Effect of supplimentation with algae (Sargassum ilicifolium) on growth, survival and body composition of rainbow trout Oncorhynchus mykiss

The effects of substituting diet protein sources with different levels of Sargassum ilicifolium on growth, survival and body composition of rainbow trout Oncorhynchus mykiss were investigated over the course of 60 days experiment. A total of 360 juveniles (75±2.8 g) were randomly allotted to four treatment groups including (control: with 100% basal diet (BD); T1: 5% Sargassum meal (SM) + 95% BD; T2: 7.5 % (SM) + 92.5 % BD and T3: 10 % (SM) + 90% BD. Each treatment group was divided into three replicates of 30 fish per replicate. At the end of the experiment course, our results showed that 5% and 7.5 % of basal diet could be replaced with Sargassum meal by different significant on average weight and total length , feed conversion ratio (FCR), specific growth rate (SGR), weight gain percent (WG), condition factor (CF) and survival rate (SR). There were significant differences between Calorie carcass of T2 and control with T1 and T3 (P<0.05). The highest values of carcass protein content were observed in T1 (P<0.05). There were significant differences between lipid content of T2 and control with T1 and T3 (P<0.05). The highest values of carcass ash content were observed in T1, (P<0.05) while there were not significant differences between other treatments (P>0.05).All kind of amino acids were higher in T2.

Keywords:

Protein sources , Sargassum ilicifolium , growth , survival , body composition , rainbow trout