Feeding ratio affects growth, body composition, and blood chemistry of mandarin fish (Siniperca scherzeri) in recirculating aquaculture system

The effects of various feeding ratios on the growth, body composition, and blood chemistry juvenile mandarin fish Siniperca scherzeri (initial weight 9.6 g) were examined in recirculating freshwater system equipped with 21, 300 L tanks at 20 per tank. triplicate groups seven treatments prepared: 100% (control), 95%, 90%, 85%, 80%, 75%, 70% satiation. feed amount control group was determined by supplying apparent satiation then amounts other six based group. Fish hand-fed test diet (55.4% crude protein) for 10 weeks. Weight gain (WG) specific growth rate fed to not significantly (p > 0.05) different from those ≥ 80% but higher than 75% Feed efficiency, protein efficiency ratio, retention 95% 90% <0.05) lower ≤ 85% Condition factor, hepatosomatic index, coefficient variation affected ratio. Whole composition contents hematocrit, glutamic oxaloacetic transaminase, pyruvic glucose, total protein, high-density lipoprotein cholesterol serum ratio; however, content tended decrease as ratio decreased. Using broken-line analysis WG, it suggested that optimum fish, ranging 9.0 g 37.0 g, appeared be 87.7% without inhibition.