• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.4
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• pp.287-294
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• 2004

Effect of growth and survival rate on different densities in the cage culture of juvenile abalone (Haliotis discus hannai) were determined in Myoduri Yeosu, Jeollanamdo from April 2000 to April 2001. The shell length growth was conducted using $32.35{\pm}1.35$ mm abalone juveniles for 374 days at densities $15{\%}\;(230\;indv./m^{2}),\;30{\%}\;(460\;indv./m^{2}),\;45{\%}\;(690 \;indv./m^{2}),\;60{\%}\;(920\;indv./m^{2})$. The result showed that the hightest growth rate was observed in lowest $(15{\%})$ density experimental group. Survival rate of Juvenile abalone was the highest in $15{\%}$\; density group and lowest in $45{\%}$ density group and distribution rate of shell length showed the highest as $30{\%}\;in\;230\;indv./m^{2}\;(15{\%})$ group.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.3
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• pp.243-250
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• 2011

The effects of food, temperature, salinity, and rearing density on the survival and growth of the swimming crab Portunus trituberculatus, were studied. With regard to food, the larval survival rate to zoea IV was the highest (53.9%) in the mixed feed group (rotifers+ Artemia), followed, in order, by the rotifer, commercial feed, and Artemia groups. The growth of young crabs reared on different diets was the highest in group VI. The survival rate to zoea II at 20 to $30^{\circ}C$ ranged between 77.2% and 83.1%, and was the highest for crab I (17.3%) at $25^{\circ}C$. When young crabs were cultured individually at four different temperatures (20, 25, 30, and $35^{\circ}C$), the growth did not differ significantly at 25 to $30^{\circ}C$, but was higher than at $20^{\circ}C$. The survival rate of larvae to crab I was 12.7 and 11.4% at 25 and 28 psu, respectively, while all of the larvae died at 15 psu. For young crabs, there was no significant difference in growth and survival from 20 to 30 psu. The survival rate decreased with increasing rearing density from zoea I to crab I. Each molting cycle took 1 month from crab I to VIII. Subsequently, the interval increased with growth. The mean body weight of crab XV after 24 months was $428.05{\pm}57.63\;g$.

• Plant Resources
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• v.1 no.1
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• pp.38-42
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• 1998

One of the most attractive short-term possibilities for increasing freezing tolerance of winter crops may be the application of chemicals. This research was conducted to determine the effect of two plant growth regulators. Terpal-C and Cerone on freezing tolerance and winter survival of canola. Three cultivars were planted on the michigan state University Agronimy Farm at East Lansing. MI. on Sept. 10. 1992 and 1993 Chemicals were applied to one-month-old plants when they reached the 5 leaf stage. Ion leakage tests for freezing tolerance were conducted before and after chemical treatment. Winter survival was evaluated by counting the plant standing in the fall and spring. Neither of the chemicals. Terpal-C. inhibited natural cold hardening.

• Korean Journal of Environment and Ecology
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• v.29 no.4
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• pp.533-538
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• 2015

This study was conducted to examine the effect of salinity on the early embryonic development stage of boreal digging frogs (Kaloula borealis). An experiment was carried out with the eggs of K. borealis mating couples laid along the coastal zone of Jeju Island in June 2013. The salinity was set to 0, 1, 3, 5, and 7 ‰, respectively. The survival and growth of the larvae at various stages from the egg phase to the closing of their external gills phase were observed. In another experiment, tadpoles in internal gill stage were placed in solutions with salinity of 0, 1, 3, 5, and 7 ‰, respectively, and their survival rate and growth rate were observed, and then the results of the two experiments above were compared. The results showed that in egg and external gill stage, there was no significant difference in survival rate in 3 ‰ solution, though there was low survival rate in 5 ‰ solution. Further, all the eggs were dead in 7 ‰ solution, so it appeared that solutions with salinity of 5 ‰ or higher affect the survival of K. borealis in the early embryonic development. Larvae in the internal gill stage showed no significant difference in survival rate from the control group up to a salinity of 5 ‰, but when placed in a solution of over 7 ‰ salinity, the survival rate decreased. The growth rate also slowed down with the higher salinity. It appeared that in both the external gill stage and the internal gill stage in 5 ‰ solution, the growth rate decreased significantly compared to the control group. From this study it is concluded that higher salinity values have a significant impact on the survival and growth of the K. borealis larvae and this finding can be used to conserve K. borealis species that are decreasing in number due to the side effects of development in coastal areas.

• Korean Journal of Agricultural Science
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• v.51 no.1
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• pp.25-39
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• 2024

This study aimed to determine a method for restoring grasslands to forests in mountainous areas. The study was conducted in an area damaged by trampling due to construction activity and herding. Additionally, there were concerns of hindered tree growth due to the alpine region climate, characterized by the low temperatures, drying, and strong winds. Therefore, forest restoration treatments such as tillage, furrow, and shading were performed to improve growth conditions. From July 2021 to April 2023, soil temperature and moisture were monitored for each treatment plot, and changes in the initial growth and survival rate of Abies holophylla were investigated. Both soil temperature and soil moisture showed significantly higher values during the four seasons in the grassland-furrow treatment plot (p < 0.05). Compared to the grassland-control plot, the average soil temperature in winter was as high as 1.1℃, and the soil moisture in summer was as high as 20.3%. Additionally, the survival rate and relative growth rate were the largest in the grassland-furrow treatment plot. The survival rate was 87.5%, the relative growth rate in terms of height was 0.013, and the relative growth rate in terms of diameter at root collar was 0.023, indicating that furrow treatment had a positive effect on the initial survival and growth of seedlings. These results suggest that furrow treatment may be an appropriate restoration method when implementing forest restoration projects in areas where tree growth is challenged.

• Journal of Aquaculture
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• v.14 no.1
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• pp.29-33
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• 2001

Total length and body weight of grey mullet were 6.4cm and 2.1g, respectively at the beginning of the experiment. After 60 days of rearing, body weight of the mullet(363%) was significantly higher in freshwater group than that (187%) in seawater group. However, the condition factor showed no significant differences between seawater (9.0%) and freshwater (8.8%) groups. Survival of the mullet was 98.3% and 64.3% in seawater and freshwater groups, respectively.

• Journal of Practical Agriculture & Fisheries Research
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• v.20 no.1
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• pp.97-105
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• 2018

We assessed the effects of population density on the growth and survival rate of sea cucumber(Stichopus japonicus) in indoor tank Growth of S. japonicus in high density breeding was slow overall, and body weight on 250, 350 and 500 individual/m² group were 31.9g, 26.8g and 21.5g, respectively. The growth rate of body weight was 3.5~5.1 times according to the density of water, and the survival rate was 44.2~50.1%. The growth and survival rate were increased as decreasing the storage density. During the breeding season, small individuals tend not to be large and constantly culled, so it is necessary to set up the sorting period (etc.), and divide S. japonicus into groups of similar size.

• Korean Journal of Environmental Biology
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• v.30 no.1
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• pp.9-14
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• 2012

The gobiidae, $Tridentiger$ $trigonocephalus$, $Chasmichtthys$ $dolichognathus$ and $Favonigobius$ $gymnauchen$ were reared for 4 weeks under 0~33.6‰ salinity conditions to examine the effects of various salinity on its survival and growth. Survival rate of $C.$ $dolichognathus$ and $F.$ $gymnauchen$ were significantly declined below 3.4‰ and 0‰, respectively. Growth rate of $T.$ $trigonocephalus$ was significantly reduced 0‰ salinity. Growth rate of $C.$ $dolichognathus$ and $F.$ $gymnauchen$ exposed to ${\geq}$13.4‰ and ${\geq}$6.7‰ were significantly higher than those of gobiidae exposed to below ${\leq}$10.1‰ and ${\leq}$3.4‰ salinity, respectively. This study reveled that low salinity (${\leq}$3.4‰) reduced survival and growth rates of the 3 gobiidae suggesting potential influence on the natural mortality of gobiidae in the coastal areas.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.10
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• pp.1477-1482
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• 2001

Research in low cost feeds with high nutritional value and immunogenicity is important to reduce production cost and increase yields in the shrimp industry. In this study, immunostimulants of bacterial origin (peptidoglycan and lipopolysaccharides) and egg white were incorporated in shrimp diets as feed additives to determine the growth, survival and tolerance of Penaeus monodon to white spot syndrome virus (WSSV). Although the results obtained were not statistically significant (p>0.05) among the treatments, shrimp fed with bacterial additives and egg white showed higher weight gain, specific growth rate and survival than those fed on commercial shrimp diet. Shrimp fed with artificial diet showed 100% mortality when challenged with WSSV. However, shrimp fed on peptidoglycan supplemented diet had higher survival than their counterpart, whereas shrimp fed on egg white supplemented diet had a higher specific growth rate and better tolerance when challenged with WSSV. Further studies are required to determine the effectiveness and optimization of bacterial strains and egg white as feed additives to increase production and enhance the shrimp immune response to diseases.

• The Korean Journal of Malacology
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• v.28 no.4
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• pp.293-303
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• 2012

Growth and survival (%) of the larvae and spats of Scapharca broughtonii fed on three different microalgal species (Isochrysis galbana, Pavlova lutheri and Chaetoceros simplex) were investigated with the analysis of fatty acid composition. The larvae fed on mixed diet with three microalgal species showed the highest growth in shell length ($261.3{\pm}13.5{\mu}m$) and survival ($27.4{\pm}5.3%$). The growth and survival (%) of the larvae fed on the single diet with C. simplex were significantly higher than those of the larvae fed on I. galbana or P. lutheri (P < 0.05). The growth and survival (%) of S. broughtonii spats reared for 30 days were also highest in the mixed diet group with $1,114.8{\pm}128.0{\mu}m$ and $61.3{\pm}5.5%$, respectively, and followed by C. simplex, I. galbana and P. lutheri. With respect to composition of fatty acid of the single or mixed microalgal diet, the content of PUFA and n-3 HUFA were the highest in C. simplex. This result can be considered as the reason for high growth and survival (%) of the larvae and the spats. C. simplex was the best species as the single diet, but the mixed diet with three microalgal species showed better dietary value than single diet did for the larvae and spat of S. broughtonii.