• The Korean Journal of Ecology
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• v.1 no.2
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• pp.49-56
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• 1977

For the culture the population growth, shell length and spawning seasons of Gomphina veneriformis, and its environmental factors, were investigated at the Jeju coastal regions. from Feburuary, 1975 to March, 1976. The soil movements of the tidal flats where the clams inhabited were relatively rapid during the strong tidal actions. The rate of population growth were rapid from April to September, then became obsure. The relative growth equations of the shell height (SH) and the shell breadth (SB) against the shell length (SL) of the clams were as follows: Changhung : SH=0.751 SL + 0.685, SB=0.448 SL-0.630 Pyoson : SH-0.775 SL - 0.115, SB=0.464 SL-1.008 Hwhason : SH=0.794 SL - 0.923, SB=0.485 SL-1.155 Kwhagzee : SH=0.771 SL - 0.644, SB=0.455 SL-1.049 The meat weight increases of the clams were continued from March to late June, then it decreased sharply up to late August. The spawning of the clams seems to be late from June to Spetember in the regions studied.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.4
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• pp.375-379
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• 1986

A culture experiment of the ark shell, Anadara broughtonii, one of the edible clams, was carried out in Yoja Bay located at the south ern coast of Korea to find the state of growth and any problems which influence them. Seed shells at an average length of 2.5cm and a weight of 2.5g were planted on bottom mud with a density 20 to 40 shells per square meter on March 10 and 11, 1982. Shell length, shell height, shell breadth, meat weight (wet weight), and total weight for six months from August 1982 to February 1983 were measured to find their state of growth. At the same time, the survival rate was investigated during the whole culture period through December 1983 when they were harvested. Growth, on the whole, was fast when water temperature was high. For a year, an average shell length and total weight attained to 6.1 cm and 63.0g respectively and meat weight was gained to 19.5g. It showed that the state of growth was favourable. Shell shape became round from the oval ana meat weight increase was faster than shell growth as time goes by regardless of water temperature while both shells and total weight increased faster during high temperature. A month after seed shells were planted, about $30\%$ of them was dead and a high mortality, say $5\%\;to\;8\%$ per month, was kept till September. It dropped to around $2\%$ aften divers eliminated starfish, Asterias spp., in August. Thereafter, the rate maintained through December. In all, the final survival rate was about $10\%$ at the time of harvest in December 1983. It was caused mainly by starfish predation. Therefore, a best way for satisifactory culture is seemed to find a way to get rid of the starfish.

• The Korean Journal of Malacology
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• v.14 no.2
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• pp.121-130
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• 1998

Studies on the distribution and growth of the mud mussel, Musculista senhousia, were carried out in the mud-tidal flat near Mokpo from August 1996 to July 1997. The patch distribution of the mussel was observed in the middle part of the tidalflat during the study period. Annual mean density was 8,215${\pm}$1,394 ind./m2 and annual mean biomass was 1,966.43${\pm}$668.49 g TWwt/m2 in total wet weight, 760.04${\pm}$279.13 gMWwt/m2 in meat wet weight, 209.93 ${\pm}$ 49.41 gMDwt/m2 in meat dry weight, and 109.66${\pm}$58.78 gAFDW/m2 in ash-free dry weight. The monthly mean size of shell length varied from 11.00 mm to 16.97 mm. Relationship between shell length (SL) and shell height (SH) showed a positively significant regression (SH=0.482SL+0.791, R2=0.940, P<0.001). Regressions of total wet weight (TWwt) (TWwt=7.601${\times}$10-5SL3.052, R2=0.905, P<0.001), and meat wet weight (MWwt) (MWwt=1.127${\times}$10-5${\times}$SL3.404, R2=0.784, P<0.001) on shell length were positively allometric, with highly significant correlation coefficient. The relationships between SL and meat dry weight (MDwt), and AFDW were MDwt=9.813${\times}$10-6${\times}$SL2.928 (R2=0.421), and AFDW=1.015${\times}$10-5${\times}$SL2.922(R2=0.810), respectively. The condition factor of the mussel has been increased from March and formed a peak in July and August. It was sharply dropped in September. These results suggest that the gonadal development of the species commenced to be occurred in spring and that main spawning occurred between August and September.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.13 no.4
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• pp.179-183
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• 1980

The efficiency of energy transfer by a population of the farmed pacific oyster, Crassostrea gigas was studied during culture period of 10 months July 1979-April 1980, in Geoje-Hansan Bay near Chungmu City. Energy use by the farmed oyster population was calculated from estimates of half-a-month unit age specific natural mortality rate and data on growth, gonad output, shell organic matter production and respiration. Total mortality during the culture period was estimated approximate $36\%$ from data on survivor individual number per cluster. Growth may be dual consisted of a curved line during the first half culture period (July-November) and a linear line in the later half period (December-April). The first half growth was approximated by the von Bertalanffy growth model; shell height, $SH=6.33\;(1-e^{0.2421(t+0.54)})$, where t is age in half-a-month unit. In the later half growth period shell height was related to t by SH=4.44+0.14t. Dry meat weight (DW) was related to shell height by log $DW=-2.2907+2.589{\cdot}log\;SH,\;(2, and/or log $DW=-5.8153+7.208{\cdot}log\;SH,\;(5. Size specific gonad output (G) as calculated by condition index of before and after the spawning season, was related to shell height by $G=0.0145+(3.95\times10^{-3}{\times}SH^{2.9861})$. Shell organic matter production (SO) was related to shell height by log $SO=-3.1884+2.527{\cdot}1og\;SH$. Size and temperature specific respiration rate (R) as determined in biotron system with controlled temperature, was related to dry meat weight and temperature (T) by log $R=(0.386T-0.5381)+(0.6409-0.0083T){\cdot}log\;DW$. The energy used in metabolism was calculated from size, temperature specific respiration and data on body composition. The calorie contents of oyster meat were estimated by bomb calorimetry based on nitrogen correction. The assimilation efficiency of the oyster estimated directly by a insoluble crude silicate method gave $55.5\%$. From the information presently available by other workers, the assimilation efficiency ranges between $40\%\;and\;70\%$. Twenty seven point four percent of the filtered food material expressed by energy value for oyster population was estimated to have been rejected as pseudofaeces : $17.2\%$ was passed as faeces; $35.04\%$ was respired and lost as heat; $0.38\%$ was bounded up in shell organics; $2.74\%$ was released as gonad output, $2.06\%$ was fell as meat reducing by mortality. The remaining $15.28\%$ was used as meat production. The net efficiency of energy transfer from assimilation to meat production (yield/assimilation) of a farm population of the oyster was estimated to be $28\%$ during culture period July 1979-April 1980. The gross efficiency of energy transfer from ingestion to meat production (yield/food filtered) is probably between $11\%\;and\;20\%$.

• 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 Fisheries and Aquatic Sciences
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• v.14 no.4
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• pp.221-226
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• 1981

The seedlings of the scallop, Patinopecten yessoensis, which were collected in April 1980, April 1981 and May 1981, and the grown-up scallops collected in the sea bottom in November 1979, were reared by hanging method up to the July 1981. The growth of the seedlings collected in April 1980 was greatly affected by the time of the seedling collection, manipulation of the net cage, density in the net cage and the annual water temperature fluctuation. The scallops reared from the spat collected in April 1980 reached the sizes of 0.33 mm, 1.23 mm, 29.34 mm and 59.59 mm in shell length in 40,75, 285 and 450 days respectively. Since then, growth rate was determined as follows based on the age estimated by the year rings on the shell:84.96mm in 19 months, 99.3mm in 31, 112.3mm in 37 and 113.64mm in 43 months. The meat and the adductor muscle weight increased with the shell length. The meat weight roached about 15g when the shell length was 60-70mm and about 94.13 g when 130-140mm, and the adductor muscle weight reached about 4.89 g when the shell length was 60-70 mm and about 39.59g when 120-130 mm. But the growths of the meat and the adductor muscle weight were in stagnancy after scallops reached 125 mm in shell length.

• The Korean Journal of Malacology
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• v.29 no.1
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• pp.43-50
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• 2013

We investigated the growth performance of oysters (initial shell height $57.5{\pm}8.5$ mm) under differing conditions of tidal exposure time and culture rack height in an experiment that commenced in April, 2011. Significant differences were observed in shell height from June 2011, in total weight from August, and in meat weight from September. Fatness tended to decrease during the experimental period, but was not significantly different at the end of the experiment. Significant differences in survival rates were mainly observed from June to August. After September, further changes were not observed in any experimental treatment group. The greatest growth potential ($L_{\infty}$) and survival rate were observed at a sea level of approximately 116 cm. The results indicate that in the study area the use of oyster culture conditions involving 1 or 2 h of tidal exposure and 60 - 70 cm rack height could result in oysters reaching the favored commercial half shell size within 14 months, with > 80% survival.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.2
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• pp.105-115
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• 2004

Growth pattern of the soft clam (Mya arenaria oonogei) was estimated based on samples collected from the Yeongsan River estuary on the southwest coast of Korea between August 1996 and September 1997. Mean density of the clam during study period was $55\;ind./m^2$ and varied monthly from 281 to $8\;ind./m^2.$ The clams from the study area ranged in age from one year to seven years, with shell lengths between 40.4 mm and 104.1 mm and biomass between 8.4 and 152.3 g in total wet weight. The spawing season was estimated to occur between September and October based upon a reduced fatness index, an indication of spawning, during these months. Burial depths increased with growth of the clams and most were found buried between 10 and 20 cm in the sediments. Significant relationships were found between shell length and shell height (SH), total wet weight, (TWt), meat wet weight (MWt), meat dry weight (DWt), ash free dry weight (AFDW) and burial depth. The von Bertalanffy growth equations of the clams were $L_t(mm)=138.98(1-e^{-0.1325(t+0.8853)})\;and\;W_t\;(gTWt)=325.93\;(1-e^{0.1325(t+0.8853)})^{2.6982}.$ These equations suggest that in their first year the clams should reach 31 mm in length with a biomass of 5.7 g in total wet weight.

• 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.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.8
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• pp.1136-1141
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• 2011

Effect of dietary essential oils on growth, feed utilization and meat yields of white leg shrimp L. vannamei was investigated. White shrimp fry weighing 0.62 g were kept in one of 12 tanks (75 head/500 L holding tank) in a closed recirculation system. Four experimental diets, a commercial diet (control), phytoncide oil (PO), oregano oil (OO) and fermented garlic liquid (GL) were fed for 16 weeks. The mean water quality values for the whole experimental period were $27.8{\pm}1^{\circ}C$, $7.6{\pm}0.3$, $15.5{\pm}0.3$ g/L and $6.1{\pm}0.3$ mg/L for water temperature, pH, salinity and dissolved oxygen, respectively. At the end of the trial, 10 shrimp per tank were randomly sampled and meat yields (%) were evaluated after peeling the shell and removing the head. After a 16 week feeding trial, final weight of shrimp ranged from 21.9 g to 23.6 g. Feed conversion was not significantly different among groups (p>0.05), which was the lowest (1.95) in the control and highest (2.30) in the PO. Specific growth rate was also not significantly different (p>0.05) and ranged from 3.18% to 3.25%. Average daily gain of 0.2 g was obtained in all treatments. Mortality varied from 35.1% for control to 44.9% for OO. Meat yields maintained constant at 52.1% for control to 53.0% for PO. The study suggested that natural essential oils could not exert any improvement in growth performance, mortality and meat yields of white leg shrimp.