The effect of the dietary substitution of fishmeal with tuna by-product meal on growth, body composition, plasma chemistry and amino acid profiles of juvenile Korean rockfish (Sebastes schlegeli)

Abstract

The effect of the substitution of fishmeal with tuna by-product meal (TBM) in the diet of Korean rockfish on growth, body composition, plasma chemistry and amino acid profiles was determined. Nine experimental diets were prepared. The control (Con) diet consisted of 550 g kg−1 fishmeal. The 10, 20, 30, 40, 60, 80 and 100 % fishmeal diets were substituted with tuna by-product meal (TBM), referred to as the TBM10, TBM20, TBM30, TBM40, TBM60, TBM80 and TBM100 diets, respectively. Finally, the fishmeal and soybean meal was completely replaced with TBM in the diet TBM100-S. There was no significant difference in weight gain and SGR of the fish that were fed the TBM40 and Con diets. The feed conversion ratio (FCR) of the fish that were fed the Con, TBM10, TBM20 and TBM30 diets was lower than that of the fish that were fed all of the other diets. The protein efficiency ratio (PER) of fish that were fed the TBM10, TBM20 and TBM300 diets was higher than that of fish that were fed the TBM40, TBM60, TBM80, TBM100 and TBM100-S diets. It can be concluded that the substitution of fishmeal with up to 40 and 30 % TBM in the diet of juvenile Korean rockfish could be made without exerting a detrimental effect on their growth (SGR) and feed utilization (FCR and PER), respectively.