Vegetable oils in diets for hybrid tambacu (male “Piaractus mesopotamicus” x female “Colossoma macropomum”)

Abstract

The objective of this work was to evaluate the inclusion of vegetable oils in diets for tambacu. 315 specimens (1.93 ± 0.16g) were used in 21 happas with dimensions of 0.60 x 0.30 x 0.60m. The design was completely randomized in a factorial 2 x 4, two sources of oils (soybean and palm oil), four levels (0; 3; 5 and 7%) and three replicates with 15 fish per experimental plot. The oil sources were added to a commercial extruded feed containing 36% crude protein, 4505Kcal/Kg crude energy and 7% ether extract. The feeding was carried out ad libitum, four times daily for 60 days. For final weight, daily weight gain, specific growth and survival, rate, no significant differences were observed for fish fed diets with palm oil or soybean, regardless of the levels. The oil inclusion levels influenced with linear increasing, the daily feed intake and feed conversion and protein variables of the tambacus. There were no significant differences for fish fed diets with palm oil or soybean, regardless of the levels, for dry matter, crude protein and ash in the carcass. A significant result of oil inclusion level was observed on the variables of carcass fat and protein deposition rate, with a linear increase. The inclusion of soybean oil and palm oil does not improve the performance of juvenile tambacu, however there is an increase in the efficiency of protein utilization.