Possibilities of using sprat (Sprattus sprattus Linnaeus, 1758) fish meal in rations of rainbow trout (Oncorhynchus mykiss)

In this study, the effects of diets which containing sprat and anchovy meal on growth, feed conversion, amino acid composition, fatty acid amounts and body composition of rainbow trout (Oncorhynchus mykiss) were investigated.Initial average weight of fishes used in the experiment are determined as130,25 ±0,03 g for diet added anchovy meal (A) and 130,08 ±0,03 g for diet added sprat meal (S). In the experiment two different diets which contain 46.53% protein, 20.89% oil for group A and 46.47% protein, 20.85% oil for group S have been prepared and, fishes were fed with these diets throughout 60 days.At the end of the research, weight gain (WG) was determined as 146.25 ± 6.00 g and 145.45 ± 3.53 g in the group A and group S, respectively. Specific growth rate (SGR) was identified as 1,19 ± 0,03 % and 1,19 ± 0,01 % for groups which were fed diet added anchovy meal and diet added sprat meal, respectively. Feed conversion ratios (FCR) were determined as 0.94 ± 0.03 in the group A and 0.90 ± 0.07 in group S. Differences between FCR values are not significant statistically ( p> 0.05).Survival rate (SR), protein consumption (PC), protein efficiency ratio (PER), hepatosomatic index (HSI) and vicerosomatic index (VSI) values are numerically different for two groups but differences between groups were not significant statistically (p>0.05). Both of experimental groups have higher protein (94.31 % - 94.39 %) and fat (% 96.23-97.16%) digestibility rate and differences between groups were not significant statistically (p> 0.05).In this study have been determined that using totally sprat meal instead of anchovy meal in the rainbow trout diet has not any negative effect on growth and feed conversion. When sprat meal or anchovy meal used in the diet, growth performance values was determined the same. Consequently, it is determined that sprat meal with rate of 100% can be used instead of anchovy meal in the rainbow trout diet .