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This study evaluated the potential to replace dietary fish meal with gamma‐ray (γ)‐irradiated feather meal and non γ‐irradiated feather meal for golden pompano Trachinotus ovatus. The basal diet (R) contained 250 g/kg fish meal, and 20% and 40% of the fish meal were replaced by either γ‐irradiated feather meal (IF20 and IF40) or non γ‐irradiated feather meal (F20 and F40). Fish were fed the test diets in inshore net pens for eight weeks. The weight gain of fish fed diet R did not significantly differ from those fed diet IF20, but was higher than those fed diets F20, F40 and IF40. No significant differences were found in feed intake, feed conversion ratio, retention efficiencies of carbon and nitrogen, condition factor, hepatosomatic index and wastes of carbon and nitrogen between fish fed diet R and diets F20, F40, IF20 and IF40. This study reveals that γ‐irradiated feather meal could replace more fish meal in golden pompano diet than that replaced by non γ‐irradiated feather meal, and dietary fish meal content could be reduced to 200 g/kg by inclusion of 43 g/kg γ‐irradiated feather meal as a fish meal substitute. Replacing dietary fish meal with either γ‐irradiated feather meal or non γ‐irradiated feather meal could shift carbon–nitrogen–phosphorus atomic stoichiometry in the coastal waters for golden pompano aquaculture. [ABSTRACT FROM AUTHOR]

An eight‐week feeding trial was conducted to evaluate the feed intake, growth, feed utilization, body composition and waste output of juvenile hybrid bream at different feeding frequencies (0.5, 1, 2, 3 or 4 meals/day). Fish (initial body weight of 10.6 ± 0.8 g) were fed to satiation at each feeding. The test diet contained 336 g/kg crude protein and 79 g/kg crude lipid. The weight gain significantly increased with increase in feeding frequency from 0.5 to 3 meals/day (p < 0.05) and afterwards did not change with feeding frequency from 3 to 4 meals/day (p > 0.05). The feed intake increased with increase in feeding frequency (p < 0.05). Fish fed at 3 meals/day exhibited the lowest feed conversion ratio and waste output of nitrogen and phosphorus, however, the highest nitrogen retention efficiency (p < 0.05). No significant differences were found in the phosphorus retention efficiency, the body composition of crude protein, ash and phosphorus among all the feeding frequencies (p > 0.05). The body lipid content increased, whereas the content of moisture decreased, with the increase in feeding frequency (p < 0.05). The present study reveals that the optimum feeding frequency is 3 meals/day for hybrid bream. [ABSTRACT FROM AUTHOR]