• Title/Summary/Keyword: natural science

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Salinity Tolerance of Eggs and Juveniles of Flounder, Paralichthys olivaceus (Temminck et Schlegel) (넙치, Paralichthys olivaceus (Temminck et Schlegel) 난 및 자치어의 염분 내성에 관한 연구)

  • CHUN Je-Cheon;RHo Sum
    • Journal of Aquaculture
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    • v.4 no.2
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    • pp.73-84
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    • 1991
  • Underground sea water is widely utilized for land based aquaculture in Cheju province, Korea nowadays. Salinity of this water($20{\~}30$ ppt) is slightly lower than natural sea water but because of its good water quality and temperature which is maintained at $16{\~}18^{\circ}C$ all year-round, many fish farmers are using this water for finfish culture. To evaluate the possibility of utilizing underground sea water for the seed production of the flounder, Paralichthys olivaeceus, hatching rate of fertilized eggs, survival rate of hatched larvae, and growth rate of the juveniles were tested with various salinity levels ranged from 14.1 ppt to 40.2 ppt. The salinity ranges which showed over $70{\%}$ survival rate for fertilized eggs to hatchout were 33.7 ppt${\~}$40.2 ppt, for hatched larvae to 2-day-old were 20.6 ppt${\~}$40.2 ppt, from 10-day-old to 12-day-old were 27.2 ppt${\~}$40.2 ppt, and from 45-day-old to 47-day-old were 20.6 ppt${\~}$40.2 ppt. Two hundred day old fingerlings showed no mortality when exposured to 7.6 ppt${\~}$40.2 ppt for 2 days. All fish died within 3 days when 45-day-old juveniles were transferred directly from normal sea water to 14.1 ppt sea water. However, they were all survived when transferred first to 20.6 ppt for 3 days then to 14.1 ppt sea water. The highest growth rates of fingerlings reared at 4 different salinities (33.7, 27.0, 31.0, or 15 ppt) were obtained at the 27 ppt group followed by 33.7, 21.0, 15 ppt respectively. The relationship between the days of rearing (X) and the total length of the fingerlings were as follows. $33.7\%$ group : Y=8.8109 + 0.1104X(r=0.999) $27.0{\%}$ group : Y=8.6797 + 0.1208X(r=0.997) $21.0{\%}$ group : Y=8.4081 + 0.1052X(r=0.990) $15.0{\%}$ group : Y=8.4309+ 0.0995X(r=0.990)

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Spat Collection of the Ark shell, Scapharca in the West Coast of Korea (큰이랑피조개, Scapharca satowi의 자연채묘)

  • 송홍인;박광재;조영록;박영제
    • Journal of Aquaculture
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    • v.15 no.2
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    • pp.95-101
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    • 2002
  • During the periods from lily to October, 2000 in Hongseong and lucy to October, 2001 in Taean in the west coast of Korea, the following environmental conditions prevailed : water temperature : 22.0~26.817, salinity 27.23 ~30.80%, dissolved oxygen 4.12 ~6.26 ml/l, pH 7.89 ~8.09, phosphate 0.39 ~0.65 $\mu m$ , inorganic nitrogen 5.05~9.26 $\mu m$, suspended solid 5.4~20.8 mg/l and chemical oxygen demand 1.12~1.87 mg/l. The B-shaped veliger larvae of the Ark shell occurred in maximum number at $25^{\circ}C$ prevailing from mid-August at Hongseong and Taean. Full grown larvae reached maximum abundance from late August. To identify the effectiveness of the substratum for spat collection, raschel net were tested to Larval settlement. The most effective depth to collect the larvae in natural environment was the collectors suspended at 7~8 m depth. At these depths, about 49 to 94 spats were found on the collector (40$\times$50 cm), The growth of shell height (Y) to shell length (X), and total weight (W) to shell length (L) could be formulated as follows respectively: Hongseong: SH = 0.7168 SL -0.6466 ( $r^2$ = 0.9839), TW = $0.0001SL^{3.1705}$ ($r^2$ = 0.9882) Taean: SH = 0.736 SL -0.8824 ($r^2$ : 0.9899), TW : 0.00005 $SL^{3.3731}$ ($r^2$ : 0.9899)

Correlationship between Artificial Maturation Season and Reproduction Coefficient in the Cultured Eel Anguilla japonica (양식산 뱀장어 Anguilla japonica에 있어서 인공성성숙시기와 번식률과의 상관관계)

  • Bae, Jun-Young;Kim, Dae-Jung;Lee, Jung-Uie;Son, Sang-Gyu;Lee, Jong-Kwan
    • Journal of Aquaculture
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    • v.20 no.4
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    • pp.219-225
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    • 2007
  • This study investigated the correlationship between artificial maturation season and reproduction coefficient of cultured eel Anguilla japonica from May (spring) to next January (winter). The brood stock, female eels ($400{\sim}600\;g$) were artificially matured by weekly intramuscular injections of salmon pituitary extracts (SPE, 20 mg/fish) to induce a completion of vitellogenesis. After completion of vitellogenesis, final oocyte maturation and ovulation was induced by injection of $17{\alpha}$, $20{\beta}-dihydroxyprogesterone$ (DHP) at about $2\;{\mu}g/g$ body weight. Most fish ovulated $15{\sim}18\;h$ following the DHP injection. The ovulated fish were induced to natural spawning or artificial fertilization by the dry method. Males ($200{\sim}350\;g$) were received weekly intramuscular injections of human chorionic gonadotropin (HCG) at a dosage of 1 IU/g body weight to induce testicular maturation and spermiation. Seasonal reproduction coefficient which includes the rate of ovulation, buoyancy, fertilization and hatching of eggs in the artificially matured eel during spring to summer ($May{\sim}July$) were significantly higher than the other season, while there were no significant difference among spring and summer (P<0.05). Furthermore, the number of eggs spawned and larvae hatched in the artificially maturated eel during spring to summer ($May{\sim}July$) were significantly higher than the other season, while there were no significant difference in spring and summer (P<0.05). These results indicate that artificial maturation by hormone treatment of A. japonica was successful only during spring to summer, which is the maturation period in the wild stock in nature. Consequently, it is possible to determine the period of artificially induced sexual maturity by the reproduction coefficient which includes the rate of ovulation, buoyancy, fertilization and hatching of eggs in the cultured eel A. japonica.

No Association between (AAT)n Repeat Polymorphisms in the Cannabinoid Receptor 1 Gene and Smooth Pursuit Eye Movement Abnormality in Korean Patients with Schizophrenia (한국인 조현병 환자에서CNR1 유전자의 (AAT)n 삼핵산 반복 다형성과 안구추적운동 이상에 대한 연합 연구)

  • Kim, Min Jae;Kim, Chae-Ri;Park, Jin Wan;Pak, Doo Hyun;Shin, Hyoung Doo;Choi, Ihn-Geun;Hahn, Sang Woo;Hwang, Jaeuk;Lee, Yeon Jung;Woo, Sung-Il
    • Korean Journal of Biological Psychiatry
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    • v.23 no.4
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    • pp.148-156
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    • 2016
  • Objectives According to previous studies, the cannabinoid receptor 1 (CNR1) gene could be an important candidate gene for schizophrenia. Some studies have linked the (AAT)n trinucleotide repeat polymorphism in CNR1 gene with the risk of schizophrenia. Meanwhile, smooth pursuit eye movement (SPEM) has been regarded as one of the most consistent endophenotypes of schizophrenia. In this study, we investigated the association between the (AAT)n trinucleotide repeats in CNR1 gene and SPEM abnormality in Korean patients with schizophrenia. Methods We measured SPEM function in 167 Korean patients with schizophrenia (84 male, 83 female) and they were divided according to SPEM function into two groups, good and poor SPEM function groups. We also investigated allele frequencies of (AAT)n repeat polymorphisms on CNR1 gene in each group. A logistic regression analysis was performed to find the association between SPEM abnormality and the number of (AAT)n trinucleotide repeats. Results The natural logarithm value of signal/noise ratio (Ln S/N ratio) of the good SPEM function group was $4.34{\pm}0.29$ and that of the poor SPEM function group was $3.21{\pm}0.70$. In total, 7 types of trinucleotide repeats were identified, each containing 7, 10, 11, 12, 13, 14, and 15 repeats, respectively. In the patients with $(AAT)7$ allele, the distributions of the good and poor SPEM function groups were 18 (11.1%) and 19 (11.0%) respectively. In the patients with $(AAT)_{10}$ allele, $(AAT)_{11}$ allele, $(AAT)_{12}$ allele, $(AAT)_{13}$ allele, $(AAT)_{14}$ allele and $(AAT)_{15}$ allele, the distributions of good and poor SPEM function groups were 13 (8.0%) and 12 (7.0%), 4 (2.5%) and 6 (3.5%), 31 (19.8%) and 35 (20.3%), 51 (31.5%) and 51 (29.7%), 36 (22.2%) and 45 (26.2%), 9 (5.6%) and 4 (2.3%) respectively. As the number of (AAT) n repeat increased, there was no aggravation of abnormality of SPEM function. Conclusions There was no significant aggravation of SPEM abnormality along with the increase of number of (AAT)n trinucleotide repeats in the CNR1 gene in Korean patients with schizophrenia.

SPAT COLLECTION AND THE GROWTH OF ANADARA BROUGHTONI SCHRENCK (피조개의 채묘와 초기성장)

  • YOO Myung-Suk;YOO Sung Kyoo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.7 no.2
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    • pp.79-86
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    • 1974
  • The results from the experiment of natural collection and growth of arkshell(Anadara broughtoni, SCHRENCK) spat, which was collected at Seok-gok Bay located at Chang-weon-gun, Korea, and grown in the 1ittoral zone of Sa-gok-ri, Geo-je-gun, Korea, beginning from August 1,1973 to April 8,1974 are as follows; The larvae of arkshell came out from the very first day of the study August 1, which continued till the end of September, whose amount was not so much varied, but relatively continuous. The drifting larvae were also rather small amount, from which some 200 to 400 larvae were attached through the respective collecting equipment made from straw with the dimension of length 1.5m and breadth 12cm. It is regarded relatively large amount collected and recognised worth while enough to use as the industrial collecting method. The average shell length of spat attached was 0.54mm on 17th September, 4.11mm on 21st October, 10.47mm on 25th November in 1973 and 11.08mm on 8th April in 1974 whose progress was recognized relatively faster, comparing with the other up-to date report, The relationship between the shell length(L) and the longest radial rib(R) was as follows: Below 2.5mm of the shell length: R=0.7393 L -0.0080 Above 2.5mm of the shell length: R=0.8253 L-0.2595 And the relationship between the shell length (L) and the shell breadth (B) was as follows: Below 2.5mm of the shell length: B=0.3505 L +0.0527 Above 2.5mm of the shell length: B=0.4631 L -0.3602 The exponential curve equation between shell length (L) and the total weight (W)was as follows : Below 16mm of the shell length: W=0.19957 $L^{2.5726}$ Above 16mm of the shell length: W=0.20602 $L^{2.8400}$ In view of the above the relative growth among the shell length, the longest radial rib and the shell breadth was changed in the vicinity of 2.5mm of the shell length. And relationship between the shell length and the total weight was changed in the vicinity of 16mm of the shell length.

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The E-mail Survey on the Neck Pain for Acupuncture and Moxibustion Clinical Guideline (경항통에 관한 침구임상 진료지침 개발을 위한 전자우편 설문조사)

  • Kim, Hyun-Wook;Kim, Sung-Soo;Nam, Dong-Woo;Kim, Eun-Jung;Hong, Kwon-Eui;Kim, Sung-Chul;Kim, Sun-Woong;Lee, Jae-Dong;Kim, Kap-Sung;Lee, Geon-Mok
    • Journal of Acupuncture Research
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    • v.26 no.3
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    • pp.67-80
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    • 2009
  • Objectives : The purpose of this survey is the development on the neck pain for acupuncture and moxibustion clinical guideline. Methods : The survey questionnaire was developed by the committee of experts who major in acupuncture & moxibustion or statistics for acupuncture clinical trial protocol development. The questionnaires were distributed via e-mail to 75 members of Korean Acupuncture & moxibustion society. 57 members completed answers, and the computerized data were analyzed by SPSS 17.0 statistical program. Results and Conclusions : 1. The first selected pattern identification on the neck pain This study shows that the meridian pattern identification was selected 35 times(61.4%), the pattern identification based on cause of disease was selected 8 times(14.0%), the visceral pattern identification was selected 7 times(12.3%), the other pattern identification was selected 4 times(7.0%), Qi blood yin yang pattern identification was selected 2 times(3.5%), according to symptoms was selected 1 time(2.4%). 2. Meridian pattern identification Small intestine meridian of hand Taeyang was used 39 times(18.1%), Large intestine meridian of hand Yangmyeong and Bladder meridian of foot Taeyang was used 34 times(15.7%), Gall-bladder meridian of foot Soyang was 32 times(14.8%), Tripple energizer meridian of hand Soyang was used 31 times(14.4%), Governor meridian was used 30 times(13.9%), Lung meridian of hand Taeeum was used 8 times(3.7%), Heart meridian of hand Soeum and Pericarduim meridian of hand Gworeum was used 4 times(1.9%). 3. Pattern identification based on cause of disease Wind-Cold-Dampness was used 31 times(17.5%), Accumulation of the collateral by Phelgm-Dampness was used 16 times(14.0%), affection by exopathogen Wind-Cold(stiff neck, sprain of cervical) was used 13 times (11.4%), Defecient-Cold was used 10 times(8.8%), affection by exopathogen Wind-Dampness was used 9 times(7.9%), Deep Invasion by Wind-Cold was used 8 times(7.0%), Wind-Cold was used 7 times (6.1%), Wind-Cold was used 6 times(5.3%), Accumulation in the Center by Phelgm-Dampness, Imparement of bou fluid by Pathogenic Heat, Wind-Heat with Dampness was used 5 times(4.4%), affection by exopathogen Wind-Dampness and Accumulation of the collateral by Wind-Cold was used 4 times(3.5%), Invasion of Dampness-Heat was used 2 times(1.8%). 4. Visceral pattern identification Rising of the Liver yang was used 16 times(41%), Yin deficiency of Liver and Kidney+pathogens was used 15 times(38.5%), Yin deficiency of Liver and Kidney was used 8 times(20.5%) on this survey.

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Response of the Growth and Root Development of Shade Landscape Plants by Slit Ventilation Treatment into Indoor Container (실내용기 내 슬릿(Slit)처리가 내음성 조경식물의 생육과 뿌리발달에 미치는 영향)

  • Ju, Jin-Hee;Han, Jung-Hwa
    • Journal of the Korean Institute of Landscape Architecture
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    • v.37 no.3
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    • pp.105-112
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    • 2009
  • This study has attempted to facilitate various new technologies related to indoor containers and develop a desirable planting environment after investigating the growth (including root growth) of shade-tolerant landscape plants under slit processing, a natural indoor ventilation system. The following results were found: In terms of the shoot growth of Fatsia japonica in a slit container, no distinctive difference was observed in comparison with the control group. However, growth was good when the container 250mm tall or taller. Therefore, it was verified that optical soil depth is more important than slit processing in shoot growth of Fatsia japonica. In Fatsia japonica root length was observed as follows: Control 2(250mm) > Slit 2(250mm) > Control 1(195mm) > Slit 3(360mm) > Control 3(360mm) > Slit 1(195mm). The largest growth was observed in Control 2(250mm), which had no slit processing. In term of root width, this was lower than the initial value in all groups, which means that the root grew vertically, not horizontally. In terms of plant height of Ophiopogon japonicus, a gradual increase was observed in the control group that had no slit processing. No significant growth was detected in the slit system, however. In terms of shoot number, slit containers were generally higher than the control group. In terms of fresh and dry weights, on the contrary, slit containers were mostly lower than the control group. In Ophiopogon japonicus, root length was observed as follows: Slit 2(250mm) > Slit 1(195mm) > Control 2(250mm) > Control 3(360mm) > Slit 3(360mm) > Control 1(195mm). In Ardisia japonica, slit containers were mostly greater than control group in terms of plant height. The greatest plant height was observed at Slit 2(250mm) instead of Slit 1(195mm) and Slit 3(360mm). Except for plant height and shoot number, however, no significant shoot and root growth was observed. Root length was observed as follows: Slit 2(250mm) > Slit 3(360mm) > Control 3(360mm) > Slit 1(195mm) > Control 2(250mm) > Control 1(195mm). Therefore, root length in slit containers was mostly greater than in the control group. The width of root, however, declined in general.

Sorption Studies of $Cd^{2+}$ on Calcite: Kinetics and Reversibility (방해석의 $Cd^{2+}$ 흡착현상에 대한 연구)

  • Yoon, Hyeon;Reeder, Richard J.
    • Journal of the Mineralogical Society of Korea
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    • v.15 no.2
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    • pp.104-113
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    • 2002
  • The sorption of Cd$^{2+}$ on calcite was studied in aqueous solutions of several electrolytes. The Cd$^{2+}$ concentration, 10$^{-8}$ M, was kept well below saturation with respect to CdCO$_3$(s). Sorption behavior of Cd$^{2+}$ in different ionic strengths of NaClO$_4$solutions shows that sorption is independent of ionic strength. This result suggests that Cd$^{2+}$ sorption on calcite surface is of a specific nature, and adsorption is controlled by an inner-sphere type of surface complex. Two stages in the sorption behavior could be identified: an initial rapid uptake, followed by slower uptake reaching a maximum steady state by 145 hrs. No evidence was observed for surface precipitation, although it can not be entirely ruled out. Desorption of Cd$^{2+}$ from the calcite surface after resuspension into Cd-free solution is initially very rapid, but depends partly on the previous sorption history. Desorption behavior of Cd$^{2+}$ show that an initial rapid desorption followed either by slow uptake reaching a maximum, as in the adsorption experiments, or slowing desorption to reach a steady state minimum. This irreversible behavior of Cd$^{2+}$ sorption and desorption may act as one of the controls for regulating the mobility of dissolved Cd$^{2+}$ natural aqueous systems. Calculated adsorption partition coefficients suggest that overall sorption and desorption process in the concentration range are controlled by d single mechanism.ingle mechanism.

consumers' purchasing behavior of functional cosmetics and Inula based functional cosmetics merchandising research (국내 소비자의 기능성화장품 구매행태 및 선복화 활용 기능성화장품 상품화를 위한 연구)

  • Han, Do-Kyung;Lee, Hyun-Jun;Lee, Eun-Hee;Paik, Hyun-Dong;Shin, Dong-Kyoo;Park, Dae-Sub;Hwang, Hye-Seon;Hong, Wan-Soo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.8
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    • pp.236-250
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    • 2016
  • This study was conducted to provide baseline data regarding functional cosmetics so that Inula. based cosmetics can increase its competitiveness in the market as well as to understand current trends to enable anticipation of demands for future product development. For this research, general consumers over the age of 20 residing in Seoul and the Gyeonggi district were surveyed. The results show consumers preferred serum-type products among various types of cosmetics, and that they purchased these once every 1-3 months. Consumers also preferred these products in less than 10-30ml capacity, and at costs of less than 30,000-50,000 KRW. For whitening, functional cosmetics consumers also preferred the serum type, in less than 30-50ml capacity and priced less than 30,000-50,000 KRW. Consumers preferred to purchase functional cosmetics in single units. The major purchasing location, with a high preference rate, was cosmetic stores, and the major sources of information, also with high preference rates, were 'experienced reviews from family, friends and acquaintances' and 'TV advertisements'. Respondents selected 'over 50,000 KRW' the most for all items when responding to 'Purchase Intent for Functional Cosmetics containing Inula', and responded that they were willing to pay 10%-30% more for functional cosmetics containing Inula compared to standard functional cosmetics. These results show that businesses in the cosmetics industry need to take consumer demand into account when developing new functional cosmetic products, as well as establish plans to create specialized spaces that provide better quality service and increase word of mouth effect through better utilization of various types of offline media, social media, and blogs. The study also shows a need for businesses to develop products fully utilizing the Inula flower, which has been shown to be effective as a natural skin whitener, wrinkle reducer and skin moisturizer, to appeal to the increasing number of customers interested in health and beauty.

Investigation on the Cause of Bad Natural Seed Collection of the Pacific Oyster, Crassostrea gigas: Relationships between the Conditions of Mother Shell and the Viability of the Released Eggs and Larvae Based on the Pathological and Embryological Survey (참굴 채묘 부진 원인 구명에 관한 연구 -병리 발생학적 조사를 통한 참굴 모패의 건강도와 난 및 유생의 생존율과의 상관관계 구명 -)

  • PARK Mi Seon;LYU Ho Young;LEE Tae Seek
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.32 no.1
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    • pp.62-67
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    • 1999
  • Infection rates of oyster ovarian parasite, Marteiliodes chungmuensis and productivity of the oyster shellstock infected with the parasite were investigated at the main seed collection areas in the southern coast of Korea where the extreme bad seed collection of oyster occurred in 1992 and 1993 to evaluate the cause of the bad seed collection. Additionally, the bacterial flora of the sea water and oyster lana were examined to identify the shellfish larva pathogenic bacteria like Vibrio sp. and Pseueomonas sp. In August 1992 to September 1993, infection rate of oyster ovarian parasite, M. chungmuensis at Tongyong, Kyongsangnam province, and Yosu, Chollanam province where the bad seed collection occurred, were $11.8\~100\%$ and $14.3\~100\%$, respectively. But the parasite was not detected in the shellstock collected at Daechon, Chungchongnam province. While a virus-like particle was identified in the cytoplasm of the egg infected by the parasite. The parasite infected egg was not able to fertilize completely. Uninfected egg in the gonad contaminated by the parasite could be able to fertilize but showed an abnormal development till D-shaped larva and then, died of necrosis after D-shaped lana. And some lana developed from low lipid content egg could not develop to the spat and died after the early umbo stage. The predominant bacteria in the oyster lana collected at bad seed collection areas were Pseudomonas sp. and Pseudomonas like bacteria and the occupancy rates were $53.3\~87.1\%$.

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