• Asian-Australasian Journal of Animal Sciences
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• v.25 no.8
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• pp.1138-1144
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• 2012

This study was conducted to evaluate the efficacy of the dipeptide form of phenylalanine as a new source of amino acid in terms of growth performance and whole-body amino acid composition in comparison to the free form for red seabream (Pagrus major). Fish ($1.46{\pm}0.001g$) were fed four isonitrogenous and isocaloric experimental diets containing 0.7 or 1.4% phenylalanine either in free or dipeptide form. A feeding trial was carried out in three replicates and the fish were fed to apparent satiation for six weeks. At the end of the feeding trial, feed intake of fish was influenced by both phenylalanine form and level and significantly higher values were obtained at an inclusion level of 0.7% and by the use of dipeptide form. However, the other growth parameters did not significantly differ among treatments. Whole-body amino acid compositions revealed no significant changes in concentrations of both essential and non-essential amino acids regardless of the increase in phenylalanine levels or the use of its different forms. The finding in this study indicates that juvenile red seabream can utilize dipeptide phenylalanine as efficiently as free form without any undesirable effects on growth performance or whole-body amino acid composition.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.5
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• pp.648-656
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• 2016

The age and growth of jack mackerel Trachurus japonicus caught by large purse seine fishery were studied during August 2004 and May 2005. Otoliths of 472 fish were observed under reflected light, and translucent zones made on the post-rostrum axis were regarded as annual marks. Monthly changes in the marginal index indicated that the translucent zone was formed once a year, mainly in March-April, which was coincident with the peak spawning time of jack mackerel. The estimated ages were 0-6 years, corresponding to a fork length (FL) range of 13 to 38 cm. Most obtained individuals were 2-year-old fish, followed by 1-year-old fish. The mean fork length at age from otolith reading (sex combined) was applied to the von Bertalanffy equation and growth parameters were estimated: L_∞ = 38.29 cm FL, k = 0.31 years⁻¹, t₀ = −0.81 years.

• 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.

• Applied Biological Chemistry
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• v.50 no.1
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• pp.42-47
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• 2007

Effect of chlorine dioxide ($ClO_2$) treatment on the microbial and physicochemical changes of fish paste was investigated. Fish paste samples were treated with 5, 10, and 50 ppm of $ClO_2$ solution, respectively, After $ClO_2$ treatment, fish paste samples were individually packaged and stored at 4$^{\circ}C$. The initial microbial loads of samples were 3.8 log CFU/g in total bacterial count, and 2.5 log CFU/g in yeasts and molds. Microbial growth of fish paste during storage showed that populations of total bacteria, yeast and mold were significantly reduced by $ClO_2$ treatment. In particular, the treatment of 50 ppm $ClO_2$ decreased total bacterial count the most significantly among the $ClO_2$ treated fish pastes. The pH and VBN of fish paste decreased with increasing $ClO_2$ concentration. Thiobarbituric acid reacted substance (TBARS) values of treated fish paste increased during storage, regardless of $ClO_2$ concentration. This study showed that 50 ppm chloride dioxide was the optimum dose level to extend the shelf-life of fish paste.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.6
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• pp.790-795
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• 2014

A feeding trial was conducted to investigate the effects of dietary carotenoids sources on growth and skin color of red- and white-colored fancy carp Cyprinus carpio var. koi. Nine experimental diets (designated as Con, CP, PA, SP, OP, MB, TO, BE and PO) were formulated to contain Carophyll Pink, red paprika, Spirulina, Opuntia, mandarin bark, tomato, beet and Porphyra, respectively. Each experimental diet was fed to two replicate groups of fish (22.9 g/fish) to visual satiation three times a day for 8 weeks. Weight gain and feed efficiency of fish fed the diets containing Spirulina or Opuntia were higher than those of fish fed the control diet (P<0.05). The values of $a^*$, $L^*$ and $b^*$ of fish skin were significantly changed by dietary carotenoids sources (P<0.05). The $a^*$ values of fish fed the diets containing Carophyll Pink, red paprika and Spirulina were higher than those of fish fed other diets (P<0.05). The skin total carotenoids of fish fed the diets containing Spirulina and Opuntia were higher than those of others (P>0.05). Based on the results of this study, it can be concluded that dietary inclusion of red paprika and Spirulina pacifica could increase the skin redness of red- and white-colored fancy carp.

• Journal of Aquaculture
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• v.10 no.2
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• pp.163-169
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• 1997

An experiment was conducted to determine the effects of feeding extruded-floating (EP), slow-sinking (SP), fast-sinking (FP) or moist (MP) prepared with two different levels of fish meal, respectively, on the growth, feed efficiency and body composition in Korean rockfish (Sebastes schlegeli). Triplicate groups of the 50 fish averaging 75g were fed each of the following diets : high fish meal (72% in diet)-EP, low fish meal SP, low fish meal-FP and low fish meal-MP for 15 weeks. Dietary fish meal levels or pellet types did not influence weight gain, feed efficiency and bo요 composition of the fish (P>0.05). Findings showed that each of EP, SP or FP can by used as a practical type of diet for Koran rockfish.

• Journal of Fisheries and Marine Sciences Education
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• v.21 no.4
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• pp.556-561
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• 2009

This study was conducted to evaluate the laboratory formulated extruded pellet (EP) for olive flounder Paralichthys olivaceus in the East Sea. Three replicate groups of 3,200 fish per each tank (initial weight of $28.1{\pm}0.2g$) were fed one of the two EPs (EP and CEP) and Moist pellet (MP) for 16 months in a commercial farm (Pohang, Korea). Survival was not significantly affected by experimental diets (P>0.05). Weight gain and specific growth rate of fish fed the EP were not significantly different from those of fish fed the MP, but that of fish fed CEP was significantly lower than that of fish fed EP and MP (P<0.05). Feed efficiency and protein efficiency ratio of fish fed the EP was significantly higher than those of fish fed MP (P<0.05), but not significantly different from those of fish fed CEP (P>0.05). The Contents of moisture, crude protein and crude lipid in the dorsal muscle were not significantly different among all groups (P>0.05). These results clearly indicated that the laboratory formulated extruded pellet used in this study can be developed to replace the moist pellet without affecting any growth performance of olive flounder in the commercial farm feeding trail.

• Journal of Aquaculture
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• v.7 no.1
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• pp.63-76
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• 1994

The effects of different dietary lipids on growth, body chemical composition, and nutrient partition of the Korean rockfish (43 g of initial mean weight) were studied. Fish were fed three experimental diets containing 1) $4.5\%$ squid liver oil, 2) $1\%$ squid liver oil and $3.5\%$ beef tallow, and 3) $1\%$ squid liver oil and $3.5\%$ soybean oil. Growth and feed efficiency were detarmined during a 19-week feeding period at water temperature of $15.5^{\circ}C$, and at the end of which body chemical compositions were analyzed. Remained fish were fasted for 45 days, and four fish were taken at 6, 12 and 24 hours, and 3, 15 and 45 days after the fasting to determine tissue compositions and hematological changes. Growth, feed efficiency, protein and lipid retention efficiency, hepatosomatic index(HSI), viscerosomatic index (VSI), and chemical composition of whole body and dorsal muscle were not affected by the different dietary lipids. Liver moisture content of fish fed squid liver oil diet was higher than that of fish fed beef tallow or soybean oil diet. Liver lipid content of fish fed beef tallow diet was higher than that of fish fed the other diets. Fatty acid composition of dorsal muscle and liver were affected by the different dietary lipids ; high levels of 20 : 5n-3 and 22 : 6n-3 from fish fed the diet containing squid liver oil, 18 : 1 from fish fed the diet containing beef tallow, and high 18 : 2n-6 and 18 : 3n-3 from fish fed the diet containing soybean oil were observed. Both HSI and VSI of fish fed three diets decreased with time after the begining of starvation. Liver glycogen did not change during the first 15 days of starvation and decreased thereafter, and that was not affected by the different dietary lipids. Lipid and protein contents in the dorsal muscle of fish decreased up to 15 days of starvation and remained unchanged thereafter, these were not different from each other. Glucose, free fatty acid, triglyceride and phospholipid concentrations in Fish serum were varied for the first 15 days of starvation, after that the concentrations of fish serum remained relatively stable in all the treatment groups with prolonged starvation. The results indicate that Korean rockfish can utilize fish oil, animal fat or vegetable oil equally as energy source when n-3HUF A is adquate.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.5
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• pp.620-627
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• 2016

A 60-day experiment was conducted to determine the effect of feeding and starvation on the survival, growth, and blood parameters of red sea bream Pagrus major. The starved group was not fed during the first 32 days of the experiment and was then fed for 28 days. The growth rate of the starved fish group was significantly lower than that of the fed fish group. Starvation resulted in growth retardation and reductions in final body weight, growth rate, specific growth rate, and condition factor, whereas the fed fish group grew well and maintained a good condition. The growth rate of the starved group that was refed was higher than that of the fed group. Red blood cells, hematocrit, and hemoglobin showed no significant differences between the fed and starved groups. The cortisol and glucose levels of the fed group of juveniles were higher than those of the starved group. The cortisol levels of the starved group of adults were higher than those of the fed group, whereas the glucose levels of the starved group were lower than those of the fed group. These results suggest that the survival, growth, and hematological parameters used to reflect starvation and feeding in this study provide a useful index of physiological response and survival rate in red sea bream.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.5
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• pp.774-778
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• 1998

The effect of insulin-like growth factor-I (IGF-I) on circulating insulin-like growth factor binding proteins (IGFBPs) in the Korean rockfish, Sebastes schlegeli, was assessed after injected of recombinant human IGF-I (6 $\mu$g/100 g body weight). Growth and metabolic status of each fish were assessed by determing body length and body weight changes, and serum glucose concentration. Serum IGF binding proteins concentrations were assessed by the Western ligand blot procedure using $^{125}I$-labeled human IGF-I tracer. The fish received IGF-I were Heavier than the saline-injected control fish after 2 weeks of treatment. Plasma IGFBP-3 concentration inclosed, but plasma IGFBP-1 and glucose levels decreased significantly after administration. Taken together, the findings of this study suggest that human IGF-I is biologically active in Korean rockfish and may be of significance in metabolic and growth-related processes.