Weaning strategies for striped trumpeter, Latris lineata, postlarvae culture

The striped trumpeter, Latris lineata, is a native fish being developed for aquaculture in Tasmania, Australia. Striped trumpeter have a long postlarval stage and rearing has been reliant on the long-term use of Artemia. Two experiments were conducted to investigate weaning strategies. The first experiment used 52 d posthatch (dph) postlarvae previously reared on Artemia from 16 to 52 dph enriched with either low or high ascorbic acid. The treatments were Artemia, a microdiet, or cofeeding. The postlarvae were reared until 67 dph. The Artemia treatment yielded significantly higher mean survival, followed by cofeeding, and the microdiet. Feeding Artemia yielded significantly heavier postlarvae and the microdiet produced significantly smaller postlarvae. A second experiment used 41 dph postlarvae and investigated the effect of cofeeding duration prior to feeding with Artemia and microdiet as controls. Cofeeding periods of 5, 10, and 15 d were tested. Cofeeding for 5 d and microdiet feeding yielded significantly poorer survival compared with Artemia. Artemia feeding yielded significantly heavier postlarvae. In both experiments, the diets did not have a significant effect on jaw morphology. These experiments are the first to examine weaning strategies for striped trumpeter postlarvae and suggest cofeeding postlarvae from 40 dph and feeding microdiet exclusively at 50 dph.