Rendimento de carcaça e composição centesimal de filé de peixes criados em sistema de policultivo, alimentados com ração artesanal orgânica ou comercial convencional

Abstract

Organic fish farming is an alternative production that can be very interesting for rural family farmers, even with a greater aggregation of the value of fish compared to conventional fish. The type of diet and feeding management can directly influence the body composition of the fish. In this sense, the objective of this study is to analyse the carcass yield and chemical composition of fillets of fish grown in an agroecologicalbased polyculture system, fed with a conventional extruded organic or commercial pelleted artisanal diet for 12 months in a quadripartite. The total of 168 specimens of seven different species, Jundiá (Rhamdia sp.), common carp (Cyprinus carpio), cascudo (Pterygoplichthys josemalicus), curimba (Prochilodus lineatus), silver carp (Hypophthalmichthys molitrix), big head carp (Hypophthalmichthys nobilis) and grass carp (Ctenoppharyngodon idella) collected at random at the end of cultivation, were analyzed for yield of gutted whole fish (RPIE%), the whole fish yield eviscerated without head, fins and skin (RPISC%) and fillet yield (RFILE%). Abdominal muscle yield (RMA%) and yield of edible parts (RPCOM% = RFILE + RMA), and centesimal composition of fillet (dry matter, lipid, protein and ash) were obtained only for jundiá. The experimental design was completely randomized, with 4 replicates (n = 12; 3 fish of each species / replicate). The data were statistically analyzed via Student's t test (P<0.05). The type of diet used did not significantly influence the yield of most of the different evaluated cuts. With the exception of the yield of whole eviscerated, headless, finned and carp fish, which was higher in fish fed with organic feed. Regarding the evaluated residues, treatment with organic feed resulted in a higher skin yield in the curimba and a lower hepatosomatic rate for jundiá. The different diets did not influence the centesimal composition of the fillet of any of the evaluated species. These results suggest that organic feed can be used in fish farming without causing damage to the production process.