Alfonso, E., Olivera, A., Beltrame, E.
Abstract:
Penaeid shrimp postlarvae production requires a considerable quantity of Artemia cysts. Apart from being costly, supply of them is unlikely to increase. The objective of this experiment was to determine the dosages of a commercial diet to feed Penaeus schmitti postlarva 5 to postlarva 10 in order to substitute Artemia nauplii partially.
The experiment was conducted in 12 plastic square tanks of 200 liters each containing 140 liters of filtered sea water. Stocking density was 100 PL5/L. The test included four treatments with three repetitions each:
- Pattern: Artemia nauplii (100%) + Artificial Plankton
- Artemia (50%) + Diet 12.5% (of the PL dry weight)
- Artemia (25%) + Diet 25.0% (of the PL dry weight)
- Diet 50% (of the PL dry weight)
Postlarvae were fed 12 times a day with the commercial diet and Artemia nauplii were adjusted three times a day. Microalgae (Chaetoceros calcitrans and Tetraselmis tetrathele) were also added.
The Analysis of Variance and Duncan Test (P<0.05) showed no significant differences for survival in all treatments, however, the PL growth was better when the Artemia nauplii were combined with the commercial diet (see table).
Results suggest that with the use of the commercial diet it is possible to substitute a 50% of the Artemia nauplii.
Treatment: Artemia (100%) +Artif. Pl - survival: 82.3% a - length: 5.66 mm a - dry weight: 2.23 g/10^4 a - biomass: 3.04 mg a
Treatment: Artemia (50%) + Diet (12.5%) - survival: 90.0% a - length: 5.69 mm a - dry weight: 2.23 g/10^4 a - biomass: 3.38 mg a
Treatment: Artemia (25%) + Diet (25%) - survival: 88.3% a - length: 5.69 mm a - dry weight: 2.06 g/10^4 a - biomass: 3.04 mg a
Treatment: Diet (50%) - survival: 76.7% a - length: 5.22 mm b - dry weight: 1.70 g/10^4 b - biomass: 1.60 mg a
(letters (a,b) denote significative differences)
(Laboratorio de Camaroes Marinhos, Centro de Ciencias Agrarias, Universidade Federal de Santa Catarina, P.O.Box 476, CEP 88040-970 Florianopolis, Santa Catarina, Brazil)
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