Pacific White Shrimp
Tzachi M. Samocha, Eudes S. Correia, Josh S. Wilkenfeld, Tim C. Morris, and Terry Hanson
Production of Litopenaeus vannamei has been limited by disease epizootics and restrictions governing releases of mariculture effluent waters. The presence of viral pathogens in natural waters suggests that exchanging pond water may allow their introduction into cultured shrimp stocks resulting in massive crop losses. Shrimp culture in limited discharge recirculating systems can reduce the risk of disease introduction and the negative environmental impact associated with effluent discharge. Furthermore, culture of fresh never frozen high-quality shrimp in these systems in the US can significantly increase food biosecurity while minimizing potential competition from cheap foreign imports.
A 108-d grow-out study was performed with juveniles (0.99±0.17 g) of the Pacific White Shrimp, Litopenaeus vannamei restocked (450 shrimp/m3) in four 40 m3 RWs with water used earlier in a 62-d nursery study. To make super intensive shrimp farming more competitive, the objectives of this study were to evaluate the effect on water quality and shrimp performance of two inexpensive methods for controlling particulate matter concentrations. Two RWs were equipped with foam fractionators (FF) and two with settling tanks (ST). Shrimp were fed a commercial 35% CP diet (HI 35, Zeigler Bros., Gardners, PA). The study showed that use of FF and ST was effective in controlling particulate matter and providing suitable growing condition for the shrimp. No statistically significant differences in shrimp final mean weight (21.9-22.4 g) were found between treatments. Survivals in all four RWs were high (94.5-96.8%). Growth was between 1.35 and 1.39 g/wk, FCR between 1.53 and 1.60. Shrimp yield was between 9.34 and 9.75 kg/m3. Water use was between 98 and 126 L/kg of shrimp produced. No significant differences were found between treatments in all of these indicators.
An economic analysis based on this study suggests improved profitability compare to results obtained in 2007. Production results were combined with current input and output costs to simulate a commercial-scale operation. The operational scale included one greenhouse housing eight (500 m2/m3) grow-out RWs and two nursery RWs (500 m2/m3) which included appropriate machinery and equipment should cost a total initial investment of $992,000. The calculated variable cost of producing shrimp was $4.82/kg; fixed cost of production were $0.70/kg, and the total production cost was $5.52/kg of shrimp produced. The selling price for shrimp used in this simulation was $7.20/kg for 46-55 count/kg (21-25 count/lb); feed cost was $1,095/metric ton; and PL were valued at $19.52/1,000. Based on an expected 3.7 crops per year there was a net return of $1.68/kg; ten year net present value was $1.08 million; internal rate of return for the 10-year simulation was 32.8%; and a 2.8 year payback of initial investment was calculated.
Texas A&M AgriLife Research Mariculture Laboratory
4301 Waldron Rd.
Corpus Christi, TX 78418