MATURATION PERFORMANCE OF PENAEUS-VANNAMEI CO-FED ARTEMIA BIOMASS PREPARATIONS

Few shrimp hatcheries successfully propagate captive broodstock on a c ommercial scale. Diets for acceptable maturation performance of Penaeu s vannamei have typically relied on the inclusion of marine polychaete s (bloodworm) from Panama or Maine, USA, which are expensive and are o f unpredictable supply. Studies were therefore undertaken at experimen tal and commercial scale to replace or supplement the polychaetes by f rozen ongrown Artemia which were either non-enriched or bioencapsulate d with specific boosters, In experiment 1 the control diet consisted o f frozen squid only and was evaluated against broodstock diets where 6 0% of the squid was substituted by bloodworm or enriched Artemia bioma ss. Effects were evaluated for males and females as sexes were kept in separate broodstock tanks. In experiment 2 the control treatment rece ived a mixture of natural feed, including bloodworm. For the two other treatments, the bloodworm fraction was replaced by non-enriched and e nriched Artemia adults, respectively, Finally, an evaluation at commer cial scale was made comparing two feeding regimes based on a combinati on of semi-moist pellets and fresh-frozen marine organisms, In one of the treatments a portion of the natural food was replaced by an equal amount of enriched, frozen Artemia biomass. Dietary effects on the rep roductive performance of the broodstock were evaluated and egg charact eristics were monitored. Results from the three experiments confirm th at dietary conditions affect the reproductive performance of P. vannan ei. Even in a maturation diet consisting of multiple natural food prod ucts, frozen adult brine shrimp biomass appears to increase reproducti ve performance. Although the male diet did not appear to significantly affect mating or fertilization, there was a clear tendency towards im proved mating success and hatching when Artemia biomass was included i n a mixed dirt. Combined effects of improved mating and hatching resul ted in significant differences in overall nauplii production. It is th erefore concluded that Artemia biomass may be useful as a supplement t o or as a replacement for polychaetes in vannamei maturation diets. (C ) 1997 Published by Elsevier Science B.V.