Feeding frequency affects food consumption, feeding pattern and growth of juvenile yellowtail flounder (Limanda ferruginea)

Feeding experiments were carried out on juvenile yellowtail flounder (Limanda ferruginea) (6.8 +/- 0.2 g), a candidate for cold-water aquaculture in eastern North America. At about 7 degreesC, feeding frequency was shown to have a significant (P < 0.05) effect on food consumption and growth, with fish fed to apparent satiation in two or four daily meals consuming more food and growing better than fish fed less often (once daily and two meals every other day). Fish fed two meals every other day ate significantly more ( P < 0.05) in the morning (8.4 +/- 0.4 mg) than in the afternoon (6.0 +/- 0.2 mg), whereas there were no differences in meal sizes between feedings for other groups. Behavioural observations revealed that fish fed fewer meals per day ingested more pellets per feeding (1.1 +/- 0.1 vs. 0.7 +/- 0.1 pellet/min), showed more activity and foraged more often throughout the day than fish fed four times daily or twice daily (3.5 +/- 0.3 vs. 2.1 +/- 0.2 behaviour/min). Low incidences of aggression indicated that yellowtail flounder probably do not form feeding hierarchies; however fish fed twice daily showed a significant increase in the coefficient of variation (CV) for body weight over the course of the experiment (P < 0.05). Fish fed twice daily gained significantly more weight (P < 0.05) and had the lowest FCR (0.89), thus it is recommended that fish at this stage of grow-out be fed twice per day. (C) 2002 Elsevier Science B.V All rights reserved.