PERFORMANCE AND PROFITABILITY OF P. vannamei IN SUPER-INTENSIVE BIOFLOC VS. RECIRCULATING AQUACULTURE SYSTEMS
Bianca Ramiro*, Otávio Augusto Lacerda Ferreira Pimentel, Taozhu Sun, Stephen Urick, Fernando H. Gonçalves, Jonathan Van Senten, Michael H. Schwarz, Wilson Wasielesky Jr and Dariano Krummenauer
Laboratory of Microorganism applied to Aquaculture, Federal University of Rio Grande – FURG - Rio grande - Brazil.
darianok@gmail.com
This study compared water quality, growth performance, and partial budget outcomes for Penaeus vannamei cultured in super-intensive Biofloc Technology (BFT) and Recirculating Aquaculture Systems (RAS) at the Virginia Seafood Agricultural Research and Extension Center, Virginia Polytechnic Institute and State University. A 69-day trial was conducted using 100-L experimental units in a completely randomized design with two treatments (RAS and BFT), each replicated three times. Shrimp were initially reared in a 30-day nursery to a weight of 0.10 ± 0.04 g and then stocked at 500 shrimp m-3. Biofloc growth in BFT was promoted by maintaining a C ratio of 15:1, adding dextrose when total ammonia nitrogen (TAN) reached 1 mg L-1. Probiotics (3 g m-3) were administered daily to both groups. TAN levels in BFT initially spiked but stabilized after 36 days. Vibrio abundance was initially higher in RAS, but by the end of the trial it was higher in BFT. Final weight, weight gain ratio, and yield were greater in BFT, whereas feed conversion ratio (FCR) and water use were higher in RAS. Survival rates were 83.33% in BFT and 88% in RAS. BFT achieved a superior net benefit/cost compared to RAS. Although RAS more effectively controlled nitrogenous compounds, BFT exhibited better zootechnical performance, with higher final weights, lower FCR, and better Vibrio management. The partial budget analysis indicated an economic advantage for BFT, with a net positive benefit of $2270.09 when shifting from RAS to BFT due to lower operating costs and higher shrimp yield.