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Submitted to: International Aquaculture Meeting
Publication Type: Abstract Only Publication Acceptance Date: 7/30/2004 Publication Date: 8/25/2004 Citation: Green, B.W. 2004. Production of Litopenaeus vannamei in freshwater supplemented with key ions. In: VII Central American Aquaculture Symposium, August 25-28, 2004, Tegucigalpa, Honduras. p. 53. Interpretive Summary: Not required Technical Abstract: The Pacific white shrimp (Litopenaeus vannamei) is being cultured far from coastal areas in ponds that have been filled with low-salinity (2-5 ppt) ground water or brine transported from the coast and diluted on site. Deficiencies in one or more ions have been implicated in poor growth and survival of shrimp in ponds filled with low-salinity groundwater. Addition of specific fertilizers to augment concentrations of specific deficient ions appears to solve the problem. Since deficiencies of one or several ions in low-salinity ground water can be corrected, it should be possible to add key ions to freshwater to allow successful culture of L. vannamei. A study was conducted in three 0.1-ha earthen ponds to determine whether L. vannamei could be grown to market size in ponds where concentrations of key ions were augmented to levels similar to dilute seawater at 0.8 ppt. The ponds were filled with freshwater and salinity was increased to 0.7'0.8 ppt through addition of salt and potassium fertilizer. Stock salt applied at 5,200 kg/ha supplied sodium and chloride, while potassium fertilizer (0-0-22, 11% Mg, 22% S) applied at 3,100 kg/ha supplied potassium, magnesium, and sulfate. Ponds were stocked with PL15 shrimp (39 PL/m2), which were fed a commercially formulated shrimp diet (35% crude protein), 7 d/wk. Each pond was equipped with a 0.37-kW electric paddlewheel aerator and aerated nightly to maintain dissolved oxygen concentrations above 3.0 mg/L. Addition of stock salt and potassium fertilizer raised concentrations of selected ions to levels that allowed shrimp to survive and grow. Pond salinity averaged 0.7 ppt throughout the grow out cycle. After 125 days of grow out, gross shrimp yield averaged 3,449 kg/ha and individual weight averaged 19.3 g/shrimp. Shrimp survival averaged 47%. |
