SURVIVAL AND GROWTH OF Penaeus setiferus L. AND Penaeus aztecus IVES LARVAE FED Artemia BEGINNING AT THE PROTOZOEA-TWO SUBSTAGE VERSUS THE MYSIS-ONE SUBSTAGE

The following experiments compared survival and growth of shrimp larvae fed Artemia nauplii beginning at either the protozoea 2, protozoea 3 or mysis 1 substage. Experiment one compared survival and growth of larval Penaeus setiferus, from the protozoea 2 substage to three-day-old postlarvae, fed algae and either freshly hatched Artemia nauplii, decapsulated Artemia cysts or ultraviolet killed Artemia nauplii beginning at the protozoea 2 or mysis 1 substage. Survival was better for those postlarvae fed all three Artemia food types beginning at the protozoea 2 rather than the mysis 1 substage. Post-larval dry weights were similar, regardless of Artemia food type or the larval substage at which Artemia was introduced. Experiment two compared survival and growth of larval P. aztecus, from the protozoea 2 substage to two-day-old postlarvae, fed algae and live Artemia nauplii beginning at either the protozoea 2, protozoea 3 or mysis 1 substage. Controls were only fed algae. Survival was significantly better for those postlarvae fed Artemia beginning at the protozoea 2 substage. Post-larval dry weights increased with the introduction of Artemia nauplii beginning at the protozoea 2 substage. The potential effects of these results on current hatchery procedures are discussed.