A highly efficient microencapsulated food for rearing early larvae of marine fish

This paper describes the process of elaboration and the characteristics of an inert microencapsulated diet which provides much improved growth and development in the rearing of gilthead seabream larvae. The microencapsulated diet was composed of casein, fish protein hydrolysate, octopus meal, dextrin, emulsified lipids and a vitamin mixture. Following 4 days feeding on rotifers, three rearing treatments were used from day 8 to day 15 after hatching: Regime A (control): larvae fed on rotifers in semi-open system; Regime B: larvae fed on microcapsules and reared in a semi-open system; Regime C: larvae fed on microcapsules and reared in a closed recirculating water system. Growth rate and survival were similar in the three treatments (growth rates: 0.13, 0.09 and 0.12 day-L, respectively), and notably higher than those obtained with the previous prototype. The results clearly show that the present microencapsulated diet was able to substitute for live food during the early stages of larval rearing and hence can be used as an excellent tool for investigation of the nutritional requirements of marine larval fish. (C) 1999 Elsevier Science B.V. All rights reserved.