Seasonal variation of nutrients and energy in tambaqui's (Colossoma Macropomum Cuvier, 1818) natural food.

The aim of this study was to evaluate the importance of fruits and seeds as food items in the natural diet of the tambaqui (Colossoma macropomum). During one year, tambaqui's stomach contents were collected, and their nutritional and energetic values were determined. During the flooding period, and while the river water was rising, which coincided with a high availability of fruits and seeds, the protein content of food was low (11%-15% of dry matter basis), whereas in the dry season, when tambaqui fed mainly zooplankton, there was a high protein content (45%-57% of dry matter basis). Lipid, carbohydrate, crude fiber, ash and gross energy contents of the diet varied depending on the river water level and the food items ingested.