• Journal of Aquaculture
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• v.10 no.2
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• pp.97-103
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• 1997

Larval growth of the oyster, Crassostrea nippona, was investigated at the different conditions such as water volume, depth of culture vessel and initiative feeding time at $23^{\circ}C$. As a result, morphological changes were occurred during the early larval growth. That is, shell length was higher than shell height at the time of D-shaped larvae. Later, the length became equal to the hight when their shell length reached $127\mum$and then shell height increased rapidly. Some of pediveliger larvae with the size of $360\mum\;in\;shell\;length\;and\;385\mum$ in shell height began to temporarily settle on the substrate after 18 days. The result also indicated that the depth of culture vessel turned out to be an important factor rather than water volume for the larval growth. The fist feeding time of oyster larvae appeared to be the first day after fertilization.

• Korean Journal of Environmental Biology
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• v.20 no.4
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• pp.378-385
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• 2002

Growth of Pacific oystey, Crassostrea gigas, in Kamak Bay, Korea was modeled using Von Bertalanffy growth function, seasonal Von Bertalanffy growth function and generalized growth equation of Schnute and Richards' growth model, based on shell length and wet weight frequency data of 9208 oysters. Carrying capacity in the oyster culture ground was also estimated using Schaefer's and Fox's surplus production model. The present results suggest that the generalized growth equation of Schnute and Richards' model is fitter to describe the length growth pattern of C. gigas than Von Bertalanffy growth functions. This results also suggest that the current number of culture facility per unit area in 2000 is similar to the number of facility that produces the maximum production of oyster per unit area.

• Korean Journal of Organic Agriculture
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• v.17 no.1
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• pp.55-62
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• 2009

In this paper, we assessed the growth of rice seedlings(Chucheong variety) in commercial organic growth medium that was substituted with different ratios of vermicast of oyster mushroom waste grown under potting alone, and potting and floor layering treatment. The commercial organic growth medium was substituted with vermicast at ratios of control, 2%, 4% and 6%, respectively. The control consisted of commercial organic growth medium alone without vermicast. Incorporation of $4%{\sim}6%$ vermicast of oyster mushroom waste into a commercial organic growth medium enhanced the growth of rice seedlings significantly as compared to commercial organic growth medium alone(control), and 2% amended with vermicast in potting treatment. This results demonstrate that substitution with low ratios of vermicast($4%{\sim}6%$) will promote growth of rice seedlings. The growth of rice seedlings in commercial organic growth medium alone without vermicast was enhanced significantly as compared to the substituted with vermicast in floor layering treatment, it may due to nutrient uptake by elongated root from the vermicast when applied to on the floor layering. Floor layering treatment is an effective method for potting processing of vermicast. The vermicast of oyster mushroom waste should have a high safety and great potential as materials of growth media for increasing plant growth, either as soil conditioner, or as substitution or amendments to commercial organic growth medium. For the enhanced growth of rice seedlings, demand to increase with total nitrogen, and decrease with the carbon and nitrogen ratio(C/N) of commercial organic growth medium supplied by such as vermicast.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.1 no.2
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• pp.105-113
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• 1968

The following experiments were carried out at rock method oyster field at Uduri, Dolsan-myon, Yeocheon-gun, Jeon-nam, Korea, in 1966. In this experiment, the settling rate of oyster at each exposure level and their growth rate were checked. 1. The settling rate of oyster spats was highest at 4 hour exposure level in the day-time during spring tide, and the growth rate became greater the lower stratum until 3 hours and 30 minutes exposure level. 2. Rocks applied at the place higher than 5 to 6 hour exposure level which amount 26 percents of applied rocks, were not utilized properly because the settling rate of spats and their growth rate were very bad. 3. For the future application of rocks for oyster culture, effort should be paid to instruct the oyster farmers to apply all rocks at proper exposure Ie el with bottom leveling and the rocks should be spaced properly for better barvest.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.3
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• pp.259-266
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• 2011

To produce cupped oyster sprat consistently, we investigated the efficiency of nine settlement substrates using selective breeding of Pacific oyster Crassostrea gigas, with the goal of popularizing off-bottom culture on the west coast of Korea. We also compared the growth and survival of selectively bred sprat (diploid) with triploid sprat from an off-bottom culture system. Considering, the attachment rate and detachment efficiency, producing cupped oyster in a polypropylene gunny bag proved to be the most effective method. There were no differences in shell growth or total weight between the diploids from selective breeding and triploids from off-bottom culture for 5 months. However, the survival rate was 8 times higher in the diploids than the triploids. Transplanting sprat from selective breeding is one way to restore oyster farms and nurture off-bottom culture along the west coast.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.5
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• pp.489-494
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• 2010

The nutritional demand of oyster larva (Crassostrea gigas) were investigated to determine the optimal culture conditions and improve micro-algae utilization. Changes in nutrients and shell growth were examined in fed and 96-h (48 h in late umbone stage) oysters at four larval stages. Shell growth increased significantly in D shape larvae, regardless of feeding variations. No growth was observed in starved larvae, except in shell length of umbone (to 11.9 ${\mu}m$). Fed larvae showed significant growth in all development stages (P < 0.05). During starvation, lipids were most significantly decreased in all larval stages (by 76.8%, 68.3%, 76.3%, and 40.3%, respectively), followed by protein (41.1%, 31.1%, 33.1%, 16.7%) and nitrogen-free extracts (40.8%, 24.3%, 36.9%, 20.1%), Gross energy (kcal/g) consumption in each larval stage was 49.6%, 35.1%, 39.1%, and 20.4%, respectively. Our results indicate that lipids are the most important energy source during the early larval development stages of C. gigas.

• Environmental Analysis Health and Toxicology
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• v.25 no.2
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• pp.161-168
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• 2010

The observed the toxic effect of WSF (Water Soluble Fraction) on development time, development rate, attachment rate, survival rate and growth of the larva during the early stage of the Pacific oyster, Crassostrea gigas. The time required early juvenile from the fertilized eggs exposed to crude oil (WSF) was about 13 hours in control group. But that of the crude oil dose group takes 12 hours, with shorter compared to control group. Development and attachment rate of the oyster significantly higher in 0.4 and 0.8 mg/L WSF compared to control group (P<0.05) but significantly lower more than 1.6 mg/L WSF (P<0.05). Survival rate of the oyster larva significantly higher in 0.4 and 0.8 mg/L WSF compared to control group (P<0.05) but significantly lower more than 2.4 mg/L WSF (P<0.05). Survival rate of spot showed no significantly difference compared to control group (P>0.05). Shell growth of the oyster were significantly lower more than 1.6 mg/L WSF compared control group (P<0.05). The effect concentration of crude oil showed that more 0.4 mg/L in development and attachment rate and more 1.6 mg/L in growth. Also, chronic exposure of crude oil even effect also in low concentration.

• Journal of Mushroom
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• v.5 no.2
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• pp.65-70
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• 2007

This study was carried out to find out respiration characteristics of new variety of oyster mushroom to the temperature response. In new species of oyster mushroom, the account of respiration was on the increase when the growth temperature with the passage of growth stage was on the rise. The $CO_2$ concentration was accelerated as increasing the growth temperature, whereas the $O_2$ concentration was decreased. The account of respiration of new variety was in the descending order, Hukbaek>Jinmi>Chungpung>Suhan2>Chunchu2. Also, the ventilation exponent at $15^{\circ}C$ was Suhan2 2 ~12%, Chungpung 9~24%, Jinmi 15~37%, Hukbaek 17~39% in proportion to Chunchu2. The experiments related to respiration characteristics of new variety of oyster mushroom were worthy of recommending to new variety cultivator.

• Food Science and Preservation
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• v.9 no.1
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• pp.56-60
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• 2002

Physiological functions of oyster mushroom Kimchi were investigated. Oyster mushroom Kimhies were found to have antioxidant activities. The effect was in a dose-dependent manner, the effect was higher in oyster mushroom Kimchies than in control and higher in raw oyster mushroom Kimchi (ROMK) than in blanched oyster mushroom Kimchi (BOMK). Methanol extract of Kimchi revealed antimutagenic activity and suppressed growth of cancer cell in a dose-dependent manner, and the effects were higher in ROMK than in other Kimchies. The methanol extracts of oyster mushroom Kimchi alone did not appear proliferation effect of spleenic immune cell, but revealed the effect with Con A. The proliferation effect was higher in ROMK than in BOMK.

• Fisheries and Aquatic Sciences
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• v.12 no.2
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• pp.111-117
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• 2009

To develop sustainable management strategies for oyster farms in Pukman Bay, Korea, we estimated primary production using a numerical model. Because oysters are filter feeders, estimations of primary production (PP) are essential in developing management strategies. The daily PP ranged from 0.07 to 1.5 gC/$m^2$/d and showed significant spatial variations. The spatial distribution of PP was strongly associated with hydrodynamic features, and distinct patterns were observed in three different regions. In the inner bay, high PP was directly influenced by urban and agricultural sewage. The middle part of the bay had low PP, whereas PP in the outer area was high. PP was relatively low during the main oyster growth season, from late autumn to early winter. These findings represent important information for developing a management model for oyster farms in Pukman Bay.