• 한국어류학회지
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• 제28권3호
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• pp.175-178
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• 2016

전라북도 남원시 식정동에서 채집한 한국 고유종인 섬진자가사리를 암, 수 각각 9마리와 8마리의 핵형 분석을 실시하였다. 섬진자가사리의 염색체 수는 2n=42로 조사되었고, 핵형은 28 metacentric과 14 submetacentric으로 이루어져 있었으며 FN은 80이었다. 이번 결과에서 배수체와 암수 간의 성적이형은 발견되지 않았다. 섬진자가사리는 근연종들과 염색체 수는 같았으나, 핵형에서는 차이를 보였다.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2000년도 춘계수산관련학회 공동학술대회발표요지집
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• pp.233-234
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• 2000

Formalin, 37% formaldehyde, has been employed as a chemical for controlling ectoparasites and aquatic fungi responsible for infectious fish of diseases in hatcheries and culture facilities (Roberts, 1978; Schnick, 1991; Rach et al., 1997). Regarding the commercial usage of formaldehyde in the aquaculture industry, the U.S. Food and Drug Administration (FDA) approved three commercial products as parasiticides in a species-specific manner: Paracide-F and Formalin-F for bluegill, catfish, largemouth bass, salmon, and trout and Parasite-S for all finfish (FDA, 1998). Withdrawal time for these products was legally zero when used as permitted under the regulations. With the increased production of cultured fish in Korea, such as olive Hounder Paralichthys olivaceus and black rockfish Sebastes schlegeli, application of formalin to diseased fish has become more frequent. Moreover, there is still some concern about environmental exposures caused by effluents from fish culture facilities. The purpose of the present study was to evaluate residues in fish resulting from therapeutic usage of formalin in the aquaculture industry and to document the rate of disappearance of formaldehyde in seawater treated with formalin. (omitted)

• Interdisciplinary Bio Central
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• 제2권2호
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• pp.5.1-5.9
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• 2010

Flavobacterium columnare (F. columnare), the dermotropic Gram negative yellow pigmented bacteria was isolated from different sites of skin ulcerations in the Nile tilapia (Oreochromis niloticus) and Nile catfish (Clarias gariepinus) collected from an earthen pond located at an aquaculture station in Sharkiya Province, Lower Egypt during an acute episode of mass kills during the early summer of 2009. An acute infection with F. columnare was behind the emergent event of mass mortalities among both populations. Many of the Nile tilapias exhibited typical signs of hole - in- the head like lesions from which F. columnare together with the myxosporean spore, Myxobolus tilapiae (M. tilapiae) were retrieved. Most of the cohabitating infected Nile catfishes exhibited severe form of saddle back like ulcer. The identities of the retrieved isolates were confirmed using morphological, biochemical and molecular tools. The research lead us to conclude that the two diverse etiological agents (F. columnare and M. tilapiae) under the triggering effect of the abrupt change in the water quality measures (abrupt rise in the water temperature, ammonia, pH, sharp decrease in dissolved oxygen) have synergized together to induce the above mentioned pathology with the consequent reemergence of fish mass mortalities.

• 한국어병학회지
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• 제19권3호
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• pp.227-233
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• 2006

Olive flounder immunoreceptor DAP10 homologue cDNA was cloned from a peripheral blood lymphocytes (PBLs) cDNA library. The length of the olive flounder DAP10 cDNA is 473bp and it contains an open reading frame of 234bp. The predicted polypeptide sequence is 78 amino acids, consisting of a 22-amino acid leader, an 11-amino acid extracellular domain, a 21-amino acid transmembrane segment, and a 24-amino acid cytoplasmic domain. The amino acid sequence of olive flounder DAP10 has 56%, 50%, 32%, 31%, and 31% sequence identity with zebrafish DAP10, catfish DAP10, cattle DAP10, rat DAP10 and Monkey DAP10, respectively. Olive flounder DAP10 has a conserved aspartic acid in the transmembrane domain and a phophatidylinositol-3 kinase-binding site (YxxM/V) in the cytoplasmic region. Genomic organization reveals that olive flounder DAP10 comprises five exons and four introns. A phylogenetic analysis based on the deduced amino acid sequence grouped the olive flounder DAP10 with other species DAP10. In RT-PCR analysis, DAP10 transcripts were detected predominantly in PBLs, kidney, spleen and intestine.

• 한국어병학회지
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• 제22권3호
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• pp.343-352
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• 2009

Natural-killer-cell-enhancing factor (NKEF) belongs to the newly defined peroxiredoxin (Prx) family. It was originally isolated from human erythroid cells. The black rockfish NKEF cDNA was identified through the expressed sequence tag (EST) analysis of PBLs libraries. The full-length NKEF cDNA was 1433 bp long and contained an open reading frame (ORF) of 594 bp that encoded 198 amino-acid residues. The 5' UTR had a length of 39 bp, and the 3’UTR 800 bp. The deduced amino-acid sequence of the black rockfish had a density 93.4, 92.9, 87.8, 85.8, 84.8, 83.8, 80.3, 79.7, 77.2, and 75.2% that of the pufferfish, olive flounder, channel catfish, zebrafish, chicken, common carp, Myotis lucifugus, cattle, human PrxI, rat PrxI, human NKEF-A, and Xenopus tropicalis, respectively. The NKEF gene was expressed in all the tissues of the black rockfish. The RT-PCR indicated that the NKEF transcripts were predominantly in the spleen and gill, less dominantly in the PBLs, head kidney, trunk kidney, and liver, and least in the intestine and muscles. This is the first report on the existence of the NKEF-A gene in black rockfish.

• 한국양식학회지
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• 제16권1호
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• pp.51-58
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• 2003

The first Indian transgenic fish was generated in 1991 using borrowed constructs from foreign sources. To construct transformation vectors for the indigenous fishes, growth hormone genes of rohu (r-CH), Labeo rohita and catfish, Heteropneustes fossilis were isolated, cloned and sequenced; their fidelity was confirmed in prokaryotic and eukaryotic systems. A vector was constructed with grass carp b-actin promoter driving the expression of r-GH. Rohu eggs are large. fragile and swell 2~3 times. when fertilized. Hence they were amenable only for electroporated sperm-mediated gene transfer. Accordingly, the sperm electroporation technique was standardized to ensure 25% hatchling survival and 37% Presumptive transgenics without suffering any deformity. Southern analysis confirmed genomic integration in 15% of the tested individuals (Ti) belonging to family lines 2 and 3: another 25% of the Juveniles (Te) were also proved transgenic but with the transgene persisting extrachromosomally for longer than 1 to 2 years. perhaps due to the presence of replicon in the vector. Transgenics belonging to different family lines grew 6~8 times faster than the respective controls. Difference in growth trends of Ti and Te within a family line was not significant. In the Ti family 3 remarkable growth acceleration was sustained for a period longer than 36 weeks but in those of family 2, it gradually decreased. All transgenic fishes including the rohu converted the food at a significantly higher efficiency. Barring the transgenic mudloach, all the other transgenic fishes consumed food at significantly reduced rate.

• 한국해양바이오학회지
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• 제3권1호
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• pp.31-37
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• 2008

Off the 1,572 km long coastline of Namibia lies known as the Benguela upwelling system, a very rich source of marine life supporting traditional and modern forms of fishery. Commercial fishing and fish processing is one of the fastest-growing sectors of the Namibian economy in terms of employment, export earnings, and contribution to GDP. The fishing industry has grown to the extent that it is currently Namibia's second biggest export earner of foreign currency after mining (90% of national output is marketed for export). In 2005, Namibia harvested about 552,164 tonnes of fish. The final value of processed products (export value) that year was around US$ 376.0 million. Besides the marine captured fisheries, Namibia also has a small but vibrant aquaculture sector. Inland captured fisheries exist in the north-east and north-west of Namibia where as commercial freshwater aquaculture of tilapia and catfish is also undertaken. The inland fisheries are mainly subsistence based and typically labour intensive, with low catch per unit effort. However the subsistence fisheries from these regions play a significant role in the lives of rural community. The domestic market for marine fish products is extremely limited due to the small size of the population (2 million). The fishing industry is a source of considerable employment for many Namibians. Huge potential to increase production exists in Namibia, unpolluted high quality marine waters, high natural primary productivity of the seawater, availability of inexpensive fish by-products from established fish processing sector for inclusion in wet aqua-feeds and well-established processing, packaging and marketing systems due to the marine capture fisheries that can be adopted for aquaculture purpose.

• 한국어류학회지
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• 제18권1호
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• pp.20-26
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• 2006

동자개(Pseudobagrus fulvidraco), 대농갱이(Leiocassis ussuriensis) 및 이들간 잡종의 염색체수는 모두 2n=52로 동일하였으나, 핵형은 서로 상이하여 동자개가 22 metacentrics (M)+22 submetacentric (SM)+8 acrocentric (A) chromosome으로, 대농갱이는 22M+14SM+16A, 그리고 잡종은 22M+18SM+12A로 구성되어 있었다. 잡종은 동자개, 대농갱이 각각의 반수체로 구성되어 있었다. 적혈구 세포 및 핵의 크기, 표면적 및 체적을 측정한 결과 유도된 잡종은 양친의 중간값을 나타내었다. 동자개, 대농갱이 및 잡종의 DNA 함량을 측정한 결과, 동자개는 2.06 pg/cell, 대농갱이는 2.09 pg/cell, 동자개와 대농갱이 잡종은 2.08 pg/cell로 나타나, 잡종의 DNA 함량은 양친의 중간값으로 나타났다.

• 한국어류학회지
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• 제34권3호
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• pp.153-159
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• 2022

한국 고유종 눈동자개 Pseudobagrus koreanus 후각기관과 서식처 환경, 생태적 습성의 연관성, 유연종들과의 특징 비교를 위해 실체현미경, 광학현미경, 주사전자현미경하에서 형태 및 조직학적 실험을 진행하였다. 후각기관의 외부 형태는 주둥이 끝에 위치한 튜브형의 전비공과 비수염(nasal barbel) 뒤쪽 기부에 위치한 틈새형(slit)의 후비공으로 구성된다. 내부의 비강에는 비선(raphe)을 중심으로 방사형 또는 서로 평행하게 배열된 많은 수의 후판으로 구성된 로제트 구조를 나타낸다. 후판에는 후감각뉴런, 지지세포, 기저세포와 림프구, 형질세포로 구성된 감각상피와 층상상피세포, 점액세포, 림프구로 구성된 비감각상피가 확인되었다. 그중 1) 41~43 (n=20)의 후판, 2) 림프구, 형질세포, 3) 중성 다당류 점액을 보유한 점액세포는 다소 정체된 유속의 서식처 환경, 후각 의존적인 야생성의 생태적 습성, 다른 유연 메기목 어류들과 비교되는 분류학적 특징으로 사료된다.

• 대한환경공학회지
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• 제33권7호
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• pp.492-500
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• 2011

육상양식장에서 항생제에 대한 내성을 가진 균을 분리하여 다양한 항생제에 대한 내성특성을 확인하고, 전자빔의 조사에 따른 내성균의 항생제 내성 특성변화와 살균효능에 관한 연구를 수행하였다. 메기, 송어, 뱀장어, 미꾸라지양식장의 배출수에서 분리된 균주 중 Aeromonas sp., Citrobacter sp., Bacillus sp., Marinobacter sp., Pantoea sp., Pseudomonas sp., Enterobacter sp.가 다제내성균으로 확인되었다. 양식장 배출수에서 분리한 균주 중 한가지의 항생제 내성을 가지고 있는 균은 41.7%이며, 2가지 이상의 항생제 내성을 가지고 있는 균은 58.3%로 나타났다. Quantitative Structure Analysis Relationship (QSAR) model에 의한 평가는 실험값과 매우 유사하여 독성 평가의 간접적인 지표로 이용될 수 있음을 알 수 있었다. 항생제 내성균에 대해 전자빔을 조사한 결과 1 kGy 이내의 선량에서 살균효율이 99.9%로 강한 살균력을 확인할 수 있었다.