Effect of dietary inulin as prebiotic on growth performance and survival of juvenile Rainbow trout (Oncorhynchus mykiss)

An 8-week feeding experiment was conducted to investigate the effects dietary prebiotic inulin on growth performance and survival of juvenile Rainbow trout (Oncorhynchus mykiss). Three replicate groups of fish (initially averaging weight 15.58±0.6 g) were fed diets containing prebiotic inulin (Raftifeed® IPS) levels 1% , 2% and 3%. The basal diet was contained 3% cellulose. Fish were fed to apparent satiation and growth performance monitored. Growth indicies such as; final weight gain, specific growth rate (SGR), thermal growth coefficient (TGC) and net production of fish fed the basal diet were significantly higher than those fed the diets containing prebiotic inulin. However, there were no significant differences in food converstion ratio (FCR), feed efficiency (FE), protein efficiency ratio (PER) and condition factor (CF) among fish fed the experimental diets. No significant difference was observed in survival rate at the end of trial. The experiment indicated that the prebiotic inulin didn’t influence the increase of the growth performance and survival rate in rainbow trout juvenile.