ISSN : 1225-3480
피조개 유생의 최적 성장과 먹이생물의 이용성을 높이기 위해 현재 인공종자생산에서 많이 이용되고 대량배양이 용이한 미세조류 4종 (I. galbana, P. lutheri, C. simplex, T. tetrathele) 을 대상으로 먹이생물이 피조개 유생의 발달단계별 성장 및 생존에 미치는 영향을 조사하였다. 초기 D형 유생을 대상으로 먹이생물 4종을 단독 또는 혼합 공급하여 8일간의 사육 실험 결과, 먹이생물 4종을 혼합 공급한 실험구에서 평균 각장 <TEX>$129.6{\pm}5.7{\mu}m$</TEX>로 가장 빠른 성장을 보였고 (P < 0.05), P. lutheri와 C. simplex의 혼합 공급구 (<TEX>$125.3{\pm}5.6{\mu}m$</TEX>) 와는 유의한 차이가 없었으며, I. galbana와 C. simplex 등 다른 2종을 혼합한 공급구 보다는 유의하게 높은 성장을 나타내었다 (P < 0.05). 그리고 초기 각정기, 각정기, 후기 각정기 유생 단계에서의 성장도 초기 D형 유생 단계와 유사한 경향을 보였으며, 일간성장과 생존율은 성장 실험과 유사한 경향을 나타내었다. 초기 D형 유생을 대상으로 먹이생물 4종을 <TEX>$0.5{\times}10^4$</TEX>, <TEX>$1{\times}10^4$</TEX>, <TEX>$2{\times}10^4$</TEX>, <TEX>$5{\times}10^4$</TEX>, <TEX>$8{\times}10^4cells/mL/day$</TEX> 밀도로 8일간 혼합 공급하여 사육한 결과, <TEX>$2{\times}10^4cells/mL$</TEX> 밀도에서 <TEX>$125.8{\pm}5.1{\mu}m$</TEX>로 가장 빠른 성장을 보였고 (P < 0.05), <TEX>$1{\times}10^4$</TEX> 과 <TEX>$5{\times}10^4cells/mL$</TEX> 공급구 간에는 유의한 차이가 없었다. 먹이 공급량이 많을수록 유생의 성장은 양호하였으나, <TEX>$8{\times}10^4cells/mL$</TEX> 밀도에서는 사육 8일째 전량 폐사하였다. 그리고 초기 각정기, 각정기, 후기 각정기 유생 단계에서도 초기 D형 유생 단계와 유사한 경향을 보였으며 일간성장과 생존율은 성장 실험과 유사한 경향을 나타내었다. 따라서 피조개 유생 사육을 위한 먹이생물은 C. simplex를 포함한 2종 이상을 혼합하여 <TEX>$1{\times}10^4-2{\times}10^4cells/mL$</TEX>의 밀도로 공급하는 것이 효과적인 것으로 판단된다.
Supply of proper microalgae is very critical because it determines total production and cost of larval Ark shell, Scapharca broughtonii during larval development stages. Besides, nutrient requirements of microalgae should be carefully determined for successful larval Ark shell production. In order to improve utilization of microalgae being used for artificial Ark shell seed production and optimum larval growth of Ark shell, growth and survival (%) of larvae on development stage of Scapharca broughtonii fed on four different microalgal species (Isochrysis galbana, Pavlova lutheri and Chaetoceros simplex, Tetraselmis tetrathele) were investigated. In D shape stage the larvae fed on mixed diet with four microalgal species showed the highest growth in shell length (129.6 ± 5.7 μm) and survival (84.2 ± 5.8%) (P < 0.05). The growth and survival (%) of the larvae fed on mixed diet with two microalgal species of P. lutheri + C. simplex were lower than mixed diet with four microalgal species and significantly higher than other mixed diet with two microalgal species (P < 0.05). Such change in the growth and survival of larvae fed on different microalgal species varies with larval development stages although a similar tendency on the growth, daily increment of shell length and survival in D shape, early umbone, umbone and late umbone stages were observed. In D shape stage the larvae fed on the feeding concentration (2 × 104 cells/mL/day) of mixed diet with four microalgal species showed the highest growth in shell length (125.8 ± 5.1 μm) and the feeding concentration (1 × 104 cells/mL/day) of mixed diet showed the highest survival (88.3 ± 4.9%) (P < 0.05). The growth of larvae tended to be higher, the higher the feeding concentration of diet but the lower survival of larvae showed, the higher feeding concentration of diet. Such change in the growth and survival of larvae fed on concentrations of mixed diet with four microalgal species varies with larval development stages although a similar tendency on the growth, daily increment of shell length and survival in D shape, early umbone, umbone and late umbone stages were observed. Daily feeding concentrations of 1 × 104- 2 × 104 cells/mL of microalgae mixed two species including C. simplex were very effective.
K. mikimotoi 배양체 (<TEX>$7,500cells\;ml^{-1}$</TEX>) 를 3가지 형태 (ICS, intact cell suspension; BCS, broken cell suspension; CFE, cell-free elutriate) 로 조작하여 4개 농도구배 (0, 10, 50, 100%) 로 전복치패 H. discus hannai에 노출 (온도, 13, <TEX>$18^{\circ}C$</TEX>) 하여 그 위해성을 생존율로 평가하였다. 또한, 두 적조 배양체 (C. polykrikoides와 A. affine) 를 동일형태, 농도구배 (생체량 기준), 온도에서 비교실험 하였다. 결과, K. mikimotoi는 북방전복에 어느 정도 피해를 유발하였고 (p < 0.05, 0.01), 기존 연구결과와 비교분석하였을 때, 피해기작은 세포막을 중심으로 한 독력에 의한 접촉 피해일 가능성이 있었다. 종적 비교에서, A. affine가 유의성 없이 약간 유해했다. 그러나 K. mikimotoi 독성은 strain과 성장환경에 따라 달라지며, 또한 배양체와 자연체와의 차이가 있어 본 연구결과를 일반화하기 위해서는 추가 연구가 필요한 것으로 판단되었다. 특히, 이 연구에서 실험구의 폐사시점이 대조구와 일치한다는 점에서 실험구 결과에 사육 스트레스가 부가되었음을 추측할 수 있었고, 이점은 향후 연구에서 고려할 사항으로 생각된다.
Karenia mikimotoi bloom is known to damage abalones via chemical toxicity, but the toxic mechanism remains unclear. In an attempt to gain an insight into its damage potential to abalone spats Haliotis discus hannai, the spats were exposed to 0, 10, 50, or 100% of 7,500 cells ml-1 K. mikimotoi in types of ICS (intact cell suspension), BCS (broken cell suspension) or CFE (cell-free elutriate) at 13 and 18℃, respectively. The spats were also exposed to corresponding type and dilution of 7,500 cells ml-1 Cochlodinium polykrikoides and 2,000 cells ml-1 Alexandrium affine which were equivalent to 7,500 cells ml-1 K. mikimotoi on the basis of TOC (total organic carbon). K. mikimotoi was proved to be damageable to the spats with damage potential not bigger than A. affine and C. polykrikoides. In algal type, ICS was most influential, particularly in lower dilutions (with an occasional significance of p < 0.01 or p < 0.05), suggesting that toxicity potential might be more associated with intact cell membrane. Overall, the spat damages of experimental trials were in concurrence with those of controls which were solely due to culture stress, suggesting that the culture stress might be an additional parameter influencing the spat damage and thus should be countered into consideration in future study.
The purpose of the present study is to know the reproductive characteristics of Octopus minor focusing on monthly variation of total weight and gonadosomatic index, fecundity, group maturity for management of the species resource effectively. Gonadosomatic index peaked June in females. The fecundity ranged from 89 eggs at 123.6 g to 200 eggs at 238.1 g of total weight. The relationship between total weight (TW) and fecundity (F) was F = 1.291TW0.908 (r2 = 0.85) and fecundity increased with total weight. The relationship between mantle length (ML) and total weight (TW) was TW = 1.939ML1.991 (r2 = 0.82) in female, TW = 1.566ML2.167 (r2 = 0.84). The total weight at 50% group maturity was estimated to be 158.0 g for sex combine.
본 연구에서는 신석기시대의 인천시 을왕동 패총에서 출토된 말백합의 패각에 나타난 윤문을 판독하여 성장식을 추정하고 현재의 말백합 개체군과의 성장을 비교하였다. 패총 출토 패각의 수는 총 86개체였다. 각 연령군별로 각장과 윤경 간에 대응성을 보였고, 각 윤문군이 비교적 뚜렷이 구분되어 윤문판독의 타당성이 확인되어 판독된 윤문을 연륜으로 간주하였다. 패총 출토 말백합의 윤문은 2-6개까지 확인되어 2-6세군으로 구성되었음을 알 수 있었다. 패총 개체군의 성장식은 <TEX>$SL_t
Growth-line analysis was carried out on the hard clam (Meretrix petechialis) collected from the Neolithic Eurwang-dong Shell Midden, Incheon, Korea, to reconstruct palaeoenvironment. The growth pattern of the midden specimens was compared to that of modern ones collected from Gimje, Jeonbuk, Korea. Growth curves for shell length fitted to the von Bertalanffy's growth curve were expressed respectively as follows : SLt = 139.3574[1-e-0.1049(t + 1.5160)] for the shell midden specimens; SLt = 104.2583[1-e-0.2277(t + 0.7499)] for the modern ones. The relationship between shell length (SL; mm) and shell height (SH; mm) was expressed by the following equations: SH = 0.8351 SL + 1.1480 (r2 = 0.959) for the shell midden specimens; SH = 0.8103 SL + 0.5145 (r2 = 0.991) for the modern ones. The result of t-tests for the differences in the regression coefficients and elevations of the growth curves for the two populations showed that slopes were not significantly different (p > 0.05). Considering that the overall growth curves for the two populations were not significantly different, it can be inferred that shell growth environments of the two areas were similar. Thus, we assumed that sea temperature near the shell midden was similar to that of present Gimje area.
- 두타산입술대고둥아재비 (M. junensis) 의 Arginine kinase 유전자는 1,074 bp, 아미노산 358 개로 이루어져 있다. - BLAST를 통해 얻은 13 종의 ArK 참고서열들과 두타산입술대고둥아재비의 ArK 서열을 다중서열정렬한 결과 ArK 특이 잔기가 보존되어 있음을 알 수 있었다. - MEGA7 소프트웨어를 활용하여 multiple alignment 한 후, Maximum-Likelihood 방법으로 Molecular phylogenetic analysis 를 수행한 결과, N. samarangae, A. kurodai, B. glabrata, S. libertinam, C. ebraeus, C. grata 와 같은 복족강들과 같은 분류군으로 묶이는 것을 확인 할 수 있었다. - 이러한 결과 ArK 유전자 서열은 계통분류학적 연구에 유용하게 활용될 수 있음을 확인할 수 있었다.
Arginine kinase gene belongs to phosphagen super family and is one of the transferases such as glycocyamine kinase (GK), lombricine kinase (LK), taurocyamine kinase (TK) and creatine kinase (CK) which are expressed in inverterbrates. Arginine kinase (ArK) is commonly called arginine phosphokinase, adenosine 5'-triphosphate, L-arginine, N-phosphotransferase and plays an important role in transporting intracellular energy and regulating phosphoric acid concentration. ArK is also known to play a critical role in arginine and proline metabolism. In this study, we conducted transcriptomic analysis of Mirus junensis using the Next Generation Sequencer and all the sequences containing arginine kinase were obtained by using BLASTx against NCBI NR database and PANM database. We confirmed 358 amino acid residues and 1,074 bp coding region of ArK gene. Using BLAST analysis, we collected 14 similar sequences of M. junensis ArK. Analsysis of dendrogram derived from multiple sequence alignment using clustalW engine of MEGA 7 program showed that it is most similar to Nesiohelix samarangae and belongs to Mollusk with Aplysia kurodai, Conus ebraeus. The ArK of M. junensis needs further investigation about immune system and physiological study.
Four unrecorded nudibranch species of Gymnodoris inornata Bergh, 1880, Gymnodoris amakusana (Baba, 1996), Madrella sanguinea (Angas, 1864), and Eubranchus inabai Baba, 1964 were collected from South Sea of Korea and redescribed with pictures.
One new land snail in the family Enidae, Mirus obongensis n. sp. is collected from Chuncheon-si, Kangwon-do on 24 May in 2000 and 21 August in 2012. This new species resembles to the other Enidae species in korea, but is easily distinguished by size difference in adult form. Including the present new species, the family Enidae contained 2 genera and 3 species in the Korea.
