• The Korean Journal of Malacology
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• v.27 no.3
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• pp.175-180
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• 2011

The investigated amounts according to microalgae for stable supply of artificial seed of the hard clam, Meretrix petechialis and also observed the effect according to the repower of the microalgae after the specified period starvation. The stage of specimen used in the test was the D-shaped larva. The microalgae was Chaetoceros calcitrans, Isochrysis galbana and Nannochloris oculata. When the mixture of Chaetoceros calcitrans, Isochrysis galbana and Nannochloris oculata or alone C. calcitrans as food was supplied with 3,000-5,000 cells/ind., it turned to be the most effective. When the food was provided after starvation for some period, the shell length of D-shaped larva was grown to over $192.5{\mu}m$ at fourth day from the initial feeding. The survival rate tended to be lower, the longer the starvation period.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.1
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• pp.69-82
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• 1994

In order to find out physiological effects of diets supplemented with seamustard (Undaria pinnatifida) on the growth, survival rate, body compositions and blood properties of young rockfishes (Sebastes schlegeli) in range of average total length from $2.99{\pm}0.23\;cm\;to\;18.52{\pm}1.07\;cm$ and average body weight from $1.03{\pm}0.18\;g\;to\;120.64{\pm}19.32\;g$, experiments were performed for 140 days by feeding four experimental diets supplemented with $0\%,\;3\%,\;5\%\;and\;7\%$ of seamustard powder. In addition, the tests on tolerance of the fishes against low $O_2$ saturation and starvation were carried out after the feeding experiments. The fishes fed diet supplemented with $5\%$ of seamustard powder revealed the best results in growth of total length and body weight. Crude lipid content in the whole viscera of fishes fed diets supplemented with seamustard powder was higher than that of fishes fed diet without seamustard powder, while the moisture, crude protein, crude lipid and crude ash composition in the dorsal muscle did not show any remarkable differences among diet groups with or without seamustard powder. Hematocrit and mean number of red blood cell in fishes fed diets supplemented with seamustard powder was elevated, despite of no notable changes in mean corpuscular volume, mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration. The resistance of the fish to low $O_2$ saturation was elevated by feeding seamustard powder. Upon the starvation of fish for 31 days after the feeding experiments, body weight loss of three groups fed diets with seamustard was smaller compared with the group fed diet without seamustard.

• Journal of Life Science
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• v.25 no.7
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• pp.780-785
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• 2015

Dietary intake and bioavailability of phorotannins in abalone was investigated after feeding with the phlorotannin-rich brown seaweed Ecklonia stolonifera after 4 days starvation. Reverse-phase high-performance liquid chromatography (RP-HPLC) affords isolation and quantification of the major phlorotannins of 7-phloroeckol and eckol, which were identified by mass spectrometry and nuclear magnetic resonance. Abalone growth and feed consumption rates were similar when fed either with the E. stolonifera or the common feed seaweed Saccharina japonica for 20 days. Throughout the feeding period, 7-phloroeckolol was accumulated in the abalone flesh tissue up to an average of 0.58±0.13 mg/g dry weight after 6 days. Eckol was reached to 0.25±0.05 mg/g dry tissue after 6 days, and maintained the level until end of feeding period. By feeding S. japonica as a control, no phlorotannins were detected in the abalone tissues. Both of the abalone, fed with E. stolonifera or S. japonica, had enzymes that decomposed 7-phloroeckol and eckol in muscle tissues, with similar degradation rates of −0.05 or less and −0.05 mg/ml/hr, respectively. Phlorotannins were reduced by constitutive enzymes in abalone tissues. Therefore, value-added abalone containing bioactive phlorotannins can be produced by simply changing the feed to the phlorotannin-rich brown seaweed E. stolonifera 6 days before harvest.

• Journal of Aquaculture
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• v.11 no.3
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• pp.363-369
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• 1998

The effects of feeding frequency on growth and body composition of juvenile chum salmon (Oncorhynchus keta) were compared among five groups at different feeding frequencies : 4 times daily, 2 times daily, once a day, 4 times every other day, and 2 times every other day. The effects of 1~2 nonfeeding days per week were also examined. Growth rates, feed efficiencies, survival rates, and condition factors of fish fed twice and 4 times daily were higher than for the other groups, and were also higher for fish fed 6~7 days per week than those fed 5 days per week. Hepatocyte nuclei of fish were larger in the daily feeding groups than others, which suggested fish daily fed would have higher methabolic rate. Theses results suggested that captive juvenile chum salmon should be fed 2 or more times per day, and 6~7 days per week.

• Ocean and Polar Research
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• v.26 no.3
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• pp.415-423
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• 2004

An experiment was conducted to investigate the differences of total ammonia nitrogen (TAN) excretion rates and feces production rates among the offsprings from cultured Japanese strain (JJ, mean BW; $17.1{\pm}0.1g$), intraspecific hybrid strain between cultured Japanese and selected Korean strain (JK, mean BW: $17.1{\pm}0.1g$) and selected Korean strain(KK, mean BW: $21.5{\pm}0.1g$) of red sea bream in order to compare their dietary protein utilization efficiency. Fish were hand-fed with a commercial diet containing 46.7% crude protein for 2 weeks, three times daily 09:00, 13:00 and 17:00. After daily feeding, the TAN excretion rates reached peaks of 49.03, 58.75 and 36.26mg/kg fish/hr for the JJ, JK and KK strain, respectively, during the daytime. The value of the KK strain was significantly lower than that of the JJ and JX shuin (P<0.05), however daily TAN excretion rates of the JJ, JK and KK strain were not different (P>0.05). When fish were fed at satiation after 4 days of starvation, TAN excretion rates reached the maximum values 4 hours after the feeding fur the KK (31.23 mg/kg fish/hr) and 6 hours after the feeding fur the JJ (44.19 mg/tg fish/hr) and JK strain (41.70 mg/kg fish/hr). After 3 days of starvation, the daily endogenous TAU excretion rates (ETE) for the JJ, JK. and KK strain were 286.91, 215.66 and 179.29mg/kg fish/day, respectively. The value of the KK strain was lower than that of the JJ and JK strain (P<0.05). The total feces production rates of the JJ, JK and KK strain were not significantly different, however the proportions of feces production rates by time for the JJ, JK and KK strain were different (P<0.05). As overall results, efficiency of dietary protein utilization of JJ, JK and KK seems to be different and KK strain could offer a desirable option for aquaculture purpose.

• Korean Journal of Ichthyology
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• v.2 no.2
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• pp.138-148
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• 1990

The influence of starvation on morphological change of the red sea bream larvae was examined at Song-ji fish hatchery, Tongyong-Gun, Kyongnam Provice in July 1988. The results obtained are as follows: 1) The larvae of red sea bream began to feed on rotifers in 2 days after hatching. In case of non-feeding, all of the larvae died in 5 days after hatching and the larvae which feeding delayed 1 and 2 days from normal first feeding schedule also died 100 in 6 days after hatching. 2) With the exhaustion of the yolk, the total length, body length, myotome height and gut height of unfed larvae decreased. 3) The ratio of height to myotome height in unfed larvae has declined most rapidly compare to other demensions while starving. At 5 days after hatching, the ratios of these of starving larvae and fed larvae were 0.306 and 0.010, respectively. 4) The morphology of starving larvae at 6 days after hatching are characterized as sharpened jaw, projected edge of lower part of clavicle and slender gut.

• Fisheries and Aquatic Sciences
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• v.18 no.2
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• pp.165-171
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• 2015

Abalone containing phlorotannins is produced by feeding the phlorotannin-rich brown seaweed Eisenia bicyclis after 4 days of starvation. Reverse-phase high-performance liquid chromatography (RP-HPLC) was used to isolate and quantify phlorotannins, which were identified by mass spectrometry and [$^1H$]-nuclear magnetic resonance to be the P1 compound, 7-phloroeckol, and eckol. When E. bicyclis was used as feed, P1 compound accumulated to an average of 1.60 mg/g dry weight of abalone muscle tissue after 18 d, 7-phloroeckolol to 0.21 mg/g after 16 d, and eckol to 0.22 mg/g after 12 d. Saccharina japonica was used as a control feed, and the abalone showed little or no accumulation of phlorotannins in muscle tissue. Feed consumption and growth rate were very similar when either E. bicyclis or S. japonica was fed for 20 d. Half-maximal reductions in the levels of P1 compound, 7-phloroeckol, and eckol accumulation were attained in 1.5, 1.9, and 3.4 days, respectively, after the feed was switched from E. bicyclis to S. japonica. Value-added abalone containing bioactive phlorotannins can be produced by simply changing the feed to the phlorotannin-rich E. bicyclis 18 d prior to harvesting.

• International Journal of Industrial Entomology and Biomaterials
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• v.19 no.2
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• pp.243-248
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• 2009

The Larval critical weight is the minimal mass at which further growth in not necessary for a normal time course to pupation. Larval critical weight (Lcw), pupal critical weight (Pcw) and adult critical weight (Acw) of different breeds of Bombyx mori L. were determined through starvation (food deprivation). The Lcw was found to be about 938.46, 2397.26, 2283.57 and 2220.97 mg in males and 1118.15, 2681.04, 2604.9 and 2455.88 mg in females of the multivoltine breed (Nistari), Bivoltine breeds (P5 & NB18) and their hybrid (P5$\times$NB18) respectively. Bivoltine breed P5 took more time (3.35 days) followed by NB18 (3.13 days) & P5$\times$NB18 (3.02 days) to attain larval critical weight (In $5^{th}$ Instar) than the multivoltine breed Nistari (2.42 days). Decrease in weight from larval maximal weight to pupal weight and to adult weight was also observed more in multivoltine than bivoltines, which may be due to more latent feeding period in bivoltines. Since Lcw is a stable character and independent of environment, it could be utilized for characterization of silkworm breeds to assess the quality of an insect.

• 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.

• Journal of Aquaculture
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• v.16 no.1
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• pp.1-7
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• 2003

A new technique combining forced-feeding and dorsal aorta cannulation was developed to monitor concentration of nutritions in the blood circulation and their metabolites in rainbow trout. To study the effect of dorsal aorta cannulation on stress, 30 rainbow trout (523$\pm$5.4 g; Mean$\pm$SD) were divided into 6 groups of 5 individuals each. A group was anesthetized and blood samples were taken at 0, 3, 6, 12, 24 or 48 h after dorsal aorta cannulation. Hematocrit peaked at 6 h and returned to 0 values by 12 h after dorsal aorta cannulation. Plasma cortisol and glucose concentrations also peaked at 6 h and returned to 0 values by 48 h after dorsal aorta cannulation. Based on the plasma cortisol and glucose concentrations, the rainbow trout recovered from the operation of dorsal aorta cannulation within 48 h. To compare the patterns of plasma free amino acid concentrations after force-feeding in the fish with dorsal aorta cannulation, 5 dorsal aorta cannulated individuals (511$\pm$6.2 g) were kept in a cage. After 48 h starvation, they were anesthetized and blood samples were taken at 0, 4, 8, 12, 24, 36 or 48 h after forced-feeding. The concentration of all plasma free amino acids, except isoleucine, leucine, phenylalanine, and tryptophan, also peaked at 4 h and returned to 0 values by 24 h after feeding. The combined technique allows forced-feeding and repeated sampling of blood in rainbow trout with minimum stress.