• 한국양식학회지
• /
• 제15권1호
• /
• pp.7-13
• /
• 2002

Since 1993, the White Spot Syndrome Virus (WSSV) disease occurred in China among cultured shrimps resulting in mass mortality. Epizootiological surveys undertaken during the outbreak period of 1993-1994 indicated that all stages of Penaeus chinensis, P. japonicus and P. monodon were infected. Consequent to the transport of contaminated shrimp seedlings and seawater, the disease spread all over the farms of China. The disease was more rapidly transmitted at temperatures above $25^{\circ}C$. Challenge experiments showed the causative agent was highly virulent. White spots appeared on the carapace of both span-taneous and experimentally infected shrimps. Moribund shrimps contained turbid hemolymph, hypertrophied Iymphoid organ and a necrotic mid-gut gland. Electron microscopy showed the presence of viral particles in the gills, stomach, lymphoid organ, and epidermal tissue of the infected shrimp. The visions were slightly ovoid with an envelope and averaged 350 $\times$ 150 nm; nucleocapsids measured 375 $\times$ 157 nm. With discontinuous sucrose gradient of 35, 50 and 60% (w/v), the virus was separated from hemolymph of the infected shrimp. The estimated molecular weight of genomic DNA was 237 Kb with EcoR I, 247 Kb with Hind III and 241kb with Pst I. A total of 9 hybridoma colones secreting monoclonal antibodies (MAbs) were produced from mouse myeloma and spleen cells immunized with WSSV. The immunofluorescence assay of gill tissue showed that the MAbs reacted with diseased but not with healthy shrimp. The MAbs belonged to IgGl, IgG2b subclass and IgM class, all with kappa light Immune-electron-microscopy with colloidal gold marker showed the presence of 5 MAbs epitopes on the envelope and one on the capsid of the virus. Baculoviral mid-gut gland necrosis showed the specificity of the MAbs produced. For diagnosis 5 different methods were selected. Using Kimura primers for PCR, or MAbs for immunoblot, ELISA or FAT method, in situ hybridization was carried out to show the gene. All these methods detected WSSV in the organ samples of the diseased shrimp but not in healthy one.

• Fisheries and Aquatic Sciences
• /
• 제9권4호
• /
• pp.153-159
• /
• 2006

The ark shell (or 'blood clam') Scapharca broughtonii is a filter-feeding bivalve that has red blood and inhabits waters approximately 10m in depth off the southern coast of South Korea. This study was part of a larger research project investigating the causes of death and restoration of shellfish resources, which are important aquaculture products in South Korea. We examined physiological responses related to survival, respiration, excretion, and amino acid changes as a result of changes in salinity. The 9-day median lethal salinity ($LS_{50}$) was 16.5 psu with confidence limits of 14.9-18.1 psu. At $25^{\circ}C$, the oxygen consumption and ammonia-nitrogen excretion rates were increased with decreases in salinity. Although the osmolality of individuals was acclimated within 2 h at 26.4 psu and 12 h at 19.8 psu, it took more than 5 days at a salinity of 13.2 psu, whereas no individuals acclimated and all died at a salinity of 6.6 psu. Of the amino acids present in the blood, taurine and alanine increased in response to decreased salinity. Tissues of the gill and the mid-gut gland were affected by decreasing salinity. These data will provide important fundamental information for examining the causes of mass mortality of shellfish in the summer.

• International Journal of Industrial Entomology and Biomaterials
• /
• 제33권2호
• /
• pp.113-120
• /
• 2016

Bombyx mandarina is widely accepted as ancestor of B. mori. Silkworms are served as well-characterized models for understanding the mechanism for the genetic regulation of development. In this study, we performed RNA-Seq analysis to examine tissue-expression of gloverin isoforms of the silk-gland, mid-gut, and fat body in B. mandarina. BLAST analysis revealed that four gloverin isoform gene sequences of B. mandarina were highly similar to B. mori. To identify the difference between two species, the expression profile of gloverin was measured by semi- RT-PCR analysis. The specific expression of gloverin isoform genes was observed mainly in the fat body from B. mori but not B. mandarina. However, all of tissues in the wild-type silkworm could induce the upregulation of compared with the B. mori. To validate the sudden increase in gloverin gene expression in the mid-gut tissue of B. mandarina, we were using qRT-PCR. Relative mRNA expression rate of gloverin at the wild-type silkworm was much higher than domestic silkworm. Comparative genomics between domesticated and wild silkworms showed different tissue-expression levels in some of immune related genes. These results are suggesting a trend toward decreasing immunity related genes expression during domestication. Further studies are needed to elucidate the silkworm domestication and an invaluable resource for wild silkworm genomics research.

• 한국수산과학회지
• /
• 제40권2호
• /
• pp.63-67
• /
• 2007

To prevent food poisoning after ingesting sea snails containing tetramine we measured the tetramine $[(CH_3){_4}N^+]$ contents of sea snails from the Korean coast using both ion chromatography (IC) and spectrometry. In total, 177 sea snails were collected from the east (Pohang, 19 species, 95 individuals), the west (Gunsan, 4 species, 46 individuals), and the south (Tongyeong, 8 species, 36 individuals) coasts. The working solution of tetramine standard for IC and the tetramine extract from the salivary gland of Neptunea arthritica cumingii were very stable for one month at $18^{\circ}C,\;4^{\circ}C$, and room temperature. The tetramine content was high in the salivary gland of Heptunea species such as N. intersculpta $(9,813{\mu}g/g)$, N. arthritica $(8,240{\mu}g/g)$, N. arthritica cumingii $(6,967{\mu}g/g)$, N. eulimata $(6,946{\mu}g/g)$, N. constricta $(5,965{\mu}g/g)$, and N, amianta $(4,502{\mu}g/g)$. The mid-gut gland and muscle contained small amounts of tetramine. The tetramine content was highest in the autumn, but no clear regional variations were observed.

• 한국수산과학회지
• /
• 제40권1호
• /
• pp.16-23
• /
• 2007

Nonylphenol (NP) is an estrogen-mimicking compound or xenoestrogen. This study investigated the effects of nonylphenol on the reproductive status of the equilateral venus Gomphina veneriformis. The experiment lasted 24 weeks, Experimental groups consisted of a control and three nonylphenol exposures ($1.0,\;2.5,\;and\;5.0\;{\mu}g\;NP/L$). Mortality did not differ significantly between the control and the exposure groups. The sex ratio (F:M) was 1:1 in nature and 1:1.03 in the control group. However, it changed to 1:3.5 with $5.0\;{\mu}g\;NP/L$ exposure. Gonad maturity in females was higher in the nonylphenol exposure groups than in the control group. By contrast, in males, it was lower in the nonylphenol exposure groups. Intersex individuals constituted 0% in nature, 3.08% in the control group, and 23.6% in the group exposed to nonylphenol, with female characteristics more prevalent than male. As the concentration of nonylphenol increased, the accumulation of lipofuscin increased in the mid-gut gland.

• 한국양식학회지
• /
• 제17권3호
• /
• pp.215-220
• /
• 2004

돌돔, Oplegnathus fasciatus의 소화관은 식도, 위, 장 및 항문이 일련의 관을 이루고 있고,전체적으로 지방 덩어리가 싸고 있다. 어체 체장에 대한 식도에서 항문까지의 소화관 길이의 비(relative length of gut: RLG)는 일반적인 잡식성 어류와 비슷한 평균 1.78 (n=30)의 값을 가진다. 식도는 근육층이 잘 발달되어 있으며, 점막주름의 상피층은 입방상피 또는 원주상피로 구성되고 상피세포 사이에는 다수의 산성 점액분비세포들이 분포하며, 상피세포의 정단부에서 미세융모의 관찰은 어렵다. 위의 근육층은 외부로부터 종주근, 환상근층으로 구성된다. 위의 점막주름은 규칙적인 형태로서 상피층에는 pit, 상피 및 위선이 아주 잘 발달되어 있으며, 점막상피 세포질의 정단부에서는 영양분 흡수계통의 물질들이 관찰된다. 50∼60개의 유문수를 가지는 돌돔 유문수의 점막상피층에서는 원주형의 상피세포와 중성의 점액분비세포들이 관찰되며, 상피세포의 정단면에는 미세융모가 발달되어 있다. 장의 점막상피층에서는 원주상피세포와 중성과 산성의 점액분비세포들이 관찰되며, 종주근층의 두께가 전장, 중장, 후장으로 갈수록 두꺼워진다. 산성의 점액분비세포의 출현빈도는 중장부에서 가장 발달된 양상을 보이며 후장부로 갈수록 감소하는 경향을 보인다.

• 한국수산과학회지
• /
• 제44권1호
• /
• pp.45-49
• /
• 2011

As a first step toward identifying a new method for testing sea snail tissue for toxins, and thus prevent food poisoning due to the ingestion of contaminated snails, we measured the tetramine [$(CH_3)_4N^+$] contents of sea snails from the Korean coast using both liquid chromatography-tandem mass spectrometry (LC-MS/MS) and ion chromatography. For tetramine tested, good linearity ($r^2$ = 0.9996) was observed between the amounts in the injected samples and the peak areas of standard toxins, which ranged from 0.1 to 100 ng. The recovery (%) of tetramine from spiked tissue and mid-gut gland samples ranged from 84.0 to 95.3%. The quantitative results for tetramine using this method were in good agreement with the theoretical values. LC-MS/MS has both high sensitivity and selectivity, which makes it possible to measure trace quantities of tetramine in samples.

• International Journal of Industrial Entomology and Biomaterials
• /
• 제16권1호
• /
• pp.21-27
• /
• 2008

The expression of heat shock protein genes (Hsp 70, Hsp 40, Hsp 20.8 and Hsp 20.4) against thermal stress in silkworm Bombyx mori was performed through semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR). Upon exposure of silkworm to two temperature regimes ($38^{\circ}C$ and $42^{\circ}C$), significant change in the expression of Hsp gene was observed as compared to the control. Hsp 70 and Hsp 40 showed increased expression than the small heat shock protein genes Hsp 20.8 and Hsp 20.4. The Hsp 70 showed increased expression during the recovery period as compared to 1 hr thermal treatments ($38^{\circ}C$/1 hr and $42^{\circ}C$/1 hr). Whereas, Hsp 40, Hsp 20.8 and Hsp 20.4 genes showed higher expression level at initial stages that later gradually decrease during recovery period. Tissue specific expression of Hsp 70 showed variation in the level of expression amongst the tissues. The mid gut and fat body tissues showed higher expression than the cuticle and silk gland tissue. The Hsp 70, Hsp 40 gene expression was analyzed in thermotolerant (Nistari) and thermo susceptible silk worm strain (NB4D2) and results showed significant variation in their expression level. The Nistari showed higher expression of Hsp 70 and Hsp 40 genes than the NB4D2. These findings provide a better understanding of cellular protection mechanisms against environmental stress such as heat shock, as these Hsps are involved in an organism thermotolerance.

• 한국수산과학회지
• /
• 제32권5호
• /
• pp.642-648
• /
• 1999

감성돔, Acanthopagrus schlegeli의 소화관은 식도, 위, 장, 항문 그리고 위의 유문부 말단에서 유래한 4$\~$5개의 맹낭 형태인 유문수로 이루어져 있었다 어체 체장에 대한 식도에서 항문까지의 소화관 길이의 비 (RLG: relative length of gut)는 1.04(n=10)였다. 소화관의 조직층은 장막, 근육층, 점막하층, 점막층으로 구성되는데, 점막하층의 발달은 전체적으로 매우 미약했다. 식도 점막주름의 형태는 규칙적인 분지형이었으며, 점막근층은 아주 잘 발달되어 있었다. 점막상피층은 입방형 또는 원주형 상피세포와 점액분비세포로 구성되며, 상피세포의 자유면에서 미세융모의 관찰은 어렵다. 위점막주름의 형태는 규칙적인 미분지형이며, 위의 근육충과 점막근층은 잘 발달되어 있었다. 점막충의 표면상피에서는 미세융모가 관찰되며, 위선과 분비과립은 체부에서 가장 잘 발달되어 있었다 유문수와 장의 점막주름은 불규칙한 분지형이다 장은 점막주름의 길이와 조직학적인 특징에 의해 전장부, 중장부, 후장부의 구분이 가능하였다. 유문수와 장의 선조연과 배상세포는 후장부에서, 영양분흡수세포는 중장부에서 가장 발달된 양상을 보였다.

• 한국수산과학회지
• /
• 제3권1호
• /
• pp.27-32
• /
• 1970

살아 있는 개량조개 속에 들어 있는 토사의 배출에 대하여 실험한 결과를 요약하면 다음과 같다. 1) 토사는 주로 입수관 및 출수관 주변, 아가미 주변, mantle주변 그리고 중장선을 위시한 소화 기관 속에 존재하였다. 그리고 소화기관 속에 들어 있는 모래의 크기는 $180\times10\mu\~550\times200\mu$정도의 극히 작은 것들이었다. 2) 시료를 밑바닥에 깔아 놓은 것과 중간층에 수하시킨 것 그리고 단층으로 깔든지 또는 수하시킨 것과 두껍게 깔든지 또는 수하시킨 것 사이에 토사의 배출에 있어 뚜렷한 차이는 찾아 볼 수 없었다. 3) 개량조개는 처음 1시간 정화시키면 약 $50\%$의 토사를 배출하며, $22\~26$ 시간만에 배출물의 양이 거의 일정한 값에 도달하지만, 배출물 속에 토사가 배출되지 않을 때까지는 약 42시간 소요되었다. 4) 토사의 배출에 미치는 PH의 영향을 보면 개량조개가 살고 있는 환경 해수보다 약 1정도 높은 쪽(pH 8.75)이 빨랐다. 5) 토사의 배출에 미치는 온도의 영향은 개량조개가 살고 있는 환경 해수의 온도 때가 온도를 더 높였을 때보다 토사의 배출이 빨랐다. 6) 토사의 배출에 미치는 염분 농도의 영향은 개량조개가 살고 있는 환경 해수의 염분 농도($30.61\%_{\circ}$)보다 약 배로 묽은 쪽($15.14\%_{\circ}$)이 배출이 빨랐다.