MANAGEMENT OF SIZE VARIATION IN JUVENILE GILTHEAD SEA BREAM (SPARUS-AURATA) II - DRY FOOD TYPE AND LIVE DRY FOOD RATIO/

The effects of dry food type and live/dry food ratio on survival, grow th rate acid size distribution of juvenile gilthead sea bream were inv estigated. Dietary treatments consisted of a high (73.5%) and low (53. 2%) protein diet based mainly on squid meal vs, soybean and fish meal, respectively, while live food consisted of Artemia nauplii. The effec ts of the two dry food types and three live/dry food ratios were teste d over a period of 14 days, using a factorial experimental design. Sur vival was similar and high in all treatment combinations. Growth rate was affected by both food type and live/dry food ratio with a signific ant interaction between the two tested variables. Size distribution, m easured as the change in the coefficient of variation of mean weight ( Delta CV) was affected by both food type acid live/dry food ratio with a lack of an interaction between the two variables. Possible behavior al interactions and nutritional factors underlying these results are d iscussed. (C) 1998 Elsevier Science B.V. All rights reserved.