• Fisheries and Aquatic Sciences
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• v.11 no.1
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• pp.15-22
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• 2008

Excessive growth of phytoplankton is a common and severe problem in intensively farmed pangasiid catfish (Pangasius hypophthalmus) culture ponds. It can lead to cyanobacterial blooms, reduced fish growth, bad-tasting fish flesh, and lower market demand. To investigate how to manage undesirable phytoplankton growth, we evaluated three stocking strategies in nine rural fishponds (0.020-0.022 ha) owned by various farmers: a pangasiid catfish mono culture (treatment 1, $T_1$), and pangasiid catfish-silver carp (Hypophthalmichthys molitrix) polycultures at two stocking ratios of 1:1 (treatment 2, $T_2$) and 2:1 (treatment 3, $T_3$). The total density of all ponds was approximately 30,000 fishes/ha. Monoculture ($T_1$) resulted in significantly higher (p < 0.05) nutrient levels (nitrate and phosphate) in ponds than did polyculture ($T_2$ and $T_3$). Nutrient loads increased with culture time, resulting in increased growth of phytoplankton, including Cyanophyceae (9 genera), Chlorophyceae (15 genera), Bacillariophyceae (8 genera), and Euglenophyceae (3 genera). The introduction of silver carp as a co-species helped to regulate phytoplankton growth and to improve the water quality of pangasiid catfish culture ponds.

• Korean Journal of Veterinary Service
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• v.20 no.3
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• pp.307-312
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• 1997

To investigate the species and infection rate of Tripartiella sp in three species of freshwater fish, carp(Cyprinus carpio), goldfish(Crassius auratus) and Korean catfish(Parasilurus asotus), fish cultured in the fish farms next to Yosu and in the western area of Chunbuk province in Korea was examined from April to June, 1996. The infection rate was evaluated after observing the gill and mucous from 130 fish under the microscope. The species of Tripartiella was identified on the basis of the shape and number of denticle according to methods of Bychowsky(1985) after staining the parasites with 2% methyene blue solution. All the detected-parasite was classified as Tripartiella differed from Trichodina reported previously in our country. T carassii, T californica, T rhombi from Goldfish, T rhombi from common carp, T californica from Israeli carp and T bychowsky from Korean catfish were observed. In the fish from the fish farms in the western area of Chunbuk province, the infection rate of Tripartiella sp was ranged from 6.7% to 100%, but in neither carp nor goldfish from the farms next to Yosu the parasite detected.

• Journal of Aquaculture
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• v.9 no.4
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• pp.363-375
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• 1996

The effects of the yeast, Phaffia rhodozyme in the diet on growth, body composition, muscle elasticity and pigmentation of Israeli strain of common carp, colored carp and Nile tilapia were investigated. Ten percent of the yeast was added to semi purified diet as an experimental feed 1. Ten percent of brewers yeast in the semi purified diet (experimental feed 2) was tested for comparing the growth performance between two semi purified diets. A commercial diet was also used for the check of growth rate of the semi purified diets. All experimental fish were fed for 10 weeks. The weight gains among the experimental fish were not significantly different (P>0.05). There were not significantly different in body composition, muscle elasticity among the the fishes fed three experimental diets. There were significant differences (P<0.05) of pigment deposition in the muscle of Israeli strain of common can and on the skin of colored carp between treated and non treated group. But there were no differences of pigment deposition in flesh and skin of tilapia among the three diets.

• Journal of Aquaculture
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• v.9 no.2
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• pp.151-157
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• 1996

In order to study the effects of dietary E. compresa on the growth and blood properties in young Israeli strain of common carp (mean. 8 g BW.). Fish were fed the commercial diet (control) and three experimental diets, $1\%,\;5\%\;and\;10\%$ of E. compressa powder were added to the control diet. After four months of feeding trial fish were bled by cardiac puncture and some hematological parameters were analyzed as physiological indices. 1) Following supplementation, positive responses in plasma albumin and glucose levels, and decreased body weight gain, feed efficiency and hematocrit. 2) Condition factor (fatness) in creased up to $50\%$, but decreased with $10\%$ supplementation. 3) Hb, GOT and GPT did not show any remarkable difference among all diet groups.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.15 no.4
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• pp.303-311
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• 1982

Sensory evaluations of synthetic extracts prepared on the analytical data in the previous papers (Yang and Lee, 1979, 1930-a, 1980-b, 1982) were undertaken to determine the origin of the taste of wild common carp, Cyprinus carpio, and Korean snakehead: Channa argus. Taste panel assessments of synthetic extracts prepared with each extractive component omitted were carried out by a triangle difference test, and changes in taste profile were assessed. The synthetic extracts, prepared with about 40 pure chemicals based on the analytical data from the species satisfactorily revealed the natural taste of the original extracts except slight difference in meaty taste and mildness. From the results of omission test the major components which contribute to produce the taste of the species were assessed as follows: glycine, glutamic acid, arginine, lysine, threonine, alanine, IMP, inosine, hypoxanthine, glucose, succinic acid, $Na^{+},\;Cl^{-}\;and\;PO_{4}^{3-}$ in common carp: glycine, alanine, glutamic acid, IMP, Na+ and $PO_{4}^{3-}$ in Korean snakehead.

• Ecology and Resilient Infrastructure
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• v.9 no.2
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• pp.113-123
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• 2022

The blood and physiological changes of common carp (Cyprinus carpio) and crucian carp (Carassius auratus) were analyzed when the water temperature was rapidly increased from 20℃ (control) to 26 and 32℃. The water temperature reached 26℃ and 32℃ within 6 hours from the water temperature of 20℃, and the control was maintained at 20℃ for the duration of the experiment. From each experimental group, blood was collected every 3, 12, 24 and 48 hours after the water temperature rise, and the red blood cell count, hemoglobin, hematocrit, Na⁺, K⁺, Cl^-, cortisol, glucose, aspartate amino transferase (AST) and alanine amino transferase (ALT) contents were analyzed. In the case of the crucian carp experimental group where the water temperature was raised to 32℃, the concentrations of plasma cortisol, glucose, AST and ALT increased 3 hours after the water temperature rise, and the concentrations did not decrease until 48 hours (P<0.05). Plasma cortisol, glucose, AST, and ALT in both C. carpio and C. auratus in the control group and the experimental group raised to 26℃ increased at 3 hours after the water temperature rise (P<0.05), and decreased to the value before the water temperature rise at 48 hours (P<0.05). The plasma Na⁺, K⁺ and Cl^- concentrations of C. carpio and C. auratus in the experimental group where the water temperature was raised to 32℃ were higher than in the 20 and 26℃ experimental groups. The blood reaction of all experimental groups including the control group showed a common trend in both C. carpio and C. auratus increasing up to 12 hours after the water temperature rise and then decreasing at 48 hours after the water temperature rise. The results derived from this study would be useful for investigating the physiological response of fish stress in future. In addition, as fish mortality has recently occurred frequently in rivers and lakes, it is judged that it can be used as basic data.

• Journal of Aquaculture
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• v.3 no.1
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• pp.13-23
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• 1990

An experiment was conducted to determine for the optimal phosphorus supplemention to carp feed which contains $50\%$ soybean meal, with $32\%$ protein content to obtain maximum growth of the Israeli strain of common carp (Cyprinus carpio). The experimental fish were between 100 g and 1000 g in body weight. The results, obtained were as follows: the optimum amount of phosphorus added to the experimental feed was $1.6\%$ as $NaH_2PO_4{\cdot}2H_2O$ which brings up the total amount of available phosophorus to $0.504\%$ of the feed. This amount is slightly less than the amount, $0.6-0.7\%$ which was previously reported for the Japanese native strain of carp which weighted around 4.5g. Thus there seems to be some difference for the requirement of phosphorus between the sizes of carp.

• Development and Reproduction
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• v.21 no.1
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• pp.55-62
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• 2017

We used flowcytometry to ploidy verification after that investigate difference between diploid and spontaneous triploid through the truss dimension and classical dimension at crucian carp, Carassius auratus, crucian carp C. cuvieri and common carp, Cyprinus carpio collected from Hangang river, Hantangang river, Imjingang river, Geumgang river, Yeongsangang river and Nakdonggang river, Korea. There were significant differences among the three species for the truss dimensions anterior origin of dorsal fin $(2){\times}$ anterior origin of anal fin (5), $2{\times}$ anterior origin of pelvic fin (6), $2{\times}$ origin of pectoral fin (7), posterior origin of dorsal fin $(3){\times}5$, $3{\times}6$, and $3{\times}7$ (P<0.05). There were no significant differences among the three species in the truss dimensions dorsal fin length ($2{\times}9$) and eye diameter (ED)(P>0.05). On the other hand, there were no significant differences in the several classical dimensions of each species (P>0.05). Three classical dimensions, most anterior extension of the head $(1){\times}2$, $1{\times}6$ and $2{\times}$ most posterior scale in lateral line (4) did not differ between the C. auratus diploid and spontaneous triploid (P>0.05). Two classical dimensions, $1{\times}6$ and longest length between most anterior extension of the head and gill cover ($1{\times}8$) did not differ between the C. cuvieri diploid and spontaneous triploid (P>0.05). One classical dimensions, $1{\times}2$ did not differ between the common carp diploid and spontaneous triploid (P>0.05). There were significant differences in the each diploid and triploid species (P<0.05). These results suggest that the classification of each species and classification between diploid and spontaneous triploid morphometrical parameters used in this study are useful indices of morphometrical status in the each species from major river of Korea.

• Fisheries and Aquatic Sciences
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• v.23 no.6
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• pp.16.1-16.10
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• 2020

This study was conducted in Lake Hayq between January and December 2018. The objectives of this study were to determine the growth, condition, sex ratio, fecundity, length at first sexual maturity (L₅₀), and spawning seasons of common carp (Cyprinus carpio). Monthly fish samples of C. carpio were collected using gillnets of stretched mesh sizes of 4, 6, 7, 8, 10, and 13 cm and beach seines of mesh size of 6 cm. Immediately after the fish were captured, total length (TL) and total weight (TW) for each individual were measured in centimeters and grams, respectively, and their relationship was determined using power function. Length at first maturity (L₅₀) was determined for both males and females using the logistic regression model. The spawning season was determined from the frequency of mature gonads and variation of gonadosomatic index (GSI) values of both males and females. Fecundity was analyzed from 67 mature female specimens. The length and weight relationship of C. carpio was TW = 0.015TL^2.93 for females and TW = 0.018TL^2.87 for males that indicate negative allometric growth in both cases. The mean Fulton condition factor (C_F) was 1.23 ± 0.013 for females and 1.21 ± 0.011 for males. The value of C_F in both cases was > 1 that shows both sexes are in good condition. Among the total 1055 C. carpio collected from Lake Hayq, 459 (43.5%) were females and 596 (56.5%) were males. The chi-square test showed that there was a significant deviation between male and female numbers from 1:1 ratio (χ²= 22, df = 11, P > 0.05) within sampling months. The length at first sexual maturity (L₅₀) for females and males were 21.5 and 17.5 cm, respectively. Males mature at smaller sizes than females. The spawning season of C. carpio was extended from February to April, and the peak spawning season for both sexes was in April. The average absolute fecundity was 28,100 ± 17,462. C. carpio is currently the commercially important fish while Nile tilapia fishery has declined in Lake Hayq. Therefore, this baseline data on growth, condition, and reproductive biology of common carp will be essential to understand the status of the population of carp and design appropriate management systems for the fish stock of Lake Hayq, Ethiopia, and adjacent countries.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.5
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• pp.484-489
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• 2011

This study examined whether N-acetylcysteine (NAC), a glutathione precursor, could attenuate toxic effects of three fish anti-parasitic agents, trichlorfon, hydrogen peroxide ($H_2O_2$) and formalin, all of which are known to exert side effects through free radical production. Common carp Cyprinus carpio were fed with NAC (approx. 50 mg/kg/day) for 3 consecutive days prior to anti-parasite bathing for a 24 hr period. Mortality rates were examined during this 24 hr bathing period, and selected hematological and biochemical parameters were also assessed at the termination of anti-parasite exposure. The mortality rates and plasma glucose elevations caused by all three anti-parasitics were significantly reduced by NAC pretreatment. Trichlorfon, but not $H_2O_2$ or formalin, elevated plasma levels of aspartatetransaminase (AST) and alanine-transaminase (ALT), and these elevations were attenuated by NAC. There was no change in hematocrit values in any treatment. The results provide evidence for the attenuating effects of NAC against toxicity caused by anti-parasite agents that act through free radical-producing properties. The results found in this study also suggest that NAC may be administered to fish to minimize toxicity in fish parasiticide use.