Influence of stoking densities, intensive and semi-intensive rearing systems on carcass yield, nutricional quality of the fillet and organoleptic characteristics of pintado Pseudoplatystoma corruscans

Abstract

The objective of the study was to evaluate the effect of the rearing system on the carcass yield, fillet quality, as well as flavor of surubim-pintado meat raised in 3 different systems, as follows: net cage í  133 fish m^-3 (NC133), net cage í  67 fish m^-3 (NC67) and ponds í  0.75 fish m^-2 (P). The fish were fed a commercial diet for a period of 272 days. To evaluate carcass yield and proximate composition of the fillets, 24 fish per treatment were striped and processed manually. A group of 33 no-trained testers performed sensorial analysis by attributing a relative value to flavor. Data were then analyzed by block randomized experimental design, and no differences were found among treatments. Average weight was higher for P compared to other treatments; however, fillet yield and total residues were similar to NC67 treatment. Significant differences were observed among treatments for proximate composition, fish fillets from P treatment presented lower moisture and higher fat contents, while CLD treatment displayed an inverse relationship. The carcass yield and proximate composition varied with the different rearing systems and different development densities, and the best results were obtained when fish were raised in net cage in the density of 67 fish m^-3.