• Journal of Aquaculture
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• v.6 no.3
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• pp.213-219
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• 1993

Two studies were carried out: to compare commercial flounder diets (C1-C6) with a laboratory-formulated diet (S), and to evaluate moist pellet (MP) prepared with or without raw fish for olive flounder culture. In experiment I, three replicates of 20 fish (42 g in average) each were fed S or each of C1-C6 for four weeks at $17^{\circ}C. For experiment 2, three replicates of 400 fish (78 g in average) each were fed $100\%$ laboratory-formulated grower diet (G), 50\%\;G+50\;%$ frozen mackerel containing $70\%$ moisture or $50\%\;C6$ (the same diet as that used in Exp. 1) +$50\%$ frozen mackerel for six weeks. Weight gain of fish fed S was significantly (P< 0.05) higher than that of fish fed C2 or C3 (26.7 vs 15.4 or 17.5g/fish over the 4-week period, respectively). Feed efficiency was significantly (p<; 0.05) lower in fish fed C2 than in fish fed S but was not different (P> 0.05) between the fish fed Sand the other commercial diets. No significant differences in weight gain were found among the fish fed $100\%\;G,\;50\%\;G+50\%$ frozen mackerel or $50\%$ C6+frozen mackerel. The results of our studies indicate that most of the commercial flounder diets can be improved for better growth, when we compared these diets with a laboratory-formulated diet, and the growth of flounder fed MP containing no raw fish was as good as that of those fed MP prepared with raw fish.

• Journal of Aquaculture
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• v.20 no.1
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• pp.51-55
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• 2007

This study was conducted to evaluate the muscle quality of the olive flounder fed on extruded pellet (EP) diets compared with a raw fish moist pellet (MP) diet for olive flounder, Paralichthys olivaceus in a commercial scale for a year. The sensory and physical qualities and palatable compounds were compared for evaluation of muscle quality in fish. Four diets were formulated for this experiment: two experimental EP diets (EP 1 and 2), one commercial EP diet (CEP) and MP diet. Crude lipid of fish fed EP1 and EP2 was significantly higher (P<0.05) than that of fish fed CEP, but not significantly different from that of fish fed MP (P>0.05). In the palatable compounds, the free amino acids composition were much alike in that of all the diets. Proline, glycine and alanine from fish fed diet EPs were the most abundant compound among amino acid compositions. There was little difference in the free amino acid compositions of all flounder from localities and the growing conditions between wild and cultured fishes. Taurine of fish fed EP1 was dominantly high over that of fish fed EP2, CEP and MP. In all nucleotides and their related compounds, ATP and IMP from fish fed EP diets were higher (P<0.05) than those of fish fed MP. In the sensory score, overall-acceptability of fish fed EP2 were significantly higher (P<0.05) than that of fish fed EP1, CEP and MP. Hardness of physical properties from fish fed EP2 was significantly higher (P<0.05) than those of fish fed CEP (P<0.01). These results strongly suggest that diets EP could be developed to replace MP diet for the grow-out stage of olive flounder without adverse effect on growth performance.

• Journal of fish pathology
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• v.23 no.3
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• pp.389-398
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• 2010

Effects of various concentration of yuzu Citrus junos Siebold ex Tanaka in the diets on growth, blood chemistry and disease resistance of olive flounder were determined. Fifteen hundred fish averaging 200~270g were fed on moist pellet containing yuzu at the concentrations of 0%(control), 2.5%, 5% and 7.5% for 3 months. After feeding trial, weight gain of fish fed 2.5% and 5.0% yuza diet was higher than those of fish fed 0% and 7.5% yuza diet but not significant(P>0.05). No differences in hematological and physiological indices of olive flounder were found among the experimental diets except for total cholesterol. Serum lysozyme activity was not significantly different among fish fed experimental diets but bactericidal activity of fish fed 7.5% yuza diet was significantly different from those of fish fed 0, 2.5 and 5% Yuza diets. Survival rates of fish fed 2.5% yuza diet at experimental infection with Edwardsiella tarda and Streptococcus sp. were higher than those of the other experimental groups but not significant. In conclusion, Dietary inclusion of 2.5~5% yuzu seems to have positive effects for fish health condition and disease resistance.

• Journal of Aquaculture
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• v.9 no.3
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• pp.233-237
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• 1996

A growth study was conducted to investigate the effect of stocking density on performance of juvenile fat cod (Hexagrammos otakii Jordan et Starks.). Fish averaging 13 g were stocked into duplicate tanks ($250\;{\ell}$ each) at four different densities of 330 g/$100\;{\ell},\;660\;g/100\;{\ell},\;990\;g/\;100\;{\ell}$, and $1330\;g/100\;{\ell}$, and fed MP diet containing $50\%$ frozen horse mackerel and $50\%$ commercial binder meal for 2 months. Weight gain, feed efficiency, survival rate, and protein retention were decreased as density increased. Whereas these parameters were not significantly different (P>0.01) fish stocked at initial stocking densities of $330\;g/100\;{\ell},\;660\;/g/100\;{\ell}\;and\;990\;g/100\;{\ell}$. Moisture and lipid content of whole body were not affected by stocking densities (P>0.01). These results indicate that stocking density should be considered, and $1{\~}2$ kg fish/$100\;{\ell}$ final stocking density for juvenile fat cod could be used to decrease production cost for the indoor tank (culture) system.

• 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.

• 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).