Processamento da ração no desempenho de juvenis de jundiá (rhamdia voulezi) cultivados em tanques-rede

Abstract

The aim of this study was to evaluate the zootechnical performance and chemical composition of Rhandia voulezi juveniles fed with mash, pelleted and extruded diets and reared in cages. One hundred and fifty fish were distributed into 15 net cages (0.20 m³), arranged in 5m³ net cages, in the hydroelectric plant of Governador José Richa, in Iguaçu River (Paraná-Brazil). The fish were fed five times a day, with mash, pelleted and extruded diets, containing 30% of protein and 3,250 Kcal/kg of digestible energy/kg. At the end of 60 days, significant differences (p<0.05) were observed on fish performance. The fish that were fed with pelleted diet presented higher average of final weight (44.08g), final length (16.51cm) and weight gain (36.65g). The different processes did not influence fish survival. The averages of protein and mineral matter of carcass chemical composition did not differ statistically (p<0.05), while the values of humidity and lipids presented differences among treatments. The highest average of lipids (8.59%) was observed in pelleted diet. The mash diet provided fish with lower lipids (5.45%) and higher humidity (75.98%) rates. A pelleted diet is more suitable for juvenile catfish R. voulezi reared in cages.