• 한국수산과학회지
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• 제38권3호
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• pp.158-163
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• 2005

This paper deals with the histology of the barbels of striped sea catfish, Plotosus lineatus (Thunberg). This fish have eight noticeable barbels of two pairs on their maxillary and mandibular. Each barbel is composed of an epidermis, dermis and a central rod of cartilage. The epidermis in the middle part of the maxillary barbel is thicker than those on other parts, and formed of stratified epithelium which contains many cutaneous taste buds and a few small club cells. Number of taste buds increase on the middle and posterior part of each barbel. The dermis consists of loose connective tissue fibers which encloses blood vessels and bundles of nerve fibers. The barbels of this fish can be categorized into stiff and flexible types and are accessory, feeding and sensory structures. Thus we substantiate that they are gustatory receptor organs for this fish.

• 한국어류학회지
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• 제29권2호
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• pp.89-93
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• 2017

최근 신종으로 발표된 동방자가사리 Liobagrus hyeongsanensis의 핵형 분석을 위해 경상북도 경주시 양북면 일대에서 암컷 10마리와 수컷 5마리를 채집하였다. 동방자가사리의 염색체 수는 2n=42이었으며, 핵형은 30개의 중부염색체와 12개의 차중부염색체로 구성되어 있었다. FN 값은 84였으며, 암수 간 성적이형과 배수체는 관찰되지 않았다. 동방자가사리는 퉁가리속의 자가사리, 섬진자가사리와 염색체 수는 같았으나 핵형에서 차이를 보였다. 이러한 핵형의 차이는 지리적 격리로 인한 로버트슨 전좌(Robertsonian rearrangement)와 관련 있는 것으로 생각된다.

• Journal of Applied Biological Chemistry
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• 제57권2호
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• pp.131-136
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• 2014

An attempt was made to assess metal ionic toxicity levels of different fishes in the polluted rivers viz., Buriganga and Turag. Fish samples collected from two polluted rivers were analyzed for the levels of metals such as Cd, Cr, Cu, Mn, Pb, and Zn in order to elucidate the status of these contaminants in fish meant for human consumption. The detected concentrations of Cr, Cu, Mn, and Zn ions in fish species collected from the polluted rivers were below the toxic levels and did not appear to pose a threat. Among the analyzed metals, Cd and Pb ions were detected above the permissible levels in liver and muscle tissues of stinging catfish (Heteropneustesfossilis), spotted snakehead (Channapunctata) and wallago (Wallagoattu) collected from the polluted rivers causing toxicity for human consumption. Stinging catfish (Heteropneustesfossilis) was the species found to highly bioaccumulate these metals. Fish species bioconcentrated appreciable amounts of Cd and Pb as toxic metals in the liver as compared to the muscle. Levels of these toxic metals varied depending on different tissues in fish species.

• 한국어병학회지
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• 제13권2호
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• pp.75-86
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• 2000

1998년 3월부터 2000년 4월까지 전라남 북도 및 충청남도 일원의 내수면 양식장에서 사육중인 뱀장어(Anguilla japonica)와 메기(Parasilurus asotus)를 무작위로 채집하여 아가미에서 국내 미기록종인 4종의 단생흡충류를 검출하였다. 검출된 단생흡충류는 모두 아가미 흡충으로서 뱀장어에서는 Pseudodactylogyrus bini(KIKUCHI, 1929), P. anguillae(YIN & SPROSTON, 1948), 메기에서 Ancylodiscoides infundibulovagina(YAMAGUTI,1941) 및 Ancylodiscoides sp.가 검출되었다.

• Genomics & Informatics
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• 제21권4호
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• pp.51.1-51.5
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• 2023

The genus Neoarius, known as marine catfish, is a group of the family Ariidae, composed of 10 species found in Oceania. None of the species in this genus have their mitochondrial genome described, which is highly valuable in phylogenetic and molecular evolution studies. For the present work, eight species from the Neoarius genus were selected: Neoarius utarus, Neoarius midgleyi, Neoarius graeffei, Neoarius leptaspis, Neoarius berenyi, Neoarius paucus, Neoarius pectoralis, and Neoarius aff. graeffei. DNA sequences of the eight species were obtained through the NCBI Sequence Read Archive (SRA) database, and the mitochondrial genomes were assembled using the NOVOplasty tool on the Galaxy platform, subsequently annotated with the MitoAnnotator tool. We then utilized the protein-coding genes from the mitogenomes to estimate the phylogenetic relationships within the group, including seven additional mitogenomes available in the NCBI. In all species, the mitochondrial genomes presented 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes, and 1 D-loop.

• Asian-Australasian Journal of Animal Sciences
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• 제27권8호
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• pp.1141-1149
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• 2014

The present study was conducted to investigate a supplemental effect of magnesium hydrogen phosphate (MHP, $MgHPO_4$) as an alternative phosphorus (P) source on growth and feed utilization of juvenile far eastern catfish (Silurus asotus) in comparison with three conventional P additives (monocalcium phosphate (MCP), dicalcium phosphate (DCP) and tricalcium phosphate [TCP]) as positive controls. A basal diet as a negative control was prepared without P supplementation and four supplemental P sources were added at the level of 2%. Five groups of 450 fish having mean body weight of 11.3 g following 24 h fasting after three week adaptation period were randomly distributed into each of 15 tanks (30 fish/tank). Fish were hand-fed to apparent satiety twice a day for 8 weeks. Fish fed MHP had weight gain (WG), protein efficiency ratio and specific growth rate comparable to those fed MCP. Fish fed MHP and MCP had feed efficiency (FE) significantly higher (p<0.05) than those fed DCP. Fish groups fed control and TCP showed the lower FE than the other groups which was significantly different (p<0.05) from those of fish fed the other diets. Survival rate was not significantly different (p>0.05) among treatments. Fish fed control had the lowest hematocrit, which was significantly different (p<0.05) from that of fish fed MHP. Fish fed MCP and MHP had plasma P higher (p<0.05) than fish fed the other diets. Relative efficiencies of MCP, DCP and TCP to MHP were found to be 100.5 and 101.3%, 92.0 and 91.6%, and 79.1 and 80.9% for WG and FE, respectively. P availability was determined to be 88.1%, 75.2%, 8.7%, and 90.9% for MCP, DCP, TCP, and MHP, respectively. Consequently, MHP recovered from wastewater stream showed that as an alternative P source its performance was comparative with MCP on growth and feed utilization of juvenile far eastern catfish.

• 한국어병학회지
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• 제6권1호
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• pp.1-10
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• 1993

발병한 양식 메기로 부터 vibrio속 균주를 분리하였다. 분리된 균주는 생물학적 생화학적 특성에 기초하여 동정한 결과 V. ordalii로 동정 되었다. 분리균은 glucose, lactose, maltose 와 salicine으로 부터 산을 생산 하였으며, arabinose, galactose, inocitol과 xylose는 이용하지 못하였다. 분리된 V. ordalii를 각각 KL-1, KL-2라 명명하였다. KL-l과 KL-2는 생리학적 특성이 유사하였다. 즉, pH 5-10, NaCl 0%~6.0%에서 발육하였으며, 또한 NaCl 7.0%, pH 10이상 그리고 pH5이하에서는 발육하지 않았다. KL-1 균주를 건강한 메기에 인공 감염시킨 결과 양식장에서 발병된 증상과 동일한 출혈성 궤양이 유발되었다. 감염 24시간 후에 나타난 흙은 반점은 접종 부위 주변에서 부터 확장되기 시작했으며, 감염 120시간 후부터는 배지느러미 부위까지 궤양이 확장되었다. 각각 온도에 따른 실험에서는 $25^{\circ}C$에서 폐사율이 70%로 나타났다. 약제 감수성 시험에서 KL-1 과 KL-2 균주는 모두 GM, K, N, S와 SxT에 감수성을 나타내었으나, CF 및 $L_2$와 VA에는 저항성을 나타내었다.

• 한국어류학회지
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• 제23권3호
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• pp.250-254
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• 2011

한국의 담수어류 중 짱뚱어, 큰볏말뚝말둥어, 말뚝망둥어, 미꾸리, 미꾸라지, 자가사리 등 모두 6종에서 공기로 호흡하기 위해 변형된 부속기관이 알려져 있다. 짱뚱어, 큰볏말뚝말망둥어, 말뚝망둥어, 자가사리 4종은 부족한 산소를 공기로부터 흡입하기 위해 호흡상피 (respiratory epithelium)를 갖는다. 이러한 호흡상피는 풍부한 모세혈관과 2종류의 선세포(점액세포와 곤봉세포-자가사리, 점액세포와 거대세포-짱뚱어) 또는 1종류의 선세포로 구성된 팽대세포 (말뚝망둥어와 큰볏말뚝망둥어)를 갖는다. 특히 거대세포 (swollen cell)는 상피세포의 팽대로 인해 형성된 거미줄 구조 (web-like structure)를 갖고 있다. 또한 짱뚱어의 진피성돌기 (dermal bulge)는 진피성 모세혈관이 매우 풍부하며, 지느러미 등의 부속지를 제외한 피부에 존재한다. 또한 미꾸리와 미꾸라지는 장 상피 (intestinal epithelium)에 모세혈관이 아주 풍부하게 존재한다.

• 한국수산과학회지
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• 제52권2호
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• pp.159-172
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• 2019

This study investigated the effects of dietary monobasic potassium phosphate (MKP) on the growth of the far eastern catfish Silurus asotus and four leafy vegetables in a hybrid biofloc technology aquaponic system. To an experimental diet containing 45% protein and 7% lipid, 1, 2, 3 or 4% MKP was added and was designated as MKP1, MKP2, MKP3, and MKP4, respectively. The optimum MKP levels were determined for the growth of fish and four leafy vegetables over 10 weeks. After the 10-week feeding trial, weight gain, feed efficiency, specific growth rate and protein efficiency ratio were higher in the fish groups fed MKP2 and MKP3 than in the other groups (P<0.05). The growth of the four leafy vegetables was also higher in the fish groups fed MKP2 and MKP3. Water quality [dissolved oxygen, pH, water temperature, electrical conductivity, turbidity, total ammonia nitrogen (TAN), $NO_2-N$, $NO_3-N$ and $PO_4-P$] was measured six times a week using a portable water quality meter and reagent measurements. The TAN (4.58-20.40 mg/L), $NO_3-N$ (24.12-52.40 mg/L) and $PO_4-P$ (20.38-48.48 mg/L) levels increased with time, while the $NO_2-N$ level remained below 0.1 mg/L throughout the study.

• 한국수산과학회지
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• 제32권1호
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• pp.56-61
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• 1999

참메기, Silurus asotus를 대상으로 수온 ($15^{\circ}C,\;20^{\circ}C,\;25^{\circ}C$ 및 $30^{\circ}C$)과 광주기 (24L:0D, 12L:12D 및 0L:24D)에 따른 산소 소비량의 변화를 연속적인 컴퓨터 모니터링 시스템을 이용하여 조사하였다. 평균 무게 280g의 참메기의 산소 소비량은 수온의 증가에 따라 증가하였고, $15^{\circ}C$에서 $35.2\~96.4mg\;O_2/kg$ fish/hr, $20^{\circ}C$에서$78.6\~127.9mg\;O_2/kg$ fish/hr, $25^{\circ}C$에서$120.1\~231.7mg\;O_2/kg$ fish/hr, $30^{\circ}C$에서 $197.5\~352.3mg\;O_2/kg$ fish/hr으로 나타났다(p<0.05). 광주기에 따른 산소 소비량은 암기 조건에서 보다 명기 조건에서 산소소비량이 더 높게 나타났다. 또한, 24L:0D와 12L:12D와 비교하여 0L:24D에서 평균 산소 소비량이 낮게 나타났다(p<0.05). 산소 소비량의 최대값과 최소값의 차이는 수온이 상승함에 따라 증가하였고, 12L:12D에서 가장 큰 것으로 나타났고, 새벽녁과 저녁 무렵에 산소 소비량의 급격한 변화를 나타내었다. 특히, 12L:12D의 조건에 두었을 때 명기와 암기에 대한 뚜렷한 반응을 보였다.