Assessment of the effect of mixed replacement of animal and plant protein-based mixes on fish growth indices, body composition and somatic index of Huso Huso

A mixture of vegetable and animal proteins (corn gluten, wheat gluten, processed soy flour, poultry by product, meat and bone meal and blood meal) that are chemically similar (protein, fat, carbohydrate and dry matter) and similar to amino acid profiles compred fish meal were replaced fish meal in diets with identical levels of protein (44%), energy (18 MJ /kg) at levels of  20, 40, 60 and 80% (MPP20, MPP40, MPP60 and MPP80). Juvenile Huso huso with average weight of 167± 6.5 g were fed diets to saturation and their growth indices, carcass composition, hepatosomic and visceral indexes were studied. The final weight, final length, condition factor, weight gain, body weight precent, specific growth rate, daily growth, feed conversion ratio and protein efficiency ratio were not affectrd with diets (p>0.05). Carcass protein of fish fed MPP60 and MPP80 were significantly decreased compared to fish fed diet based on fish meal, while fish carcass fat increased significantly in these fish (p<0.05). There was no significant difference in hepatosomatic and visceral index in fish fed diets based on fish meal (p>0.05). The results of this experiment showed that it is possible to replace 80% of a mixture of animal and vegetable proteins with fish meal without adversely affecting growth indices, hepatosomal and visceral index  of  Huso huso in growth rate period.