The aims of this research were to evaluate the zootechnical performance and dietary cost for the marine shrimp
(Litopenaeus vannamei) cultured in a superintensive biofloc system and a conventional semi-intensive system
using diets containing different protein levels. Four different diets, with crude protein (CP) contents of 24.3,
30.3, 32.9 and 36.7%were produced. In the laboratory, experimental culture in the biofloc systemwas performed
in twelve experimental units at a density of 250 shrimpm−3, the four treatments were performed in triplicate. The
semi-intensive culture system was applied at the commercial farm in eleven ponds containing 15.5 shrimp m−2.
After 49 days, the zootechnical performance of the shrimp was rated, and the cost per kilogram of shrimp was
produced by both culture systems. In the semi-intensive system, the shrimp fed with a diet containing 32.9%
CP showed a higher final weight and weight gain and a lower dietary cost. In the biofloc culture, a higher final
weight, weight gain, growth rate and productivity were observed in shrimp fed diets containing 30.3, 32.9 and
36.7% CP compared with those fed a diet containing 24.3% CP. The lowest dietary cost of shrimp farming in the
biofloc system was registered in the shrimp fed the 30.3% CP diet, whereas, in the semi-intensive system, the
highest final weight, highest weight gain and lowest cost were observed in shrimp fed the 32.9% CP diet