• Plant Resources
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• v.7 no.1
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• pp.1-6
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• 2004

In vitro proliferation system was achieved by using nodal segment excised from greenhouse grown juvenile stock plants of Alnus japonica. Stem explants were cultured on MS medium supplemented with different plant growth regulators of cytokinin and/or their combinations. The most effective cytokinin source was the combination of zeatin 2.0 mg/L and TDZ 0.05 mg/L producing the average number of shoots (16.8 $\pm$ 3.6). In addition, healthy roots were formed after small clumps of shoots were transferred to half strength of MS medium containing IBA 0.02 mg/L with optimal rooting capacity. Soil acclimatization was successfully conducted in cell tray containing artificially mixed soil with 92 % survival rate.

• Fisheries and Aquatic Sciences
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• v.20 no.3
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• pp.4.1-4.6
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• 2017

Juvenile Anoplopoma fimbria (mean length $16.8{\pm}2.2cm$, and mean weight $72.8{\pm}5.4g$) were exposed for 2 months with different levels of ammonia (0, 0.25, 0.50, 0.75, 1.00, and 1.25 mg/L). Growth performances such as daily length gain, daily weight gain, condition factor, and hepatosomatic index were significantly decreased by ammonia exposure. Hematological parameters such as red blood cell (RBC) count, hematocrit, and hemoglobin were also significantly decreased. In plasma inorganic components, calcium and magnesium were significantly decreased by ammonia exposure. In plasma organic components, there was no alteration in cholesterol and total protein. In enzyme plasma components, glutamic oxalate transaminase (GOT) and glutamic pyruvate transaminase (GPT) were significantly increased. The results of this study indicated that ammonia exposure can induce significant growth reduction and blood biochemistry alterations of A. fimbria.

• 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.45 no.6
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• pp.679-685
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• 2012

A study was carried out to observe the effects of feed types on the growth, feed preference, and enteric feed transition rate of juvenile starry flounder, Platichthys stellatus for 45 days. Fifty fish (avg. 135 g) were stocked each in replication, and fed a commercial extruded pellet diet (EP, 45% protein) and a moist pellet diet (MP, 65% raw mackerel+35% feed powder in wet basis), respectively. The MP presented the higher performance than that of the EP on the feed efficiency ($68.3{\pm}0.9%$ for EP and $92.3{\pm}4.3%$ for MP) and the specific growth rate ($1.07{\pm}0.07$ for the EP and $1.20{\pm}0.05%$ for the MP). In contrast, the EP showed the higher feed preference in terms of the daily feed intake ($1.57{\pm}0.08%$ for the EP and $1.30{\pm}0.01$ for the MP) and the ad libitum feeding rate after a fast of 72 hours (1.73% for the EP and 1.35% for the MP). The feed transition rate through intestinal canals decreased exponentially in both the EP and the MP, showing the faster transition rate with the EP. In the result, starry flounder appeared to have the better feed preference to the EP, but have the higher feed efficiency and growth performance to the MP.

• Fisheries and Aquatic Sciences
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• v.22 no.5
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• pp.9.1-9.7
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• 2019

The study investigated the changes in growth performance, hematological parameters, plasma components, and stress indicators of juvenile starry flounder, Platichthys stellatus, depending on varying exposure to hexavalent chromium. P. stellatus was exposed to waterborne chromium at 0, 50, 100, 200, and 400 ppb for 4 weeks. The result showed that Cr exposure resulted in decreased daily length gain (DLG), daily weight gain (DWG), condition factor (CF), and hepatosomatic index (HIS) in P. stellatus. In terms of hematological parameters, red blood cell (RBC) count, hematocrit (Ht), and hemoglobin (Hb) significantly decreased at 400 ppb after 2 weeks. In terms of plasma components, inorganic analysis was unchanged and cholesterol, an organic component, considerably increased at 400 ppb after 4 weeks. Plasma enzyme components including glutamic oxalate transaminase (GOT) and glutamic pyruvate transaminase (GPT) were significantly increased. Stress indicators such as cortisol and glucose were notably increased over 100 ppb after 4 weeks with increasing chromium concentration. The results indicate that exposure to waterborne Cr induced toxic effects on growth, hematological parameters, plasma components, and stress indicators.

• Fisheries and Aquatic Sciences
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• v.24 no.9
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• pp.311-317
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• 2021

Inclusion effect of various levels of jack mackerel meal (JMM) acting as feed attractants and/or stimulants in diets on the growth, feed consumption, feed utilization and whole body composition of rockfish was investigated. Three hundred juvenile rockfish were randomly allocated into 15 flow-through tanks. Five experimental diets supplemented with JMM at 0%, 1%, 3%, 5%, and 10% at the expense of anchovy meal were prepared and referred to as the JMM0, JMM1, JMM3, JMM5, and JMM10 diets, respectively. Weight gain, specific growth rate (SGR) and feed consumption of fish tended to improve with dietary levels of JMM. The greatest weight gain, SGR and feed consumption were observed in fish fed the JMM10 diet, followed by the JMM5, JMM3, JMM1, and JMM0 diets, in that order. Condition factor (CF) of fish tended to improve with dietary inclusion levels of JMM. Growth performance, feed consumption and CF of fish tended to improve with dietary inclusion levels of JMM ranging from 0% to 10%.

• Journal of Aquaculture
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• v.19 no.4
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• pp.225-230
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• 2006

A long-term (26 weeks) feeding experiment was conducted to examine the essentiality and requirement of inositol in diets for olive flounder because no information is available in the species. Five casein-gelatin based semi-purified diets were formulated to contain four different levels of myo-inositol (0, 0+antibiotic, 400, 800, and 1600 mg/kg, designated as M0, M0+, M400, M800, and M1600, respectively). One (M0+) of the control diets contained tetracycline hydrochloride (0.4%, wt/wt) as an antibiotic to inhibit biosynthesis of inositol by micro-organism in intestine of fish. Olive flounder at the early juvenile stage (initial body weight 1.22 g) were randomly distributed into fifteen 35 L tanks (48 fish/tank) and fed with one of the experimental diets (3 replicates per diet). At the end of the feeding trial, the weight gain, feed intake, specific growth rate, and protein efficiency ratio of fish fed diets containing higher levels of myo-inositol (M800 & M1600) were significantly higher than those of fish fed the other diets (P<0.05). Feed conversion ratio, survival, hematocrits, and hemoglobin of fish fed experimental diets were not significantly different among all the fish groups. Whole body compositions of fish were not different except for lipid content. The lipid content was significantly different between M0 and M400 diet groups. These results indicate that juvenile olive flounder requires dietary supplementation of myo-inositol in diets for normal growth and its optimum level seems to be approximately 800 mg myo-inositol/kg diet.

• Journal of Aquaculture
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• v.15 no.1
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• pp.15-21
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• 2002

Two groups of juvenile flounders (90 g/each) were fed on moist pellet feed thrice a day for a period of 8 weeks; the first group, reared in 4 circular (6m $\times$ 0.8 m) tanks (1200 flounders/tank), was fed daily (ED) and the second one on alternate days (EO). There was no significant difference in growth and feed conversion ratio (FCR) between these groups. There was also no difference in chemical composition, except in lipid, which was significantly higher (4.1%) in the ED group than the EO group (3.4%). Food intake and gain in the whole body nitrogen (N) were higher in the ED group but there was no significant difference between these groups in N retention; they excreted almost equal amount (114 vs 112 g) of N. Although phosphorus intake was significantly different between these groups, the flounders retained equal amount (0.5 g) of P in their body and excreted also equal amount (27.6 vs 26.0 g/kg weight gain) of p. Energy intake (2528 kJ) of the ED group was higher than that (2116 kJ) of the EO group. However, there was no significant difference in their energy retention efficiency. Clearly, alternate day feeding regimen led to more efficient utilization of food by the juvenile flounder.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.4
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• pp.314-319
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• 2010

This study determined the proper inclusion levels of squid liver powder (SLP) - soy protein concentrate (SPC) premix as a fish meal (FM) substitute in the diet for juvenile olive flounder (Paralichthys olivaceus). All the experimental diets were formulated to be isonitrogenous (50% crude protein) and isocaloric (17.1 kJ energy $g^{-1}$ diet). Five diets were formulated with SLP-(SPC) replacing 0, 25, 50, 75, and 100% of the FM (SLP $(SPC)_0$, SLP $(SPC)_25$, SLP $(SPC)_50$, SLP $(SPC)_75$, and SLP $(SPC)_100$, respectively). Triplicate groups of 12 fish averaging $5.56{\pm}0.10\;g$ ($mean{\pm}SD$) were fed one of the five experimental diets for 7 weeks. The weight gain (WG), specific growth rate (SGR), feed efficiency (FE), and protein efficiency ratio (PER) of fish fed SLP $(SPC)_0$ were significantly (P<0.05) higher than those of fish fed SLP $(SPC)_50$, SLP $(SPC)_75$ and SLP $(SPC)_100$, while those of fish fed SLP $(SPC)_0$ and SLP $(SPC)_25$ were similar. The whole-body crude protein content of fish fed SLP $(SPC)_0$ was significantly (P<0.05) lower than that of fish fed SLP $(SPC)_50$, SLP $(SPC)_75$, and SLP$(SPC)_100$, while those of fish fed SLP $(SPC)_0$ and SLP $(SPC)_25$ were similar. The whole-body crude lipid of fish fed SLP $(SPC)_0$ was significantly (P<0.05) lower than that of fish fed SLP $(SPC)_50$ and SLP $(SPC)_75$, while those of fish fed SLP $(SPC)_0$, SLP $(SPC)_25$ and SLP $(SPC)_100$ were similar. Based on the fish growth performance results obtained from this study, the SLP (SPC) premix can substitute up to 25% of the FM in the diets of juvenile olive flounder.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.3
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• pp.282-288
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• 2002

This study was carried out to investigate the optimum tagging method of the abalone juvenile, Haliotis discus hannai in indoor culture system from May 2000 to January2001. Tagging methods were shell drilling, copper-wire tagging at the respiratory pore and nut gluing on the shell. The attachment rates of the shell showed high in the 2- and 3 cm bolt-nut tagged groups, about over $89.5\%$, whereas shell drilling groups on the shell were about $18.5\%$. The internal coating rates tagged with bolt-nut were over $96.6\%$, while those tagged with copper wire were less than $17.1\%$. Growths in the all marked and tagged experimental groups comparing with control groups were not significantly different (p>0,05). Survivals in all tagging groups except shell drilling and nut gluing groups in the 5 cm abalone were over $95\%, Accordingly, all juvenile groups were not affected by the tagging methods in terms of the growth and survival on the abalones. Based on these results, the micro bolt-nut tagging was the most effective method in abalone.