어린 북방전복 (Haliotis discus hannai) 에 대한 포식자 (불가사리류 제외) 의 존재 여부를 확인하고자 경북 울진 연안 3개 해역 (양정, 죽진 및 봉평)에서 SCUBA diving을 이용하여 2014년 2월부터 12월까지 총 9회에 걸친 직접 관찰 조사를 수행하였다. 조사 결과 수심 10 m 이내 (최대 15 m)의 해역에서 상대적 암반 구성 비율이 가장 높은 죽진 해역 (60.3%)에서 어린 북방전복을 포식하고 있는 총 6개체의 갈색띠매물고둥 (Neptunea cumingii)이 발견되었다. 따라서, 본 연구결과는 갈색띠매물고둥이 어린 북방전복에 대한 포식자라는 새로운 사실을 제시하고 있다.
The presence of predators (excluding starfishes) of disk abalone, Haliotis discus hannai was directly investigated by nine SCUBA divings during February-December 2014 at the coastal areas of Yangjeong, Jukjin and Bongpyeong, Uljin, Korea, where the young disk abalone seedlings were artificially released. The results revealed that a total of six individuals of Neptunea cumingii that were feeding on the young disk abalone were observed within the water depth 10m at the coastal area of Jukjin, of which bottom substrate consists of the relatively high composition rate of rocks (60.3%). Though N. cumingii is well known as a carnivorous predator of diverse marine invertebrates such as live mussels (Mytilus spp.) it is the first report that this predator also feeds on the disk abalones. Thus, our results strongly suggest that the future artificial release projects around Korean coasts necessitate extermination works of predators including newly observed N. cumingii in this study as well as previously known starfishes prior to the releases of young Pacific abalone seedlings.
의암호에 서식하고 있는 말조개의 성장과 산란생태를 파악하기 위하여, 2014년 3월부터 2015년 2월까지 상대성장식, 생식소 발달단계에 따른 생식주기와 군성숙도의 월별변화를 조사하였다. 각장에 대한 각고, 각폭, 전중, 육중간의 상대성장식에서 상관계수 (<TEX>$R^2$</TEX>) 는 0.814-0.944로 높은 상관관계를 나타내었다. 말조개의 생식소는 소화맹낭의 주변부와 족부로 연결되는 망상결체조직에 분포하며 자웅이체로, 성숙한 난과 정자는 수관을 통해 아가미 반새에서 수정되어 수정란을 아가미의 보육낭에서 부화시켜 체외로 방출하는 난태생종이었다. 서식 지역의 월별 평균수온은 <TEX>$3.9-25.9^{\circ}C$</TEX> 범위였다. 월별 비만도는 0.16-0.22 범위로 하계인 8월-9월에 낮은 값을 보이다가 10월부터 증가하여 11월과 1월에 0.22로 정점을 보였다. 월별 육중량비는 21.3-31.4%로 비만도의 월별 변화와 같은 경향을 나타내었다. 생식소지수는 0.00-4.00 범위를 나타내었고, 4월-7월까지 정점을 보인 후 8월부터 급격히 감소하였다. 생식년주기는 분열증식기 (11-1월), 성장기 (2-3월), 성숙기 (2-5월), 산란기 (4-9월), 회복기 (8-12월)로 구분되어 하계산란종이었다. 의암호산 말조개의 산란기는 4-9월 (주산란기 4-7월) 이였으며, 군성숙 각장은 29.4 mm였다.
The reproductive ecology of freshwater bivalve, Unio douglasiae in Lake Uiam were examined from March 2014 to February 2015. The gonads distributed in reticular connective tissue, the dioecious clams take an internal fertilization and fertilized eggs are stored in the foster-sack in the gills, then the hatched juveniles are released outside after an ovoviviparous process. The gonad index (GI) began to increase in April, reached the maximum value in July and to decrease in August. The reproductive cycle of U. douglasiae can be divided into five successive stages: multiplicative stage (November to January), growing stage (February to March), mature stage (February to May), spawning stage (April to September), recovery stage (August to December). The spawning periods were from April to September, and the main spawning occurred between April and July. The shell length at 50% group maturity was estimated to be 29.4 mm.
굴 미수정란의 동결보존에 적합한 동해방지제의 종류, 농도 및 침투 시간을 구명하기 위하여 4가지 동해방지제 (DMSO, EG, methanol, PEG) 를 대상으로 수정률, 부화율 및 형태 이상률을 조사하였다. 동해방지제의 농도 및 침지시간은 각각 5, 10, 15, 20%와 10, 20, 30, 40분이었다. 침지 후 미수정란은 정상 정자와 수정되었고, 수정률, 부화율 및 형태 이상률은 동해방지제의 종류와 농도 및 침지시간에 영향을 받았다. 동해방지제의 농도와 침지시간의 증가에 따라 수정률과 부화율은 낮아졌고, 대부분의 동해방지제에서 5-10% 농도와 10-20분의 짧은 침지시간에서 좋은 결과를 보였다. 수정률과 부화율을 근거로 굴 미수정란에 가장 적합한 동해방지제는 DMSO였으며, 처리 농도와 침지 시간은 각각 5%와 10-20분이었다.
The Pacific oyster Crassostrea gigas oocytes were exposed to 4 cryoprotectants, dimethyl sulfoxide (DMSO), ethylene glycol (EG), methanol, or polyethylene glycol (PEG), each with 4 four concentrations (5, 10, 15, and 20%) and for 10, 20, 30 or 40 minutes for permeation. The oocytes were then fertilized, using normal sperm of the species. Fertilization and hatching rates were clearly influenced by cryoprotectant species and their concentration and permeation time. Overall, they decreased as concentrations and permeation time of cryoprotectants increased with optimum results at concentrations of 5-10% and a permeation time of 10 minutes. Larval abnormalities, a sign of the chemical damage, were a representative phenotype which was higher at a higher concentration and longer duration of the chemicals. In conclusion, best result was from 5% DMSO exposure for 10-20 minute permeation.
본 연구에서는 수온 증가에 따른 말전복 (Haliotis gigantea) 과 둥근전복 (H. discus discus) 헤모림프의 생리 및 면역학적 변화를 관찰하기 위하여 위 두 전복을 20, 22, 24, 26 및 <TEX>$28^{\circ}C$</TEX> 수온에 각각 4 일간 노출시켰다. 노출 결과, 헤모림프의 totalo-protein (TP), glucose, calcium (Ca) 은 둥근전복 (H. discus discus)이 말전복 (H. gigantea) 보다 높은 값을 보였으나, magnesium (Mg), alkaline phosphatase (ALP) 두 전복에서 유사한 값을 보였다. 그리고 면역인자인 PO에서는 둥근전복 (H. discus discus)이 더 높게 나타났다. 수온 증가에 따른 헤모림프의 TP, glucose, Mg, AST, ALT 및 ALP는 유의적인 변화가 나타나지 않았다. 하지만 헤모림프의 Ca 농도는 둥근전복 (H. discus discus)에서 <TEX>$24^{\circ}C$</TEX> 이상, 말전복 (H. gigantea)에서는 <TEX>$26^{\circ}C$</TEX> 이상의 수온에서 유의적 증가를 보였다. 그리고 면역인자인 phenoloxidase (PO) 는 둥근전복 (H. discus discus)은 <TEX>$22^{\circ}C$</TEX> 이상 말전복 (H. gigantea) 에서는 <TEX>$26^{\circ}C$</TEX> 이상의 수온에서 유의적 감소를 나타내었다. 결론적으로 말전복 (H. gigantea)은 <TEX>$24^{\circ}C$</TEX> 이상에서 혈액학적 변화를 보였고, <TEX>$26^{\circ}C$</TEX> 이상에서 면역학적 변화를 보였다. 둥근전복 (H. discus discus)은 <TEX>$26^{\circ}C$</TEX> 이상에서 혈액학적 변화를 보였고, <TEX>$22^{\circ}C$</TEX> 이상에서 면역학적 변화를 나타내었다.
This study was conducted to examine the effects of alterations in water temperature (WT) on biochemical and immunological factors in the hemolymph of the abalones, Nordotis gigantea and Haliotis discus discus. The abalone were exposed to various WT; 18, 20, 22, 24, 26 and 28℃ for 96 hours. In biochemical factors, total-protein (TP), glucose, magnesium (Mg), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were not significant changes in hemolymph of N. gigantea and H. discus. But calcium was significantly increased by high WT (≥ 24℃). In immunological factor, The phenoloxidase (PO) activity was decreased in hemolymph of N. gigantea and H.D. hannai exposed to high temperature (≥ 22℃) compared to the control (P < 0.05). Whereas alkaline phosphatase (ALP) was not significantly changed. These results suggested that high temperature adversely affects the immunity of N. gigantea and H.D. hannai.
본 연구는 염화아연 만성노출에 따른 북방전복의 미량금속 축적 농도, 생존율, 탈락률 및 조직학적 지표 변화에 대하여 알아보고자 하였다. 실험은 1개의 대조구와 4개의 노출구 (0.3, 0.8, 1.3, <TEX>$1.8\;ZnCl_2\;mg/L$</TEX>) 였다. 염화아연에 노출된 북방전복의 체내 미량금속 축적 농도는 모든 노출구에서 농도의존적으로 증가하는 결과를 보였다. 생존률 및 탈락률은 대조구에 비해 노출구에서 농도의존적으로 나타났다. 북방전복의 발, 아가미, 간췌장의 조직학적 변화는 시간이 경과함에 따라 대조구에 비해 노출구에서 뚜렷하게 나타났다.
This study was conducted to find out concentration of trace metal, survival rate, falling rate and structural changes of abalone, Haliotis discus hannai exposed to zinc chloride. Experimental groups were composed of one control condition and four exposure conditions (0.3, 0.8, 1.3, 1.8 ZnCl2 mg/L). The accumulation of trace metal (zinc) in abalone was significantly increased all exposure group. Though the exposure groups had lower survival rate than the control group, higher falling rate than the control group. Histopathological changes in the foot, gill and hepatopancreas of abalone revealed obvious with exposure group than control group.
본 연구는 먹이생물의 종류와 서식 위치 (패각 크기)에 따라서 지중해담치의 여과율이 수온에 따라 어떻게 변동하는 지를 알아보고자 하였다. 실험에 사용된 먹이생물은 Isochrysis galbana, Chaetoceros didymus and Prorocentrum dentatum의 3 종류이다. 지중해담치의 크기 (각고)는 중부조간대 상부 지역 (+ 5 cm MSL)에 서식하는 개체가 중부조간대 하부지역 (- 58 cm MSL)에 서식하는 개체보다 월등히 작았다. 지중해담치의 여수율과 섭식율은 먹이생물의 종류에 상관없이 중부조간대 상부에 서식하는 지중해담치가 중부조간대 하부에 서식하는 지중해담치보다 높은 값을 보였다. 전반적으로 수온에 따른 여수율과 섭식율 변동은 동일한 변동 양상을 보였다. 즉 수온이 상승함에 따라서 여수율과 섭식율도 증가하다가, 수온 <TEX>$20-25^{\circ}C$</TEX> 정도에서 최대값을 보이며, 이 후 점차 감소하는 경향을 보였다. 다항회귀분석식에서 추정한 최대 여수율과 섭식율을 보이는 이론적 적정 수온 역시 <TEX>$20-25^{\circ}C$</TEX>의 범위내로 나타났다. 먹이생물의 종류에 따라서는 여수율과 섭식율이 약간 다른 변동을 보였다. 대체적으로 여수율과 세포수 기준 섭식율은 지중해담치의 서식위치 (조고)나 먹이생물의 종류에 상관없이 거의 유사한 경향을 보였다. 반면에 탄소함량 기준 섭식율의 경우 먹이생물이 P. dentatum일 경우가 I. galbana나 C. didymus일 경우 보다 월등히 높은 값을 보였다.
This study was performed to describe the influence of temperature on the clearance rate and ingestion rate of the blue mussel, Mytilus galloprovincialis with three food organisms and habitat location (shell size) of mussel. Food organisms used in this experiments were Isochrysis galbana, Chaetoceros didymus and Prorocentrum dentatum. The size of mussels inhabiting higher midlittoral zone was smaller than those of lower midlittoral zone. Regardless of the kind of food organisms, filtration rates and ingestion rates of higher midlittoral mussels were higher than those of lower midlittoral mussels in experiment temperature conditions. The variation of filtration rate and ingestion rate showed same tendency with temperature. Filtration rates and ingestion rates increased with temperature, and recorded maximum values at 20-25℃ of temperature, and thereafter decreased gradually. Theoretical optimum temperatures showing maximum filtration rates and ingestion rates estimated from polynomial regression curves were also in the range of 20-25℃. Blue mussels showed different variation of filtration rate and ingestion rate with the kind of food organisms. Filtration rates and ingestion rate based on cell number were similar regardless of habitat location(tidal elevation) and food organisms. Ingestion rates based on carbon content showed very high values in case of P. dentatum beside I. galbana and C. didymus as food organism.
2007년 12월 7일 Hebei spirie호 유류유출 후 2008년 4월에 발생한 서해안의 바지락 평균 폐사율은 22.4%로 사고 이전인 2007년 4월의 9.2%에 비하여 급격히 증가한 것으로 나타났다. 특히 유류가 유입된 태안 및 보령, 서산 지역에서는 30% 내외로 폐사율이 매우 높게 나타난 반면, 비오염지역인 인천, 경기도를 비롯하여 지형적인 조건과 방제작업 등으로 유류유입이 적었던 근소만과 천수만 내측 등에서는 10% 내외로 낮게 나타났다. 2009년 폐사율은 6.0%로 2008년의 22.4%에 비해 급격히 감소하였다. 2009년은 2008년과 비교하여 폭풍 등 해황이 불안정하여 저질변동이 많았으나, Hebei sprit호 유류유출로 인한 피해지역인 태안과 보령, 서산 지역에서는 폐사율이 낮아진 반면, 비 피해지역인 인천과 경기에서는 비슷하거나 높게 나타났다. 2010년 폐사율은 8.6%로 2009년의 6.0%에 비해 약간 증가하였는데, 오염지역과 비오염지역을 구분하지 않고 모두 증가하였다. 따라서 유류가 유입된 태안 및 보령, 서산지역의 2008년 4월에 발생한 바지락 폐사는 Hebei spirit호 유류유출과 관련이 있는 것으로 판단된다. 우리나라 바지락의 전체 생산량은 유류사고 전인 2007년에는 27,459 톤이 사고 직후에 폐사가 발생하였음에도 불구하고 2008년에 36,302 톤, 2009년에 40,392 톤, 2010년에는 36,248 톤으로 증가한 것으로 나타났다. 생산량을 지역별로 살펴보면 유류피해 지역인 충남의 바지락 생산량은 유류사고 전인 2007년에는 10,598 톤이던 것이 사고 직후인 2008년에 5,048 톤으로 급격히 감소하였으며, 2009년에는 7,065 톤, 2010년에는 유류피해 전보다 많은 12,921 톤으로 증가한 것으로 나타났다. 비피해지역인 전남의 바지락 생산량은 유류사고 전인 2007년에는 1,252 톤이던 것이 사고 직후인 2008년에는 12,248 톤으로 급격히 증가하였으며, 2009년 9,566 톤, 2010년 2,770 톤으로 감소한 것으로 나타났다. 따라서 전체 바지락 생산량에서 2008년에 우리나라 생산량이 감소하지 않고 증가한 이유는 유류피해가 없던 전남지역에서 물속에 서식하던 바지락이 대량으로 생산되었기 때문이다.
After oil outlow accident of Hebei spirit in December 7, 2007, the motality of manila clam, Ruditapes philippinarum in the west coast of South Korea, was significantly increased from 9.2% in April, 2007 to 22.4% in April 2008. Although the mortality was about 10% in the tidal flat of Geunso Bay and Cheonsu Bay, Incheon and Gyeonggi-do, the values was significantly high about 30% in water coast of Taean, Boryeong and Seosan in where the spilled oil was getting into fishery zone. However, the mortality in water coast of Taean, Boryeong and Seosan was decreased from 22.4% in 2008 to 6.0% in 2009. Also, we found that the mortality in contaminated and non-contaminated water zones was both slightly increased from 6.0 in 2009 to 8.6% in 2010, Therefore, these results are indicating that the significant high mortality observed in water coast of Taean, Boryeong and Seosan at April, 2008 was due to the crude oil accident outflow from tanks of Hebei spirit. Although the mortality of manila clam was significantly decreased in middle west coast of South Korea after the accident of Hebei spirit in December, 2007, the annual production of manila clam in South Korea was sustainedly from 27,459 ton in 2007, 36,302 ton in 2008, 40,392 ton in 2009, to 36,248 ton in 2010. In the production of manila clam by regional groups, the amount in sea coast of Chungnam, where was damaged by crude oil, was significantly decreased from 10,598 ton in 2007 to 5,048 ton in 2008, but then was significantly increased to 7,065 ton in 2009, and to 12,921 ton in 2010. However, in sea coast of Jeonnam that was not damaged by crude oil, the amount was significantly increased from 1,252 ton in 2007 to 12,248 ton in 2008, but then was significantly decreased to 9,566 ton in 2009, and to 2,770 ton in 2010. Therefore the results are suggesting that a increasing of the total annual production of manila clam in South Korea in 2008 when was 1 year after the oil accident of Hebei spirit was due to increasing of clam production in a coast of Jeonnam in where was not damaged by crude oil.
Observations in beach, intertidal and upper subtidal environments in Peter the Great Bay (north-western East Sea) have shown that attached algae were found on empty shells of 13 species of epifaunal and infaunal bivalve mollusks. Thirteen algae species were identified on empty dislodged shells but more than 50 species are known to be epibiotic on living bivalves. The dislodgement of shells with attached algae takes place in semi-enclosed, low-energy areas, as well as those which are open and affected by strong wave action, indicating the large scale of this phenomenon. The significance of seaweed transportation of living mollusks and their empty shells in the coastal zone, involving both taphonomic and ecological processes, is stressed. Algae appear to be a taphonomic agent and play a similar role as compared to birds or hermit crabs, but they act passively and contribute to environmental mixing in death assemblages in coastal environments.
Toll-like receptors (TLRs) are a major pattern recognition receptor that recognize the structure of invading pathogen and play key roles by triggering immune response. In this study, we identified a sequence of TLR homolog and characterized at molecular level from the abalone (Haliotis discus hannai). Multiple alignments and phylogenetic analysis of abalone TLR protein belongs to the TLR 2/6. Expression level of abalone TLR2/6 in the tissue was comparatively high in the mantle, gill, digestive duct, and hemocytes, but lowest in the muscle. Expression level of abalone TLR2/6 mRNA in the mantle, gill, digestive duct, and hemocytes was 20-fold, 60-fold, 115-fold, 112-fold higher than in the muscle, respectively. Expression level of abalone TLR2/6 mRNA in the mantle was steadily increased until 12 h and decreased post-infection with Vibrio parahemolyticus. While the expression level of abalone TLR2/6 mRNA in the gill and hemocytes was drastically increased at 6 and 9 h post-infection with Vibrio parahemolyticus, respectively. These results suggest that abalone TLR2/6 is conserved through evolution and may play roles similar to its mammalian counterparts.
A stand-alone BLAST server is available that provides a convenient and amenable platform for the analysis of molluscan sequence information especially the EST sequences generated by traditional sequencing methods. However, it is found that the server has limitations in the annotation of molluscan sequences generated using next-generation sequencing (NGS) platforms due to inconsistencies in molluscan sequence available at NCBI. We constructed a web-based interface for a new stand-alone BLAST, called PANM-DB (Protostome DB) for the analysis of molluscan NGS data. The PANM-DB includes the amino acid sequences from the protostome groups- Arthropoda, Nematoda, and Mollusca downloaded from GenBank with the NCBI taxonomy Browser. The sequences were translated into multi-FASTA format and stored in the database by using the formatdb program at NCBI. PANM-DB contains 6% of NCBInr database sequences (as of 24-06-2015), and for an input of 10,000 RNA-seq sequences the processing speed was 15 times faster by using PANM-DB when compared with NCBInr DB. It was also noted that PANM-DB show two times more significant hits with diverse annotation profiles as compared with Mollusks DB. Hence, the construction of PANM-DB is a significant step in the annotation of molluscan sequence information obtained from NGS platforms. The PANM-DB is freely downloadable from the web-based interface (Malacological Society of Korea, http://malacol.or/kr/blast) as compressed file system and can run on any compatible operating system.
An aeolid nudibranch species Flabellina athadona (Bergh, 1875) is newly recorded from Korean waters. This species is distinguished from other congeneric species by the following characteristics: translucent white body, deep orange colored digestive glands, plenty of white specks, and a reversed Y-shaped marking on the head between rhinophores and oral tentacles. In this report, we also provide an identification key for the genus Flabellina in Korea, photographs, and diagnostic characteristics of F. athadona. Molecular identification using mtDNA cox1 partial sequences is also provided to help differentiate F. athadona from some of its closely related congeneric species.
The family Olividae includes predatory species with medium-sized, glossy, elongated oval-shaped shell. As sand-dwellers, they are broadly distributed in tropical and subtropical oceans. They feed mostly on other mollusks and carrions including sea snails and bivalves. To date, two species in the genus Amalda (subfamily Ancillinae) have been reported in Korean waters. In this study, Amalda rubiginosa (Swainson, 1823) was collected from Korean waters and morphologically described in details as a first record.
