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ABSTRACT: Effects of dietary fatty acid composition on the growth of the tiger puffer Takifugu rubripes were examined. Eight experimental diets were formulated with fish meal and casein as the major ingredients, providing 45.0–48.2%
crude protein. Pollack and squid liver oils were used for the control diet while experimental diets contained three levels
of EPA-DHA concentrated (C-HUFA) oils, soybean oil, linseed oil, and combinations of them, providing 0.5–5.5% n-3 HUFA and
5.0–11.1% crude lipid. Triplicate groups of fish with a mean body weight of 18.7g per dietary treatment were fed the diets
twice daily to apparent satiation, 6days per week for 8weeks. The final body weight and weight gain of the fish fed the
soybean oil diet without C-HUFA oils were significantly lower than those fed the control diet. Both parameters were not statistically
different among the other dietary groups, although the values obtained for the linseed oil diet without C-HUFA oils were lower.
Similar trends were seen for SGR and feed efficiency. However, significantly lower PER values compared to the control were
observed for the lower C-HUFA and the vegetable oil without C-HUFA oil groups. These results indicate that tiger puffer can
be produced successfully with diets containing more than 1.5% n-3 HUFA.
KeywordsTiger puffer–Dietary fatty acid–HUFA–Growth–Body composition
Fisheries Science 04/2012; 77(5):829-837. · 0.94 Impact Factor
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ABSTRACT: The acute toxicities of copper were examined for Japanese flounder, Paralichthys olivaceus, and red sea bream, Pagrus major, in terms of fish size and water temperature. Artificial seawater of low pH of 5.4–6.7 was used as testing water to keep dissolved copper concentration at 0.04–41 mg Cu/L. Japanese flounder of 0.3–17 g and red sea bream of 0.5–13 g were exposed to different concentrations of copper for 96 h at 20 C under semistatic condition. Median-lethal concentration for 96 h of Japanese flounder and red sea bream were 8.7–12.2 and 2.0–5.2 mg Cu/L, respectively. No significant relationships were observed between median-lethal concentrations for 96 h and fish size for Japanese flounder, while the value decreased significantly with increasing fish size for red sea bream. Effect of water temperature on the acute toxicity was examined for Japanese flounder of 0.3 and 0.4 g at 10, 15, 20, and 25 C and red sea bream of 0.5 and 1.0 g at 12, 15, 20, and 25 C. Ninety-six-hour median-lethal concentrations for Japanese flounder and red sea bream were 5.1–11.2 and 1.0–5.3 mg Cu/L, respectively. No significant relationships were observed between median-lethal concentrations for 96 h and water temperature for both fish species.
Journal of the World Aquaculture Society 12/2008; 39(6):766 - 773. · 0.71 Impact Factor
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ABSTRACT: Two feeding experiments were conducted to elucidate growth performance of tiger puffer in a 10 m3 water volume closed system. In experiment 1, 1000 fish of 3.5 g average body weight were fed tiger puffer commercial feed twice daily to apparent satiation, 6 days a week for 224 days. Sand-filtered sea water was used and no water was exchanged during the rearing period. Immediately after cutting of lower teeth at day 112, daily feed consumption decreased greatly and 60 fish died in few days. Feeding rates recovered and then decreased gradually as nitrate levels increased from 600–1048 mg N/L. Fish grew to 343 g with 91% survival rate and 87% feed efficiency. Rearing conditions of experiment 2 were similar to experiment 1, except that culture water was exchanged to maintain the nitrate level less than 600 mg N/L during the 224-day experiment. Mortality and reduction of feed consumption occurred immediately after teeth cutting as was observed in experiment 1. Significant reduction of feed intake was not found during other rearing periods. Fish of 3 g grew to 303 g with 91% survival rate and 72% feed efficiency.
Fisheries Science 09/2006; 72(5):1042 - 1047. · 0.94 Impact Factor
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ABSTRACT: Larval false clown anemonefish of about 12 h after hatching were fed newly-hatched brine shrimp nauplii in natural (control) and copper-added seawater (40–640 µg–Cu/L) at 26.5 ± 0.5°C for 14 days. Survival rate of the fish increased with increasing copper concentrations up to 160 µg–Cu/L. The rates at 80 and 160 µg–Cu/L were 65 and 80%, respectively, and were significantly higher than that of the control (30%). A positive effect of copper addition on the survival rate was also observed in the other rearing experiment with the fish from seven different spawning chances. Growth rate of the survival fish was not affected by copper concentrations. The copper concentration of the survived fish increased with increasing copper concentrations in the rearing water.
Fisheries Science 08/2005; 71(4):884 - 888. · 0.94 Impact Factor
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ABSTRACT: Rearing experiments were carried out to clarify the effects of sandy substrate and light irradiation on hypermelanosis of the blind side (the staining type of ambicoloration) in cultured Japanese flounder. Fish were reared in three experimental conditions: (1) no sandy substrate into which fish could bury themselves and with upward light irradiating their blind sides, (2) no sandy substrate and no upward light, and (3) sandy substrate (transparent glass sand) with upward light irradiation. Pigmented areas on the blind side were measured by an image analyzing system. Flounder from the third condition (sandy substrate with light irradiation) showed the lowest pigmentation on the blind side. In contrast, fish from the second condition (no sandy substrate and no light irradiation), showed the highest pigmentation coverage. These results indicate that sandy substrate on the bottom in culture tanks is more important than light irradiation as a factor affecting hypermelanosis of the blind side in cultured Japanese flounder.
Environmental Biology of Fishes 01/1998; 52(1):291-297. · 0.91 Impact Factor
