| Popis: |
The present study evaluated the production of Litopenaeus vannamei in a high density biofloc-dominated system using two commercial feeds; a less expensive feed (US$0.99 kg−1) formulated for semi-intensive systems and the more expensive (US$1.75 kg−1) which was designed for hyper-intensive systems. A 67-days study was conducted in six 40 m3 lined with Ethylene Propylene Diene Monomer membrane raceways (RWs) filled with mixture of seawater (22 m3), and biofloc-rich water (18 m3). Each RW was stocked (500 shrimp m−3) using juveniles (2.66 g) produced from Taura-Resistant and Fast-Growth breeding lines. The study was composed of two feed treatments with three replicates each; the cheaper feed (SI-35) contained 35% crude protein (CP), 7% lipid and 4% fiber while the more expensive one (HI-35) had the same levels of CP and lipid but only 2% fiber. The SI-35 treatment required more solids removal, oxygen, and bicarbonate supplementation than the HI-35 treatment. Weekly growth, total biomass, yield were significantly lower in the SI-35 treatment, whereas feed conversion ratio was higher. The economic analysis indicates that both feeds would be commercially viable, nevertheless, the less-expensive feed financially underperformed the other. Keywords: Litopenaeus vannamei, Biofloc technology, Hyper-intensive system, Feed, Economic viability |
