• 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.

• The Korean Journal of Malacology
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• v.30 no.3
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• pp.227-234
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• 2014

The effect of different feeding rate on the growth and survival rate of the abalone, Haliotis discus hannai, were investigated in marine net cage culture and indoor tank culture. Feeding rate is determined that was fed 5, 10, 15 and 20 percentage to abalone at body weight once daily : 5 daily feeding rate (DFR), 10DFR, 15DFR and 20DFR. After that, it was conducted to reared during thirteen month with two replicates in net-cage culture and indoor tank culture. In the growth performance of reared abalone (initial mean shell length $54.18{\pm}7.39mm$) in net cage culture, that the absolute growth rate (ARG), daily growth rate (DGR) and specific growth rate (SGR) to the shell length and shell breadth, as well as weight gain (WG), daily weight gain (DWG) and specific weight gain (SWG) to body weight of 20DFR were lower than those of different groups (P < 0.05). Also, survival rates of 20DFR was lower than those of different groups (P < 0.05). In the growth performance of reared abalone (initial mean shell length $49.70{\pm}2.28mm$) in indoor tank culture, that the ARG, DGR and SGR to the shell length and shell breadth, as well as WG, DWG and SWG to body weight of 5DFR and 10DFR were lower than those of different groups (P < 0.05). And also, survival rates of 20DFR was lower than those of different groups (P < 0.05). Therefore, these results is showed that the daily feeding rate for natural feed in net-cage culture and indoor tank culture should be to supply among 5-10 percents, taking into account growth, survival rate and economical efficiency.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.9
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• pp.1276-1284
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• 2012

A 12-wk experiment was conducted to examine the hematological changes, survival, and respiratory exchange in the olive flounder, Paralichthys olivaceus, during starvation. The growth, survival and respiratory exchange rates of the starved group were lower than those of the fed group during the experiment. Blood analysis, including hematocrit, hemoglobin, red blood cells, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, and mean corpuscular volume, did not differ significantly (p>0.05) between the fed and starved groups at the end of the experiment. There were no significant differences in plasma cortisol, glucose, $Na^+$, $Cl^-$, $K^+$, or aspartate aminotransferase between the fed and starved groups (p>0.05). Alanine aminotransferase levels were higher in the starved group than in the fed group, whereas plasma osmolality was lower in the starved group than in the fed group. It was shown that starved fish had various problems after four weeks, which did not occur in the fed group. Long-term starvation is infrequent in aquaculture farms. However, starvation studies of this kind are very useful for a basic understanding of how physiological changes affect fish health, life expectancy, and growth.

• Journal of Aquaculture
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• v.10 no.2
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• pp.123-131
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• 1997

Growth of triploid abalone, Haliotis discus hannai induced by cody (3$^{\circ}C$) shock and its feed efficiency were investigated from larva to adult for 51 months. After 51 months from triploidy induction, the triploid abalones have outgrown to diploid abalones in shell length and total weight. Triploid abalones with inhibition of extrusion of first polar body (3n-1pb) were outgrown to diploid abalones, however, triploid abalones with inhibition of extrusion of second polar body (3n-2pb) were not significantly different from diploid controls in shell length and total weight through the whole rearing period (P<0.05), because of their heterozygosity differences. Daily feeding rates and feed conversion rates decreased with the growth of abalones and both rates had no differnce between two experimental groups. After 51 months from inducing triploid, conditin index of triploid abalone (64.1%) was higher than that of diploid control (59.4%) (P<0.05). Survival rate was 63.0% in triploid group (3n-1pb 62.0%, 3n-2pb 64.0%) and 62.0% in diploid group during the experimental period.

• Journal of Korea Foresty Energy
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• v.22 no.3
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• pp.20-28
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• 2003

This study was subjected to compare seasonal changes of survival rate, relative growth rate, and chlorophyll contents of major oak tree species including Quercus acctissima, Quercus mongolica, Quercus serrata, Quercus varibilis seedlings grown in Quercus acctissima forest under different light intensities. Three light intensities were 81% of sunlight, 34% of sunlight and 21% of sunlight. In each treatment, 100 tree seedlings were planted and survival rate, growth rate, and chlorophyll contents were measured. The highest survival rate was Quercus acctissima in 73% seedlings compared with those subjected to the other tree seedlings in 45~66%. Lowest survival rate was Quercus vnriabilis seedlings in 41%. Oaks tree species of the height, the root collar diameters of the relative growth were better in the seedlings grown in 81% light intensities of full sun. But growth rates decreased rapidly in the shade treatment of 21% light intensities of full sun. Lowest chlorophyll contents(chlorophyll a, b and total) were shown at 21% light intensities of full sun, lowest light intensity treatment in this study This result is thought growth and chlorophyll contents associated with light intensity Also, Physiological characteristics has to be investigated in near future because photosynthesis and chlorophyll contents were strongly related to tree growth with long periods.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.4
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• pp.467-473
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• 2016

Several of our recent studies have focused on mass production of the marine Cladoceran Diaphanosoma celebensis, which can serve as a feed substitute for Artemia nauplii in the culture of larval marine fish. We compared the growth and survival rates of tiger puffer Takifugu rubripes fed D. celebensis with those fed Artemia. The group fed D. celebensis showed an increase in growth from 0.10 g to 1.78 g, while the group fed enriched Artemia had a growth from 0.10 g to 0.92 g. The survival rate of fish fed D. celebensis was 86.7% while that of fish fed enriched Artemia was 51.1%, indicating that the former group was superior to the latter both in growth and survival rate. Fatty acid analysis revealed that D. celebensis fed Nannochloropsis oculata and Schizochytrium sp. had an eicosapentaenoic acid (EPA) content of 16.42% and a docosahexaenoic acid (DHA) content of 3.93%. Meanwhile, juvenile tiger puffer fed D. celebensis had an EPA content of 9.12% and a DHA content of 10.69%. Juvenile tiger puffer fed D. celebensis had a similar n-3 highly unsaturated fatty acid content to that of tiger puffer fed enriched Artemia which had an EPA content of 5.82% and a DHA content of 15.90%, indicating that no additional enrichment was required.

• Journal of Practical Agriculture & Fisheries Research
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• v.21 no.2
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• pp.49-58
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• 2019

This study aimed to determine of water quantity in pot for water flooding culture of Pinus thunbergii Parl., Chaenomeles japonica Lindl. ex Spach and Osmanthus fragrans Lour. The survival rate of P. thunbergii Parl. and C. japonica Lindl. ex Spach in the water quantity in pot 60% or 40% was 100% and the rate of O. fragrans Lour. in the 60% or 40% water was 90.0% or 93.3%. However the survival rate of the 100% water was less than 90% in P. thunbergii Parl, C. japonica Lindl. ex Spach and less than 60% was in O. fragrans Lour. The increasing rate of plant height for P. thunbergii Parl. in the water quantity in pot 40% or 60% was above 50%, and the C. japonica Lindl. ex Spach or O. fragrans Lour. was above 90%. However the increasing rate of plant height in the water 100% was less then the others as a 38.2%, 65.4% or 66.7% in respectively in P. thunbergii Parl., C. japonica Lindl. ex Spach and O. fragrans Lour. The increasing rate for leaf number for P. thunbergii Parl. in the water quantity 40% or 60% was above 80%, and the C. japonica Lindl. ex Spach or O. fragrans Lour. was above 70%, however the 100% water was below 60% in all treatment. Therefore, the survival rates in some woody plants of the 40% or 60% water in the pot was above 90% and the plant growth of plant height, plant width, leaf number or fresh weight was proper increased. But the survival rates and growth of the 100% water in the pot was decreased

• The Korean Journal of Malacology
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• v.24 no.2
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• pp.137-142
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• 2008

Growth and survival rates dependent on the density of a pen sell, Atrina pectinata were measured from Duekryang bay in Korea. Annual water temperature and salinity of the study area were ranged from 14.5 to $28.0^{\circ}C$ and from 27.98 to 31.89 psu, respectively. The pH, DO, COD, DIN, Chl-a and SPM in the study area ranged from 7.78-8.35 mg/L, 7.07-7.90 mg/L, 1.20-1.70 mg/L, 2.88-6.02 mg/L, 0.20-0.79 mg/L and 10.8-21.4 mg/L. The IL, COD and AVS in sediments ranged from 4.0-4.6%, 7.28-10.76 mg/L and 0.03-0.05 mg/L respectively. The daily growth rate of shell height and total weight were 0.27%, 0.33%(5 indiv./$m^2$), 0.26, 0.29%(10 indiv./$m^2$) and 0.21, 0.20%(35 indiv./$m^2$). The survival rate also decreased along the density gradient; highest at the lowest density of 5 indiv./$m^2$ and lowest at the maximum density of 35 indiv./$m^2$.

• Animal cells and systems
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• v.14 no.4
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• pp.291-296
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• 2010

Population ecological characteristics of growth and mortality play an important role in understanding the population dynamics of marine mammals. The instantaneous coefficients of natural and bycatch mortality were estimated for minke whales (Balaenoptera acutorostrata) in Korean waters using a population assessment model composed of bycatch and abundance data. The survivorship curve of this population was fitted to the data, and then the curve was revised using age-specific relative bycatchability coefficients ($q_t$). Instantaneous coefficients of natural and bycatch mortality of minke whales were estimated as 0.024/year and 0.076/year, respectively, and from this the survival rate was estimated as 0.905. This estimated survival rate was comparable to other cetaceans in other regions. The $q_t$ for this population ranged from 0.020 to 0.193. The revised survival rates were higher when the $q_t$ was taken into account. The mortality coefficient, survival rate, $q_t$ and survivorship curves had not previously been determined for minke whale in this area. This estimate could serve as fundamental information to assess the status of this population and for conservation and rational management.

• Journal of Ecology and Environment
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• v.44 no.1
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• pp.45-53
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• 2020

Background: The black soldier fly (Hermetia illucens) is gaining attention as an efficient decomposer of food waste. However, recalcitrant compounds such as plastics mixed into food waste may have negative effects on its growth and survival. Moreover, its efficiency of food waste degradation may also be affected by plastics. In addition, salt (NaCl) can also be present in high concentrations, which also reduces the efficiency of H. illucens-mediated food waste treatment. In this study, we assessed the growth of black soldier fly larvae (BSFL) reared on food waste containing polyethylene (PE) and polystyrene (PS) and NaCl. The weight of BSFL was measured every 2-4 days. Survival and substrate reduction rates and pupation ratio were determined at the end of the experiment. Results: The total larval weight of Hermetia illucens reared on food waste containing PS was greater than that of the control on days 20 and 24. However, the survival rate was lower in the group treated with 5% PS, as was substrate reduction in all PS-treated groups. The weight of BSFL reared on food waste containing PE was lower than that of the control on day 6. PE in food waste did not affect the survival rate, but the pupation ratio increased and substrate consumption decreased with increasing PE concentrations. Regardless of the plastic type, the addition of NaCl resulted in decreased larval weight and pupation ratio. Conclusions: Larval growth of black soldier fly was inhibited not by plastics but by substrate salinity. Additional safety assessments of larvae reared on food waste containing impurities are needed to enable wider application of BSFL in vermicomposting.