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561.
Armando García-Ortega Johan Verreth Karen Vermis Hans J. Nelis Patrick Sorgeloos Martin Verstegen 《Aquaculture International》2010,18(2):119-134
Temporary accumulation of ascorbic acid 2-sulfate (AAS) was measured to estimate food intake and gut evacuation in larvae
of African catfish. Fish larvae were fed decapsulated cysts of Artemia containing AAS. In a first experiment it was found that no biosynthesis of AAS occurs in the larvae of this species. In a
second experiment, the gut contents of the fish larvae fed were calculated as they changed during development. In a third
experiment, the gut evacuation rate of fish larvae was determined during continuous and discontinuous feeding regimes in the
first five days after the start of exogenous feeding. Food consumption by catfish larvae increased from 46.5% of their body
dry weight (BDW) on day 1 after the start of exogenous feeding to 53.8% BDW on day 3. Thereafter, food consumption decreased
to 27.8% BDW on day 5. A similar pattern was observed for gut evacuation, which increased during the first days of exogenous
feeding and decreased as fish growth continued. The rate of gut evacuation in a continuous feeding regime was significantly
higher (P < 0.05) than that under discontinuous feeding. On day 1 post-hatch and 7 h after first food ingestion the fish larvae evacuated
87% of the food in continuous feeding compared with 43% under discontinuous feeding. It was found that gut emptying differs
during larval development. Under continuous feeding, on days 1 and 3 post-hatch and 11 h after the first meal 90% of the food
was evacuated compared with 71% evacuated on day 5. The advantages and limitations of the AAS method for estimation of food
consumption by fish larvae are discussed. 相似文献