The effects of feeding commercial feed formulated for semi-intensive systems on Litopenaeus vannamei production and its profitability in a hyper-intensive biofloc-dominated system

摘要

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$0.99kg^-^1) formulated for semi-intensive systems and the more expensive (US$1.75kg^-^1) which was designed for hyper-intensive systems. A 67-days study was conducted in six 40m^3 lined with Ethylene Propylene Diene Monomer membrane raceways (RWs) filled with mixture of seawater (22m^3), and biofloc-rich water (18m^3). Each RW was stocked (500shrimpm^-^3) using juveniles (2.66g) 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.