The aim of this study was to determine the effect of a vegetable diet compared to a diet containing fishmeal at the commercial level (6%) on body growth, proximal composition of fillets and hematological parameters of juvenil gamitana (Colossoma macropomum). The experiment followed a completely randomized design with two treatments, an exclusively vegetable diet and a diet with low fishmeal content (6%), and three 200 m3 dug earthen ponds as experimental units per treatment. A total of 1200 fish (172.9 g; 19.4 cm) distributed in the six ponds (1 fish/m3) were used. Feeding was done twice a day (08:00 and 16:00) at a daily feeding rate of 2% for 60 days. The water quality parameters were monitored daily and showed constant values and within the comfort range of the species. The exclusively vegetable diet had a similar effect as the fishmeal diet on body growth [final weight 258.9 g, weigh...