Wouters, R., Van Hauwaert, A., Naessens, E., Ramos, X., Pedrazzoli, A., Lavens, P.-1997
Aquaculture International, 5 (2) : 113-126
Abstract:
The influence of varying dietary n-3 HUFA concentrations and ratios of 22:6n-3/20:5n-3 (DHA/EPA) on culture performance and fatty acid composition of white shrimp (Penaeus vannamei) larvae and postlarvae was verified in two experiments. In a first experiment, shrimp (zoea 2-postlarvae 11) were fed rotifers (Brachionus plicatilis) and Artemia spp. nauplii that were enriched with different self emulsifying concentrates: one HUFA-free coconut oil (T1), and three iso-HUFA concentrates with DHA/EPA ratios of 0.6 (T2), 2 (T3) and 4 (T4), respectively. In a second experiment, postlarvae were fed for 25 days (starting from postlarvae 10) on isolipidic semi purified diets: one HUFA free control (TA), and four iso-HUFA diets with DHA/EPA ratios of 0.6 (TB), 0.9 (TC), 1.8 (TD) and 3.64 (TE), respectively. Experiment 1 revealed no significant differences in production characteristics, except that resistance to a countercurrent stress in postlarvae 11 was significantly lower in T1 than in T2 and T3 (p < 0.05). In experiment 2, postlarvae of TA had a significantly lower dry weight than the other treatments at the end of the trial. The effect of the DHA/EPA ratio within the experimental limits could not be demonstrated. Analysis of the fatty acid composition of the shrimp showed notable changes of n-3 HUFA concentrations during the metamorphosis from mysis to postlarvae, and a different response to the dietary concentrations of DHA compared to EPA.
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