• Fisheries and Aquatic Sciences
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• v.6 no.4
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• pp.194-202
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• 2003

Budgets for water, nitrogen, and chemical oxygen demand (COD) were determined in two 0.012 ha earthy-bottom ponds stocked with Israeli strain common carp at an initial stocking density of $20\;fish/m^3$. Total ammonia nitrogen (TAN) concentrations increased continuously but later decreased in pond A as a consequence of high nitrification. COD concentrations increased during the experimental period due to the accumulation of feed input. Nutrient budgets showed that feed represented $94-95\%$ of nitrogen input and about 99% of organic matter input. Fish harvest accounted for $40\%$ of nitrogen and organic matter input. Seepage and water exchange removed $15-17\%$ of nitrogen input but only $1-2\%$ of organic matter. Draining of the ponds removed $20-26\%$ of input nitrogen, mostly in inorganic forms, but removed only minus organic matter. Fish and water column respiration accounted for $39\%$ of organic matter input, and benthic respiration accounted for $7-12\%$ of organic matter input. No significant change of nitrogen and organic matter in both pond bottoms were found during the three-month growth period. The unrecovered input nitrogen, about $6.3-13\%$, was lost through denitrification and ammonia volatilization. On a dry matter basis, fish growth removed $31\%$ of total feed input and left $69\%$ as metabolic wastes.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.16 no.3
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• pp.190-196
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• 1983

This experiment was carried out to compare the change of muscle protein compositions, amino acid compositions of muscle protein, and free amino acid compositions by age of the Israeli strain of common carp, Cyprinus carpio nudus. Protein compositions of the muscle were: sarcoplasmic protein $25.8-27.2\%$, myofibrillar protein $62.3-56.2\%$, residual intracellular protein $9.6-13.2\%$ and stroma $2.3-2.9\%$. In between 1 year and 3 years, there were differences as follows; myofibrillar protein in 1 year was much than 3 years, and other proteins in 3 years were much than 1 year. By SDS-polyacrylamide gel electrophoresis, sarcoplasmic protein of the samples in 1 year an 3 years were composed of 11 subunits and 10 subunits, respectively. And appeared 210,000 dalton component in 1 year but did not appeared in 3 years. Myofibrillar protein was composed of 23 subunits in both 1 year and 3 years but the differences of subunits by age were not observed. No differences were observed by age in the composition of myofibrillar protein and residual intracellular protein. Amino acid composition of muscle protein in both 1 year and 3 years were no differences to each other, but the contents of glutamic acid, aspartic acid, lysine were higher than other amino acids. The amount of total free amino acid in 1 year was much than in 3 years.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.13 no.4
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• pp.195-206
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• 1980

Fish were grown in a water recycling rearing system consisting of a filter system, of which the area is about $30\;m^2$ and the volume of filter gravels is about $15\;m^3$, 6 rearing and 2 supplementary tans about $7\;m^2$ of surface area each. The results for 180 days from April 18 to October 14,1980 are summarized as following: One rearing tank was used for main experiment stocked with an equal number, and weight of each Israeli strain and $F_1$, hybrid between this strain and Korean local strain of common carp. Gross total production was 461 kg with a net production of 395 kg, and the Israeli strain grew to about 8 times initial weight and the hybrid about 6 times. Based on an analysis of results of the above mentioned main experiment and the other miscellaneous fish grown in the remaining tanks, it was considered to be feasible to implement a commercial production in this system by improving parts of the system and adding a number of the units. A special problem seems to be an adoption of more effective aeration device when fish loading increases. A solid waste removal system was deviced by use of by-pass flow ana this system worked very efficiently in view of supply water economy. A serious problem encountered in this experiment was heavy outbreaks of the gill-fluke, Dactylogyrus sp. which was relatively easily eradicated with Dipterex or DDVP treatment in the first trials, but later on strains which were resistant to any of these chemicals appeared.