Effect of flour fish hydrolyzate in the growing of rainbow trout (Oncorhynchus mykiss)

Objective. To assess the effect of the inclusion of viscera hydrolyzate meal in diets for trout fry, "Kamloop" variety, in terms of weight, length and biomass gains, apparent feed conversion, and survival. Materials and methods. This essay was developed at the Guirapungo - Corponarino Environmental and Fish Farming Center, in eight concrete pools, subdivided each pool, into three compartments of equal dimensions. An Unrestricted Random Design (URD) was used, made up of 1680 trout fry, with an average stocking weight of 1.24 +/- 0.024 g, distributed in four treatments, six replications per treatment, for a total of 24 units experimental, with 70 fish per experimental unit and 420 fish per treatment. Results. Treatment 4, (diet with 20% viscera hydrolyzed) recorded the greatest weight, length and biomass gains, the best feed conversion and average survival. In contrast, the T1 treatment (commercial feed) reported the least adequate productive variables. Conclusions. The incorporation of fish viscera hydrolysate, as a protein source in balanced diets of rainbow trout, improve the zootechnical variables of fish production, due to the biological value of the diets that the hydrolyzate contains.