The effects of the amount of feed delivered and stocking density were investigated in the production of white-leg shrimp Penaeus vannamei reared under intensive conditions. Three experiments were conducted, each over 91 days, from stocking with PL 12 to harvest, a period comparable to commercial production. All experiments were conducted in indoor tanks of 7.5 m3 volume with 5 replicate tanks per treatment. In the first experiment, shrimp were stocked at 100 shrimp/m2 (700 shrimp per tank) and fed either 16 g or 23 g of feed per individual over the course of the experiment. In the second experiment, shrimp were stocked at 150 shrimp/m2 and fed 17, 22 or 24 g of feed per individual. The third experiment was stocked at 150, 200, 250 and 300 shrimp/m2 and all treatments were fed at 24 g per individual.
For Experiments 1 and 2, growth increased with increasing amount of feed provided, increasing from 16.6 g to 22 g for Experiment 1 and 16.3 g; 20.1 g and 21.5 g for the respective treatments in Experiment 2. The amount of feed provided had no affect on shrimp survival. Feed conversion ratio (FCR) increased slightly with increasing feed (1.08 to 1.13 for Experiment 1; 1.17, 1.22 and 1.25 for respective treatments in Experiment 2). Further analysis will be conducted to investigate divergence of growth trajectories and how well this matches the allometric scaling requirements of the animal for both protein and energy.
Results from Experiment 3 showed that increasing the stocking density of P. vannamei from 150 to 300 shrimp/m2 had no significant effect on the growth of shrimp, with all treatments having an average final weight of approximately 20 g, and no significant effect on survival (average 85%). Our research indicates that P. vannamei can be successfully grown at high densities, up to 300 shrimp/m2 and be fed to 24 g of feed per individual per 91 days under experimental conditions with little effect on survival or FCR.