• Parasites, Hosts and Diseases
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• 제44권1호
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• pp.81-86
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• 2006

Anisakiasis is a parasitic disease caused by ingestion of raw fish infected with anisakid larvae. Endoscopic changing patterns of submucosal lesions in chronic gastric anisakiasis have not been known yet. Here we report 4 cases of suspected gastric anisakiasis which were improved during follow-up periods without surgical treatment. The patients presented with abdominal pain, nausea and vomiting after consuming raw marine fish, and visited our gastroenterology outpatient department. Their endoscopic findings showed firm and yellowish submucosal masses accompanied with eccentric erosions. Histologic findings showed severe eosinophilic infiltrations. In blood tests, peripheral eosinophil counts and total IgE levels were elevated. We believed that all cases were caused by larval anisakid infections. The submucosal mass lesions disappeared during the follow-up periods of 2 to 4 mo.

• Molecules and Cells
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• 제23권3호
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• pp.379-390
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• 2007

We sequenced and characterized the complete mitochondrial genome of the Japanese fish tapeworm D. nihonkaiense. The genome is a circular-DNA molecule of 13607 bp (one nucleotide shorter than that of D. latum mtDNA) containing 12 protein-coding genes (lacking atp8), 22 tRNA genes and two rRNA genes. Gene order and genome content are identical to those of the other cestodes reported thus far, including its congener D. latum. The only exception is Hymenolepis diminuta in which the positions of trnS2 and trnL1 are switched. We tested a PCR-based molecular assay designed to rapidly and accurately differentiate between D. nihonkaiense and D. latum using species-specific primers based on a comparison of their mtDNA sequences. We found the PCR-based system to be very reliable and specific, and suggest that PCR-based identification methods using mtDNA sequences could contribute to the study of the epidemiology and larval ecology of Diphyllobothrium species.

• 한국수산과학회지
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• 제32권3호
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• pp.295-302
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• 1999

여수주변해역에서 부유성 어란과 치자어의 분포 조사가 1996년 8월, 11월과 1997년 1월, 4월에 실시되었으며 조사기간 중 어란은 4종, 치자어는 24종이 동정되었다. 어란은 멸치 (Engraulis japonicus)가 전체 어란 출현량의 $80.6\%$로 가장 높았고, 다음은 동갈양태류 (Callionymidae spp.) ($1.6\%$), 그리고 전어 (Konosirus punctatus)와 앨퉁이 (Maurolicus muelleri)는 $1.0\%$ 미만으로 출현량 비율이 매우 낮았으며 기타 미동정 어란은 $17.8\%$를 차지하였다. 치자어의 출현 종 수는 여름철에 17종으로 가장 많았고, 봄철에 4종으로 가장 적었다. 어종별 출현비율은 동갈양태류가 전체 치자어 출현량의 $25.7\%$로 가장 높았고 망둥어류 (Gobiidae spp.)가 $23.5\%$, 청보리멸 (Sillago japonica)이 $17.2\%$, 멸치가 $12.2\%$, 앞동갈베도라치 (Omobranchus elegans )가 $9.9\%$를 차지하였으며 그 외의 종은 모두 $2.0\%$ 미만이었다. 여수주변해역의 치자어는 망둥어류, 동갈양태류, 쥐노래미등의 연안성 어종과 비록 출현량은 작지만 제주도 주변해역을 통과하는 난류수의 영향으로 출현한 몽치다래류, 만새기, 자리돔 등과 같은 난류성종으로 구성되어 있었다.

• 한국수산과학회지
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• 제35권6호
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• pp.551-556
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• 2002

출산기에 임박한 조피볼락 암컷에 20mg/kg체중의 농도로 3,5, 3'-triiodo-L-thyronine $(T_{3}$)를 주사한 뒤, 출산 자어로의 호르몬 전이여부, 자어 성장과 활력을 조사하였다. 출산자어의 갑상선 호르몬을 분석한 결과,출산직후에 $T_{3}$구가 대조구 보다 높은 $T_{3}$농도를 나타냈으나, L-thyroxine $(T_{4}$)의 농도는 대조구와 유의차가 없었다. 그러나 실험기간 동안 어체내 모든 실험구의 감상선호르몬 농도는 $T_{3}$가 $T_{4}$에 비해 상대적으로 낮았고, 실험구별로는 $T_{3}$구가 대조구에 비해 높은 것을 알 수 있었다. 자어의 성장률은 대조구에 비하여 T,구에서 높았으며, 출산후 경과일수에 따라 직선적인 전장성장 경향을 나타냈다. 실험종료시 생존율은$ T_{3}$구의 자어가 대조구에 비해 높았으며, 유영활성에서도 $T_{3}$구의 자어가 대조구에 비해 유의하게 높았다. 출산직전 $T_{3}$ 모체주사는 외부영양원 섭취개시기의 자어성장 및 생리활성을 증진시키는 데 효과적인 것으로 나타났다. 이상의 연구결과로부터 출산전 모체주사를 통하여 외인성 $T_{3}$가 자어로 전이되며, 전이된 호르몬은 출산후의 자어의 초기 발달기 동안 생리적으로 긍정적인 작용을 할 것으로 추측된다.

• 한국패류학회지
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• 제23권2호
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• pp.181-187
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• 2007

A scanning electron microscopic study on the glochidium and glochidial encystment of Anodonta arcaeformis on the host fish Carassius auratus was conducted. The shape of the glochidium was apparently subtriangular and its average size was $270\;{\mu}m\;\times\;260\;{\mu}m\;\times\;145\;{\mu}m$. The glochidial shell valves were of the same size, kept together by a ligament that is 50.4 ${\mu}m$ in length and 5.5 ${\mu}m$ in width. Each of the glochidial shell valve had a long hook studded with many spines on the superior face. A large area of at the apex of the valve surrounding the base of the hook was provided with numerous small spines which became progressively smaller toward the periphery of the area. The glochidial shell valve consisted of two layers. The mantle cells line the glochidial shell valves and some of hair cells were observed. A larval thread was 2.3 ${\mu}m$ in diameter. In the artificial infection of the glochidia to one of the natural hosts, Carassius auratus, it took about three to four hours to encyst the glochidia with epithelial cells of the fish fins. The encystment method was the cell migration from the neighboring epithelial cells.

• 한국어류학회지
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• 제7권2호
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• pp.177-186
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• 1995

경상남도 삼천포시 신수도 연안의 치어류군집(稚魚類群集)의 계절변동(季節變動)을 연구하기 위하여, 1986년 10월부터 1987년 9월까지 매월, 2개의 정점에서 낭장망을 이용하여 치어(稚魚)를 채집하였다. 조사기간 동안 29과 44종이 출현하였다. 멸치, 베도라치, 까나리 및 붕장어 순으로 우점하였으며, 이 우점 4종은 총 개체수의 약 96.79%를, 총 생체량의 약 73.94%를 차지하였다. 치어류(稚魚類)의 종수, 개체수 및 생체량은 봄에 연중 높은 값을 나타내는 반면, 여름에 낮은 값을 나타내었다. 이는 봄에 우점 4종의 치어(稚魚)들이 많이 출현하기 때문이다. 개체수에 있어서 종다양도(種多樣度)(H')은 4월에 가장 높은 값을 나타내었고, 생체량에 있어서는 10월에 가장 높은 값을 나타내었다. 우점 4종은 각자 독특한 출현량의 계절변동(季節變動)을 나타내었다. 이들 종은 한 어종이 최대 출현량을 나타낸 후, 다른 어종이 최대 출현량을 나타내는 데는 약 2개월 정도 소요되었다.

• 한국발생생물학회지:발생과생식
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• 제19권4호
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• pp.181-187
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• 2015

Early life stage mortality in fish is one of the problems faced by loach aquaculture. However, our understanding of immune system in early life stage fish is still incomplete, and the information available is restricted to a few fish species. In the present work, we investigated the expression of immune-related transcripts in loach during early development. In fishes, recombination-activating gene 1 (RAG-1) and sacsin (SACS) have been considered as immunological function. In this study, the expression of the both genes was assessed throughout the early developmental stages of loach using real-time PCR method. maRAG-1 mRNA was first detected in 0 dph, observed the increased mostly until 40 dph. Significant expression of maRAG-1 was detected in 0 to 40 dph. These patterns of expression may suggest that the loach start to develop its function after hatching. On the other hand, maSACS was detected in unfertilized oocyte to molura stages and 0 to 40 dph. maSACS mRNA transcripts were detected in unfertilized oocytes, suggesting that they are maternally transferred.

• Fisheries and Aquatic Sciences
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• 제26권6호
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• pp.367-379
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• 2023

The rapid expansion of shrimp production requires a huge amount of protein sources from soybeans and wild-caught fishmeal; both are becoming a shortage. Meanwhile, catfish production and processing is a giant industry in Vietnam, which produce hundred thousand tonnes of protein- and lipid-rich by-products, annually. Using catfish by-products to gradually replace the traditional protein sources in shrimp aquaculture may bring triple benefits: 1) reducing pressure on wild fish exploitation for fishmeal, 2) reducing the environmental impacts of catfish by-products, and 3) increasing the value and sustainability of aquaculture production. In this study, we used catfish by-products to produce fish protein hydrolysate (FPH) and nano-hydroxyapatite (HA) as additives in feed for Pacific white shrimp (Litopenaeus vannamei). The supplement mixture of FPH and HA was added into the commercial diet (Charoen Pokphand Group [CP], 38% protein, and 6.5% lipid) to reach 38%, 38.5%, 40%, 43%, and 44% of the crude protein content. The survival and growth of shrimps were weekly assessed to day 55. The results showed that the shrimp growth was highest at 43% crude protein content in the feed as indicated by an increase of 124% and 112% in shrimp weight and length, respectively, compared to the commercial reference diet. No negative effects of adding the mixture of FPH and HA on the water quality were observed. Vibrio density was lower than 6.5 × 10³ CFU/mL, which is the lowest Vibrio density negatively affecting the shrimp growth and development. These findings indicate that the mixture of FPH and HA are promising additive components in feed for post-larval shrimp L. vannamei diets.

• 수산해양기술연구
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• 제58권4호
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• pp.326-333
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• 2022

To provide information needed for managing fish resources and protecting the ecosystem of Cheonsu Bay, bimonthly variations in species composition and abundance of fish eggs and larvae were investigated. The samples were collected by using bongo net at three different stations from February 2020 to December 2021. Fish eggs were divided into Engrualis japonicas and unidentified eggs, of which Engragulis japonicus accounted for 85.6% of the total eggs collected. A total of 21 species representing 17 families and 6 orders were collected. The three dominant species were Gobiidae spp, Thryssa hamiltonii and E. japonicus and these three species accounted for 74.1% in the total number of individuals. The number of species was highest in August, 2020 and lowest in February, 2020 and 2021; the number of individuals was highest in August, 2020 and lowest in February, 2020. Temporal changes in the abundances of pelagic eggs and larval fishes corresponded with temperature.

• 한국항해항만학회지
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• 제35권9호
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• pp.741-747
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• 2011

Ecological toxicity testing of the whole-effluent from the ozone ballast water treatment system was conducted as specified in the quality assurance project plans (QAPP). The growth inhibition test with microalgae, acute aquatic toxicity test with the Rotifer reproduction, toxicity test (or population growth) with the Rotifer, survival and growth toxicity test with larval fish and sediment toxicity test with amphipod were carried out to evaluate ecological toxicity on the movile test barge.