Growth, feed conversion and mortality of cagereared tambaqui, Colossoma macropomum, fed various dietary feeding regimes and protein levels

Abstract

Artificially reproduced tambaqui, Colossoma macropomum, fingerlings (initial weight 30 g) were stocked (150/m 3) in either 0.5-m 3 or 1.0-m 3 plastic cages within a freshwater reservoir to study culture performance with various dietary feeding regimes and protein levels. Two feeding trials were conducted. In the first, three feeding regimes were tested over a 194-day feeding period: (A) variable feeding regime decreasing from 5 to 2% body weight/day, fed twice daily; (B) fixed feeding regime at a rate of 3% bw/day, fed twice daily; and (C) fixed feeding regime at a rate of 3% bw/day fed once daily. In the second experiment three dietary protein levels were tested: 30, 35, and 40%. No significant differences ( P < 0.05) were observed in mean final body weight, specific growth rate and feed conversion efficiency between the feeding regimes or dietary protein levels tested. Based on this study, it would appear that fingerling/juvenile tambaqui can be satisfactorily grown with the regimes and diets tested. Considering cost efficiency and net production, the lower protein levels should be preferred.