• Korean Journal of Ichthyology
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• v.29 no.3
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• pp.165-175
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• 2017

To minimize the damage caused by summer season such as high temperature and red tide, this study was conducted to investigate the effect of feeding and starvation on the survival rate, growth, growth restoration and physiological response of red seabream Pagrus major which were reared in marine net cage ($6m{\times}6m{\times}6m$). The feeding group was fed throughout the experiment for 10 weeks, whereas starvation group was not fed for 6 weeks and subsequent refeeding for 4 weeks. Survival rates of feeding and starvation groups were 94.4% and 98.1% respectively. The growth rate of starvation group was significantly lower than feeding group during starvation period, but recovered rapidly after feeding. The nutritional status such as albumin, total protein, total cholesterol, triglyceride also showed similar tendency to the growth data. Hematocrit and hemoglobin levels were higher in the feeding group than the starvation group during starvation period. Aspartate aminotransferase, glucose and total cholesterol were rapidly increased at the same time (in 5 week) in feeding group, whereas starvation group did not significant difference during starvation period. It was shown that the feeding group is more sensitive to stress than the starvation group. Thus, starvation can be applied as a rearing management plan of net cage fish farm in summer season.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.6
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• pp.793-800
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• 2013

This study was conducted to determine the physiological and histological characteristics of starry flounder Platichthys stellatus juveniles to undergo a short/long starvation period and subsequent re-feeding with 2 weeks interval for 65 days. All findings from this study indicate the possibility of a very rapid recovery possibility of starry flounder after short starvation period for 2 or 4 weeks. The mean body weight after 2 and 4 weeks starvation were not significantly different after 65 days. However, the body weight of 6 and 8 weeks starved fishes showed significantly low value than 2 weeks starved fishes. All biomarkers, liver somatic index, RNA/DNA ratio and blood chemistry, in this study showed fast recovery possibility after re-feeding of starry flounder. During the starvation and recovery process, they showed distinct increasing and decreasing tendency. From 21-28 days after re-feeding, most biomarkers reached to their maximum value and thereafter decreased again in 2, 4 and 6 weeks starvation and re-feeding groups. It could be interpreted as a compensatory growth and strategical action against starvation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.2
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• pp.125-133
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• 2008

To investigate the effect of repeated food deprivation and refeeding on the hyperphagia, compensatory growth, feed efficiency, body composition, hepatosomatic index (HSI), and survival rate of the juvenile olive flounder Paralichthys olivaceus, an experiment was conducted for 90 days. Feeding treatments consisted of the following five regimes for 90 days from August to October, 2005: C: daily satiation feeding (control), S1: 1-day satiation feeding after 1-day food deprivation, S2: 1-day satiation feeding after 2-day food deprivation, S3: 1-day satiation feeding after 3-day food deprivation and S4: 1-day satiation feeding after 4-day food deprivation, respectively. Although the monthly feed intake (MFI) of the control was significantly higher than that of all of the starved groups, the daily feed intake (DFI) was more higher in S1, S2, and S3 than that in the control as a result of hyperphagia after starvation. While the feed efficiency in the summer (to day 30) decreased in all of the starved groups with prolongation of the starvation period, the feed efficiency in the autumn (to day 90) was increased with prolongation of the starvation period. The whole body proximate composition and HSI were also affected by starvation. The crude protein, lipid, and HSI decreased with prolongation of the starvation period, whereas the crude ash and moisture increased. The growth rate and condition factor also decreased in proportion to the starvation period. The survival rate was highest in the control and was the lowest in S4. In this study, although hyperphagia occurred in the deprived groups, we knew that the compensatory growth did not always occur.

• Korean Journal of Environmental Biology
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• v.22 no.3
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• pp.351-368
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• 2004

Following the previous experiments, a starvation experiment was conducted to determine the influence of feeding and starvation on the histological and biochemical changes, the morphormetric changes in the sectioned body and the morphometric changes in Rhynchocypris oxycephalus (Sauvage and Dabry). The influence of starvation on nutritional conditions of the histological changes of hepatocyte and intestinal epithelium as hepatosmatic index (HSI), protein, RNA and DNA concentrations of liver in R. oxycephalus was tested. Although the starved group showed higher concentrations of protein, DNA and RNA than the fed group, food deprivation resulted in a decrease in the HSI, hepatocyte nucleus size and nuclear height of the intestinal epithelium. The RNA - DNA ratio appears to be a useful index of nutritional status in R. oxycephalus and may be useful for determining if R. oxycephalus is in a period of rapid or slow growth at the time of sampling. Additionally, the data have been interpreted in detail and some biologically important relationships discussed. The effects of starvation on the morphometrical changes in sectioned body traits, condition factor, viscera index and dressing percentage were determined for evaluating nutritional conditions of R. oxycephalus. Starvation for nine weeks resulted in a decrease in most sectioned traits as well as in condition factor and viscera index (P<0.05). These findings suggest that nutritional parameters used in this study appear to be a useful index for nutritional status in this species. The data has been interpreted in detail and some important body sectioned values of interest to commercial growers discussed. A 75-day study was conducted to determine the effect of starvation on classical and truss parameters in R. oxycephalus. Truss dimensions of almost the entire head and trunk region as well as the abdomen were increased significantly through feeding or starvation (P<0.05). Truss dimensions of the caudal region generally decreased through feeding or starvation, particularly those dimensions at the hind part of the trunk. There were some significant decreases in classical dimensions of the head region during feeding, in relation to body depth characteristics in the trunk and caudal region during starvation, whereas there was only one decreasing classical dimension in the caudal region during feeding. The results of this study indicate that application of the truss network as a character set enforces classical coverage across the body form, discrimination among experimental groups thus being enhanced. Considering that the dimension of the lower part of the head and some truss and classical dimensions were least affected by feeding and starvation, these dimensions may then be useful as a taxonomical indicator to discriminate the species of Rhynchocypris sp. The value of trunk region dimensions with a large component of body depth in R. oxycephalus is most likely to be compromised by variability related to differences in feeding regimes of fish in different habitats.

• Development and Reproduction
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• v.22 no.4
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• pp.319-329
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• 2018

The experiment was conducted for 210 days to determine the effect of feeding, and starvation, and exposure to sodium nitrite ($NaNO_2$) on the survival, physiological changes, hematological parameter, and stress response of Far Eastern catfish, Silurus asotus. The survival of the starved group was lower than that of the fed group during the experiment. Starvation resulted in retardation of growth, which provides an example of fish that failed to continue to grow and remain in a good condition. Blood analyses (cortisol and glucose) showed significant differences of stress response between the fed and starved groups exposed to $NaNO_2$ at the conclusion of the experiment (p<0.05). These results suggest that all nutritional parameters used for starvation and feeding with $NaNO_2$ stress in this experiment appear to be a useful index of nutritional status in Far Eastern catfish.

• Journal of Aquaculture
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• v.19 no.3
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• pp.183-187
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• 2006

A 12-week experiment was conducted to determine the effect of feeding and starvation on survival, growth and the phenotypic trait in olive flounder, Paralichthys olivaceus. Survival and growth of the starved fish group was significantly lower than those of the fed fish group throughout the experiment. Starvation resulted in a retardation in growth, which provided the examples of the reduction in final body weight, growth rate, specific growth rate and condition factor whereas the fed fish group grew well and maintained in good condition. The starved fish group had lower gutted body weight, but similar viscera index and dressing percentage compared to those of the fed fish group. These results suggested that the phenotypic trait used fur starvation and feeding in this study appeared to be an useful index of the nutritional status in olive flounder.

• Fisheries and Aquatic Sciences
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• v.14 no.4
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• pp.411-416
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• 2011

We investigated the nutritional status of the melania snail (Semisulcospira gottschei) using RNA/DNA ratios to evaluate the effect of feeding conditions (artificial versus natural) on the reaction times of the snails in a time course following starvation. In the short experiments (48 h), the RNA/DNA ratios of the artificial feeding groups were significantly higher than those of the natural groups. While two RNA/DNA ratio peaks were observed in the artificial food group during daytime, the natural food group showed a higher ratio at night. Under starvation conditions, the RNA content decreased whereas the DNA content was constant. The RNA/DNA ratios of the freshwater snail in both groups dramatically decreased after starvation and remained constant until the end of the experiment. We verified that the RNA/DNA ratio serves as an index of nutritional condition with respect to the effect of dietary differences. These results are important for understanding optimized aquaculture rearing conditions for this important commercial freshwater snail.

• Journal of Aquaculture
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• v.11 no.4
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• pp.521-528
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• 1998

The influence of starvation on survival, growth and feeding incidence of larval tiger puffer Takifugu rubripes was investigated for 16 days after let them hatched at the temperature of 16.5~18.5${\circ}C$. The effect by delayed initial feeding on larvace was also studied. Almost all larvae began to be fed from the stage of yolk absorption about 5 days after hatching, in which rearing trials revealed that their survival and growth were influenced by food availability. Survival of unfed larvae, which stated to decrease drastically since the oil globule was exhausted about 9 days after hatching, dropped to 50% and 0% respectively on the 11.5th and 16th day. the difference of growth between fed and unfed larvae came into sight on about 5th day after hatching when the initial feeding was started, and had reduced in proportion to the length of starvation period. The condition factors for the unfed larvae were lower than thost of the fed. Of the larvae which had starved less than 5 days, more than 80% could consume food upon feeding. No fish had the ability in having food after 10 days. It appeared that the turning point of recover for the starving larvae came on 7th or 8th day. Their taking-food ability seemed to be affected by the change in swimming activity which depended on the duration of starvation. For the seed production of tiger puffer, therefore, feeding should be initiated as soon as possible, so as to enhance the production and survival of healthy seeds.

• Korean Journal of Ichthyology
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• v.20 no.2
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• pp.81-89
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• 2008

An experiment was conducted for 80 days to determine the effect of feeding and starvation on the survival, growth, gonad-somatic index (GSI), hepato-somatic index (HSI), viscera index (LSI), the morphometric changes and hematological parameter in a cultured catfish, Silurus asotus. The survival and growth of the starved group was lower than those of the fed group during the experiment. Starvation resulted in retardation of growth, which provides examples of the reduction of final body weight, growth rate of body weight, specific growth rate and condition factor, whereas the fed group continued to grow and remained in good condition. Blood analysis (cortisol, glucose, aspartate aminotransferase, alanine aminotransferase, red blood cell and hemoglobin) showed significant differences between the fed and starved groups at the end of the experiment. These results suggest that all nutritional parameters used for starvation and feeding in this study appear to be a useful index of nutritional status in the cultured catfish.

• Development and Reproduction
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• v.17 no.4
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• pp.399-407
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• 2013

Morphological changes in the reared rock bream, Oplegnathus fasciatus, from hatching to six days after hatching were examined during the early growth stage under starvation. All the larvae died within five days when feeding was delayed for three days after hatching. These results imply that initial larval food should be supplied within two days of hatching. Changes in the pectoral angle and the ratios of eye height to head height, gut height to standard length, and gut height to myotome height in the rock bream are alternative indicators for the identification of starving fish. These indicators might prove useful in evaluating the successful transition from endogenous to exogenous feeding in this species.