L. Vinatea, E.R. Andreatta-1997
Aquaculture, 154 : 247-259
Abstract:
Continuous and static water renewal strategies during larviculture of Penaeus paulensis (protozoea 1 to postlarva 1) were compared. Water renewal rates of 100, 200 and 300%/day, and stocking densities of 200 and 350 larvae/l were tested. The experimental design used was a 2 x 3 x 2 factorial, arranged in blocks (replications) at random. The results showed that larval survival (%), dry weight (micro g per larva), surviving biomass as dry weight (mg/l) and metamorphosis rate (percentage of postlarvae present by the end of the culture period), were significantly (P<0.05) higher with the static renewal strategy, a stocking density of 200 larvae/l and a renewal rate of 100%/day. Non-ionised ammonia nitrogen (NH3-N) and nitrite nitrogen (NO2-N) compounds did not exceed safety levels recommended in the literature in any of the treatments. The heterotrophic flora composed of Pseudomonas sp. was present at a higher level in the cultures with static renewal strategies. If the larvae supplemented their nutrition with Pseudomonas, this might explain the better performance of this strategy.
(Laboratorio de Camaroes Marinhos da Barra da Lagoa, Dpto. de Aquicultura, CCA, Universidade Federal de Santa Catarina, Florianopolis, 88.049.970, SC, Brazil)
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