat flour with or without supplemental essential amino acids. A control diet with white fish meal and brown fish meal as the only protein sources was included. Practical ingredients were substituted from $40\%$ up to $65\%$ for portions of the fish meals in the control diet. Essential amino acids (EAA) were added to the diets for balancing EAA composition of each dietary protein source. In addition, these experimental diets were compared with raw fish-based moist pellet containing $50\%$ frozen horse mackerel and $50\%$ commercial binder meal. Results indicated that animal and plant protein sources could substitute for fish meal up to $55\%$ in diet without any adverse effects on growth and chemical composition of fish. Fish growth, body composition, nutrient utilization, and cost of fish production are discussed in relation to nutritional values of the dietary protein sources.