Effect of fermented Daphnia meal with Bacillus probiotic in-feed of Rainbow trout (Oncorhynchus mykiss) larvae on growth performance and carcass composition

In a completely randomized experiment, the effect of Daphnia magna meal on growth performance and carcass composition of rainbow trout (Oncorhynchus mykiss) larvae (body weight 0.538±0.197 g) was evaluated for a period of 60 days. Five diets with the same protein content (crude protein 52.70%) were prepared, including two diets containing fermented daphnia meal T1 (20%), T2 (30%), two diets containing raw meal T3 (20%) and T4 (30%), and a basal diet without daphnia meal as the control. The bacterial species used for fermenting included five commercial probiotic species. Fermented daphnia meal brought about significantly higher growth and the lowest feed conversion ratios, viz. T1 (1.27 ± 0.35) and T2 (1.31 ± 0.46), in comparison with T3 (1.38 ± 0.37), T4 (1.41 ± 0.42) and the control (1.84 ± 0.69) (p