• 한국어병학회지
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• 제6권1호
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• pp.21-55
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• 1993

해산어에서 넙치, 조피볼락, 담수어에서 비단잉어와 뱀장어의 4 어종에서 과망간산칼리에 의한 아가미의 조직변화를 관찰하였다. 해산어는 담수어에 비해 과망간산칼리에 더 민감하며, 1ppm의 저농도에서도 아가미의 조직변화가 일어났다. 뱀장어는 비단잉어보다 과망간산칼리에 대한 저항성이 더 높았다. 특히 뱀장어에서는 과망간산칼리에 노출된 어류의 아가미에서 점액세포의 증가가 두드러졌다, 사육수에서는 지하수에서보다 과망간산칼리의 영향이 훨씬 감소하는데, 이 차이가 유기물질의 양에 의한 것임은 사료농도별로 한 실험에서 확인되었다. 또한 용존산소에 따라서도 과망간산칼리의 효력이 영향을 받는다.

• Applied Microscopy
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• 제41권1호
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• pp.13-20
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• 2011

바다빙어목(Osmeriformes), 바다빙어과(Osmeridae)에 속하는 빙어(Hypomesus nipponensis)의 성숙란 난막구조를 광학현미경과 전자현미경을 이용하여 관찰하였다. 빙어의 성숙란은 두 개의 난막으로 둘러싸여 있었으며 바깥쪽 난막의 외층은 한 층의 여포세포가 분포하고 있었고 안쪽의 난막 바깥쪽은 호염기성을 나타내는 구조물들이 배열하고 있었다. 난막의 단면을 투과전자현미경으로 관찰한 결과 두 개의 난막 중 바깥쪽 막은 전자밀도가 균일한 한 층으로 되어 있었고 안쪽막은 전자밀도가 높은 6층이 전자밀도가 낮은 5층에 의해서 분리되어 층상구조를 하고 있었다. 주사전자현미경으로 관찰한 결과 바깥쪽 막은 홈들이 관찰되었고 안쪽막 표면은 무정형의 구조물들이 산재하고 있었다. 또한 동물극 쪽에 한 개의 난문이 관찰되었다. 이상과 같이 빙어의 성숙란은 지금까지 보고된 경골어류의 경우 한 개의 난막으로 둘러싸여 있는데 비해서 두 개의 난막으로 둘러싸여 있다는 것은 매우 중요한 빙어의 종특이성을 나타내며 난막의 미세구조적 특징들은 종을 분류하는 데 이용될 수 있다.

• Asian-Australasian Journal of Animal Sciences
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• 제11권2호
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• pp.196-200
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• 1998

The proximate composition of viscera of six fish species viz., Catla catla, Labeo, rohita Cirrhina mrigala, Hypophthalmichthys molitrix, Ctenopharyngodon idella and Cyprinus carpio under the influence of artificial feed $(T_1)$, broiler manure $(T_2)$, buffalo manure $(T_3)$, N:P:K (25:25:0 $T_4$) and control pond $(T_5)$ has been studied on final harvest after the end of experimental period of one year. The overall comparison of six fish species under five different treatments showed that Cyprinus carpio remained the best for visceral total protein contents. The maximum visceral protein content was recorded in fishes under $T_2$ except Cirrhina mrigala, while the minimum under $T_5$. The comparison of five treatments showed that maximum (6.69) percentage of fat in viscera of fish was recorded under $T_2$, closely followed by $T_4$ while minimum (4.89) under the effect of $T_5$. Among the six fish species under five treatments Cyprinus carpio showed maximum accumulation/deposition of total fats in viscera.

• Toxicological Research
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• 제25권4호
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• pp.231-235
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• 2009

Trace lead detection for cyclic voltammetry (CV) and square-wave (SW) stripping voltammetry was performed using mercury immobilized onto a carbon nanotube electrode (HNPE). Using the characteristics of mercury and the catalytic carbon nanotube structure, a modified technique, the $0.45{\mu}g/l$ detection limit of lead ion was attained. The developed method can be applied to pond water, fish tissue, plant tissue, and in vivo direct assay.

• Interdisciplinary Bio Central
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• 제2권4호
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• pp.10.1-10.5
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• 2010

Total aflatoxin and ochratoxin were detected in 3 naturally contaminated fish feed samples using immune-affinity method. The results revealed that the average levels of aflatoxins in the 3 examined samples were (15, 22 and $12\;{\mu}g/kg$) respectively while the average levels of ochratoxins were (15, 6 and $6\;{\mu}g/kg$). The results of determination of the effects of clay as a mycotoxin binder on the health status and performance of Oreochromis niloticus in comparing with a control group revealed that the survival rate in control group was 81% after the end of the culture season. The results also revealed that the survival rate in group 2 which received clay treated feed was 86%. The results of regular parasitological examination revealed the identification of trichodina as external protozoa in Oreochromis niloticus from both ponds but without manifestation of disease signs. The results of bacteriological examination revealed the isolation and identification of Pseudomonas flouresence from some moribund Oreochromis niloticus. Higher performance parameters were recorded in group 2 that received feeds treated with clay which reflected in the total production which reaches 1646.47 kg while in the control pond, the total production was1308.36 kg.

• 한국어병학회지
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• 제2권2호
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• pp.83-90
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• 1989

Edwardsiella tarda, the causative organism of Edwardsiellosis, was isolated from the water and the eel, Anguilla japonica of the recirculating eel culture ponds in 1988. E. tarda was always isolated from the water of eel culture ponds in the number of log 2.30~log 4.78 CFU/$m{\ell}$ without distinguishable seasonal characteristics. The counts of isolated E. tarda were changed with the health condition of the eel, i. e., a number of E. tarda were isolated from all checked organs, intestine contents, liver, spleen and kidney of the diseased eel, however, it was hardly isolated from spleen and kidney of the healthy eel. The isolates were classified according to o-agglutinating test into three serotypes (I, II, III). There were no distinct differences in the composition of the serotypes between intestine contents of eel and pond water samples(I, 52.4~53.3% ; II, 20.0~23.8% ; III, 4.8~6.7%). Serotype I was ascendant in the spleen(66.7%) and the kidney(73.7%) samples. By experimental challenge, most of serotype I proved highly virulent to eel in comparison with the other serotypes tested.

• 한국어병학회지
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• 제23권2호
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• pp.165-176
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• 2010

In May 2007, mass mortality of Israeli carp, Cyprinus carpio L., was occured on a pond farm located in Jeollabukdo Province, Korea. The mortality rates reached up to 2% of the total fish in the farm per day. Typical clinical signs were abdominal distension, reddish foci on the skin, enteritis, liver congestion and enlarged spleen and kidney. On the basis of biochemical characteristics and 16S rDNA sequence, the causative bacteria isolated from affected carp were identified as Aeromonas veronii. Histologically, degeneration of hepatocytes and congestion in sinusoids were observed in the liver. Spleen showed hemorrhage and the destruction of the sheathed tissues. In kidney, necrotized renal tubules and glomerular destructions were observed. Intestinal tissues revealed necrotized and severe hemorrhage. Mass hemorrhage was observed in muscles. This is the first report that A. veronii caused mortality in cultured Israeli carp in Korea.

• 한국발생생물학회지:발생과생식
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• 제12권2호
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• pp.151-158
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• 2008

The variability within and between Korean pond-smelt (Hypomesus nipponensis; KPS) and Canadian capelin (Mallotus villosus; CCP) were studied in order to clarify the genetic distances and differences. The dendrogram obtained by the seven primers indicates cluster 1 (KOREAN 01$\sim$KOREAN 11) and cluster 2 (CANADIAN 12$\sim$CANADIAN 22). The longest genetic distance displaying significant molecular differences was found to exist between individuals in the two geographic species of Osmeridae, between individuals' no. 10 of Korean and no. 18 of Canadian (0.686). 121 unique shared loci to each species, with an average of 17.3 per primer, were observed in the KPS species, and 264 loci, with an average of 37.7 per primer, were observed in the CCP species. 77 shared loci by the two species, with an average of 11.0 per primer, were observed in the two fish species. RAPD analysis showed that the KPS species was more genetically diverse than the CCP species. KPS species may have high levels of genomic DNA variability owing to the introduction of the wild individuals from the other sites to sampling sites although it may be the geographically diverse distribution of this species. As stated above, the existence of species discrimination and genetic variability between the KPS and the CCP species was identified by RAPD analysis.

• 생태와환경
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• 제39권4호통권118호
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• pp.508-515
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• 2006

본 연구는 식물플랑크톤과 입자성 부유물질에 의해 수질문제를 야기하는 연못의 수질개선과 생태계의 기능 향상을 위해 2004년 7월부터 12월까지 수행되었다. 국내에서 대다수 연못의 관리는 자정작용과 물질순환의 생태학적 개념을 고려하지 않고 있었다. 다른 요인보다도 분수, 폭포 및 어류생물 사육에 의존되었고, 이러한 요인의 유무에 따라 수질 차이가 매우 큰 것으로 파악되었다. 연못 생태계 유지의 지속 가능성은 수질이 최우선으로 고려되는 기반이 제공되어야 한다. 물의 유입량과 유출량의 적절성과 함께 각 요소간 비율의 평형 조절이 무엇보다도 중요하다. 지속 가능성은 하나의 계에서 수평 또는 수직적 균형을 이룰 때 실현될 수 있기 때문에 이에 대한 연구 결과가 반드시 필요하다. 본 연구 결과에서 연못의 구조와 기능적 문제점이 도출된 데 대해 이러한 지속가능성을 유지하는데 가치 있는 유용성을 제공하게 되었다.

• 한국양식학회지
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• 제15권1호
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• pp.49-60
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• 2002

Research on practices for improving water quality in channel catfish Ictalurus punctatus ponds was conducted at the Auburn University Fisheries Research Station, Auburn, Alabama, in 1998 and 1999. The objective of this two-year study was to determine better management practices to enhance water quality and improve production efficiency. In the first year, oxidation of bottom soil by drying, tilling, and applying sodium nitrate was performed (dry-till and dry-till with sodium nitrate treatments). The second year, based on the results obtained during the first year, precipitation of phosphorus (P) from water by applying gypsum was compared to the dry-till treatment (dry-till and dry-till with gypsum treatments). Control ponds were not subjected to bottom drying, tilling, sodium nitrate, or gypsum treatment. Channel catfish fingerings were stocked at 15,000/ha. In the first year, water in ponds from dry-till and dry-till with sodium nitrate treatments had lower concentrations (P < 0.01) of soluble reactive P, nitrate ($NO_{3} ^{-}) and nitrite ($NO_{2} ^{-}) nitrogen (N), total ammonia ($NH_3$) nitrogen, total suspended solids and turbidity, and higher values of pH, Secchi disk visibility, total alkalinity, total hardness, and calcium ($Ca^{2+}) hardness than water in control ponds. Ponds of the dry-till treatment also had lower concentrations (P < 0.01) of total P and total N than control ponds. Total fish production and survival rate did not differ among the treatments (P > 0.05). The findings suggested that drying and tiling pond bosoms between crops could achieve water quality improvement. Applying sodium nitrate to dry, tilled pond bosoms did not provide water quality improvement. In the second year, the treatment with the best results from the first year, dry-till, was compared with a dry-till with gypsum treatment. Enough gypsum was applied to give a total hardness of about 200 mg/L, and gypsum was reapplied as needed to maintain the hardness. Compared to the control, dry-till and dry-till with gypsum treatments had lower concentrations (P < 0.01) of total and soluble reactive P, total N, and total $NH_3$-N, and higher concentrations (P < 0.01) of dissolved oxygen. Ponds of the duty-till with gypsum treatment also had lower concentrations (P < 0.01) of chlorophyll $\alpha$, chemical oxygen demand, and total alkalinity than the control. Total fish production and survival rate did not differ (P > 0.05) among the treatments. These findings suggest that drying and tilling pond bosoms between crops and treating low hardness waters with gypsum could achieve water Quality improvement.