Dietary substitution of fish meal by meat meal: Effects on juvenile olive flounder (Paralichthys olivaceus) growth performance, feed utilization, haematology, biochemical profile and disease resistance against Streptococcus iniae

This study investigated dietary substitution effect of fish meal (FM) with meat meal (MM) on growth, feed utilization, chemical composition, and amino and lipid acid profiles of juvenile olive flounder (Paralichthys olivaceus) and challenge test against Streptococcus iniae. A total of 525 fish were distributed into 21 flow-through tanks. 650 g/kg FM was included in the control (Con) diet. 100, 200, 400, 600, 800 and 1000 g/kg of FM were substituted with MM, referred to as the MM100, MM200, MM400, MM600, MM800 and MM1000 diets, respectively. Fish were daily hand-fed to apparent satiation for 8 weeks. The highest weight gain, specific growth rate and feed consumption were obtained in fish fed the MM200 diet. Weight gain, specific growth rate, feed consumption, protein efficiency ratio, protein retention and condition factor of fish fed the MM100 and MM400 diets were not significantly (p > .05) different from those of fish fed the Con diet. Plasma chemistry and non-specific immune responses of fish were not significantly (p > .05) affected by the experimental diets. No significant (p > .9) difference in survival of fish after S. iniae infection was observed during the 8-day postobservation. In conclusion, FM up to 400 g/kg could be replaced with MM without deterioration of growth, feed consumption, feed utilization, non-specific immune responses and disease resistance of fish against S. iniae.