• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.5
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• pp.495-499
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• 2003

Age and growth of purpulish Washington clam (Saxidomus purpuratus) was investigated from 480 samples monthly collected from January to December 2002 in Jinhae Bay, Korea. Examination of outer margins of the shell revealed that the translucent zone was formed once a year from March to April, it can be used as annulus. Ages were determined from ring radius of shell, and maximum age of the the clam was 9 years. The spawning period was from May to October, and the main spawning occurred in July. The relationship between shell length (SL) and shell height (SH) was $SH=0.8405{\times}SL^{-4.9709}\;(R^2=0.97)$ and that between the shell length (SL) and total weight (TW) was $TW=0.9580{\times}10-4{\times}SL^{3.220}(R^2=0.97).$ The von Bertalanffy growth equation were $SL_t=125.57(1-e^{-0.2523(t+0.5367)},\;TW_t=549.26(1-e^{-0.2523(t+0.5367)})^{3.220}.$

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.5
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• pp.556-565
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• 2018

The age and growth of butter clams Saxidomus purpuratus were estimated using transmitted light on the shells of 364 samples from January 2017 to December 2017 in Jinhae Bay. Based on monthly variation in the marginal index (MI) of the shell, it is assumed that rings are formed once a year during the period from July to August in this species. The relationship between shell length (SL; mm) and shell height (SH; mm) was expressed by the equation SH=0.8053SL-2.9636 ($R^2=0.94$) and between SL and shell width (SW; mm) by the equation SW=0.5648SL-3.7105 ($R^2=0.90$). The relationship between SL and total weight (TW; g) was expressed by the following equation: $TW=0.00009SL^{3.2141}$ ($R^2=0.96$). von Bertalanffy's growth parameters were estimated using the regression wizard in the SigmaPlot computer program (Systat Software, Inc., v. 10.0). The maximum shell length ($SL_{\infty}$) was 126.16 mm, growth rate was 0.2030/year, theoretical age at shell length 0 ($t_0$) was -0.52 years, and asymptotic total weight ($TW_{\infty}$) was 509.17 g. Growth curves for SL and TW fitted to the von Bertalanffy's equation were expressed as follows: $SL_t=126.16(1-e^{-0.2030(t+0.52)})$, $TW_t=509.17(1-e^{-0.2030(t+0.52)})^{3.2141}$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.3 no.2
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• pp.103-109
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• 1970

The results of this work concerning the growth of the mussel, Mytilus edulis cultured by the hanging method in Koje Bay are as follows: The major spawning time is confined to the period from March to April. The mean growth of the mussel is indicated by the following formula; $$Y\;=\;1.508+0.659X-0.0559X^{2}+0.00367X^3$$ The major growing seasons are June and October The variance varied in proportion to the growth of the mussel, and each ranged, in shell height, from $1.25\~2.75\;to\;2.25\~4.25$ (mean:1.60 to 2.78)cm, $2.25\~5.25(3.00)cm,\;2.25\~7.75(4.83)cm,\;2.25\~7.75(5.05)cm\;and\;2.25\~8.25(5.95)cm$, and the variance were $0.278\~0.230$, 0.368, 0.701, 1.053 and 1.209, respectively. On the other hand, the variances differed in proportion to the growth of the mussel. The average length of the mussel life was about eighteen months. The mussels growing on the hanging line for arrestation undergo seasonal vicissitudes, and the mussels which fall off, mass into countless numbers during the period from August to October and finally disappear completely in November. The dimensions of the largest mussel are as follows: The shell height : 9.48cm The shell length: 4.49cm The shell breath : 3.55cm The shell weight : 22.05g The weight of the soft parts 19.25g The relative growth of the mussel is indicated as follows: Relationship between the shell height and the shell length: Y =0.486X+0.334 Relationship between the shell height and the shell breadth: Y = 0.359X+0.107 Relationship between the weight of the soft part and the shell weight: Y = 0.882X+0.901 Relationship between the shell height and the weight of the soft part: $$Y\;=\;0.02828X^{2.90518}$$

• 한국해양학회지
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• v.4 no.1
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• pp.36-48
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• 1969

The larvae of Mytilus coruscus were grown at the room temperature of approximately 15.1C under several different sulture conditions, i.e., salinity, population of the larvae, density and kind of food organisms, etc. (1) The egg of Mytilus coruscus obtained in the laboratory measured about 73.0${\mu}$ in diameter. The embryos gradually developed into larvae up to 179.0${\mu}$ shell length with the shell height of 135.9${\mu}$ even in the absence of the algal food. Beyond this size, however, the growth of larvae was considerably retarded, indicating that the better growth could be expected if the food began to be fed four days after spawning. (2) The larvae began settling upon reaching 281.4${\mu}$ to 310.9${\mu}$ in shell length or 264.3${\mu}$ to 301.9${\mu}$ in shell height. When the shell length reaches 322.6${\mu}$ to 337.1${\mu}$, the shell height also reaches about the same, i.e., 321.5${\mu}$ to 346.2${\mu}$. (3) Daily rate of food consumption was determined by the size of the larvae and the species of the algal food. Regardless of the species of food given, the rage of food consumption remained almost the same until the larva reached the straight-hinge stage, and marked variations were found as the larvae grew larger. Daily rate of food consumption was shown as follow; Chaetoceros calcitrans : Y=2.99167e$\^$0.000018243x$\^$2// Cyclotella nana : Y=3.00324e$\^$0.000015481x$\^$2// Monochrysis lutheri : Y=3.000056e$\^$0.000014485$\^$2// (4) Suitable amount of the food to be given was about five times of the consumed food by Mytilus coruscus. (5) When the numbers of the larvae was higher than ten per milliliter, the growth was significantly retarded. (6) Monochrysis lutheri and Cyclotella nana were much better than Chaetoceros calcitrans as the food of Mytilus coruscus, and even the same food organism showed some difference with the age of the organism. (7) Sea water of higher salinity showed the better result in the growth of the larvae and the water with the specific gravity of 1.020 or below was dangerous for the larvae. (8) The mean growth of the larvae of Mytilus coruscus under lavorable condition was shown as follows: shell length 121.8${\mu}$ to 179.0${\mu}$ : Y=119.18+7.42X 196.7${\mu}$ to 322.6${\mu}$ : Y=203.144+7.687X 322.6${\mu}$ to 985.1${\mu}$ : Y=302.5978+11.8356X shell height 86.3${\mu}$ to 135.9${\mu}$ : Y=86.22+6.40X 158.1${\mu}$ to 321.5${\mu}$ : Y=162.998+10.027X 321.5${\mu}$ to 1,215.4${\mu}$ : Y=309.3701+16.258X Relationships between the shell length and shell height were shown as follows: shell length 121.8${\mu}$ to 179.0 : Y=0.83726X-15.79165 196.7${\mu}$ to 322.6 : Y=1.29909X-100.58610 322.6${\mu}$ to 985.1${\mu}$ : Y=1.3536X-101.6806

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.30 no.3
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• pp.110-116
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• 2020

Grains in the BaTiO₃, which is used for a dielectric layer in MLCC(Multi-Layer Ceramic Capacitor) are necessary to form core/shell structure for a stable TCC(Temperature Coefficient of Capacitance) behavior. The shell property has been deduced from the whole TCC behavior of core/shell structure due to its tiny size, ~ few ㎛. This study demonstrates the individual TCC behavior of the shell phase measured by micro-contact measurement in a temperature range between 35 and 135℃. Pt electrode pairs deposited on an enlarged core/shell structure in a diffusion couple sample made the measurement possible. As a result, the DPT (Diffusion Phase Transition) behavior of the shell phase was revealed as a different TCC behavior from that of the core: a broad peak with T_m at 65℃. This would be also useful experimental data for a modelling that depicts dielectric-temperature behavior of core/shell structure.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.3
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• pp.223-230
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• 2010

To compare seed collection and the growth of Anadara subcrenata in Suncheon and Boseong Bays, environmental factors and the growth of larvae and spats were investigated from August 2008 to July 2009 in commercial farming sites in both bays. The variation in water temperature in both bays was similar, but the salinity was lower in Suncheon Bay than in Boseong Bay. The chlorophyll-a content was higher in Suncheon Bay due to the large inflow of freshwater. The density and shell length of A. subcrenata larvae did not differ significantly between the two bays. However, the relative growth of shell height to shell length was significantly higher in Suncheon Bay (P<0.05). The growth of A. subcrenata spats attached to a collector was significantly faster in Suncheon Bay (P<0.05). The spats in Suncheon and Boseong Bays grew to 24.3 and 21.0 mm in shell length, respectively, within 1 year after spawning, and the shell length reached 35.6 and 34.8 mm, respectively, within 2 years of spawning. The initial spats density was higher in Boseong Bay, but the growth of spats was better in Suncheon Bay. The faster growth of A. subcrenata in Suncheon Bay can be explained by the high chlorophyll-a content in this bay. Based on the low survival (%) and slower growth rate of spats in Boseong Bay, the commercial culture density of A. subcrenata in Boseong Bay should be reduced to the optimum level of the carrying capacity.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.6
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• pp.601-605
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• 2003

This study investigated the effect of dietary pigment sources on growth and shell color of juvenile abalone(Haliotis discus hannai). Three replicate groups of the abalone (average weight 173 mg) were fed diets containing various pigment sources such as Porphyra powder, Spirulina, yeast astaxanthin, and paprika extract for 16 weeks. Survival and weight gain were not affected by dietary pigment sources (P>0.05). Shell color of abalone fed diets containing Porphyra powder and Spirulina approached the yellow-red and orange, colors similar to wild abalone. However, shell color of abalone fed the diets containing yeast astaxanthin and paprika extract were similar to the bright green control group. These results should be useful for changing the shell color of abalone in aquaculture.

• The Korean Journal of Malacology
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• v.1 no.1
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• pp.13-18
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• 1985

The metamorphosis and the growth of larva in Limnoperna fortunei were studied from October, 1981 to December, 1983. 1) The larva of this species is observed in the three different stages in the form of D-shaped. The shell length of the larva in the early stage is $130.44{\mu}m$ to $143.60{\mu}m$ and in the middle stage $161.67{\mu}m$ to $184.11{\mu}m$. In the late stage the length size of the larva increases up to $194.55{\mu}m$ to $208.45{\mu}m$. The shell height is $103.19{\mu}m$, to $119.47{\mu}m$, $126.51{\mu}m$ to $157.63{\mu}m$ and $136.87{\mu}m$ to $176.35{\mu}m$ in the three stages respectively. Thus the growth ratio of shell length to shell height is 1:0.75. 2) The metamorphosing stage begins when the shell height becomes larger than $210{\mu}m$ and the shell length exceedes $260{\mu}m$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.13 no.4
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• pp.207-212
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• 1980

Growth rates of oysters at four oyster farms in Hansan-Geoje Bay, near Chungmu, southern Korea, and density-dependent relative shell growth were investigated from November 1979 to May 1980 with the following results: The oysters at Sorang farm showed the best growth, the shell height in May 1980 attaining 10.10 cm, at Hwado 8.69cm and Songdo 8.57cm, all of which started growing in June 1979. At Chubong the oysters which started growing in July attained 8.6cm. The best grown oysters at Sorang shelved relatively slow growth in meat weight until February 1980, and then showed rapid growth upto May. At Hwado and Songdo they grew fast from December 1979 to February 1950, and from April to May 1980. Those at Chubong gradually increased growth rate from December 1979, and in April and May they showed rapid growth but still being smaller than the others. The ratio of meat weight to shell weight increased at Whado, Songdo and Chuhong after December 1979, but at Sorang it increased rapidly after February 1980. The ratio of shell length to shell height was 0.60 and up when the individual number of oysters attached to each cultch-disc(oyster shell) was less than 13, 0.56 to 0.60 when 14 to 25, and 0.51 or less when over 28, respectively.

• Korean Journal of Agricultural Science
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• v.49 no.3
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• pp.547-560
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• 2022

The present study investigated the effects of dietary supplementation of peanut shell extract on the growth performance and physiological properties of broiler chicks. Two diet energy levels (Positive and Negative) and four additives (0.0, 0.05, and 0.1% peanut shell extract and commercial antioxidant) were factorially arranged for eight treatments. The overall weight gain of the broilers was slightly improved at 0.05% for the antioxidant treatments regardless of the diet energy levels, but there was no statistical difference among the treatments (p > 0.05). The carcass characteristics of the broilers, such as cooking loss, crude protein content, antioxidant activity, and thiobarbituric acid reactive substances (TBARS) values, were improved by the feeding diets containing the 0.05% peanut shell extract. Furthermore, it was confirmed that the dietary supplementation of peanut shell extract did not have a negative effect on the immune responses of the broilers show by the lack of statistical differences in the liver and bursa Fabricious weight and cytokine level among the treatments. From the economic analysis, dietary supplementation of peanut shell extract significantly influenced the compensatory growth and food efficiency and, in turn, led to a decrease in the duration needed to reach 1.5 kg compared to the control. These results suggest the possibility that the peanut shell extract could be used as a functional feed additive by improving the growth performance and carcass characteristics with no detrimental effects on broilers.