Replacement of fish meal by animal by-product meals in a practical diet for growout culture of grouper (Epinephelus coioides)

This study was conducted to develop compounded feeds having a low content of fish meal for juvenile grouper and as an alternative to trash fish feeding. Epinephelus coioides juveniles were stocked in 36 units of 250-litre tanks at 25 fish/tank. Eight dietary treatments representing increasing (0, 10, 20, 30, 40, 60, 80 and 100%) percentage replacements of fish meal protein with 4:1 combination of meat meal and blood meal were tested in quadruplicate groups of fish arranged in a completely randomized design. Weight gain and specific growth rate (SGR), survival, food conversion rate (FCR) and body composition of fish were determined. Up to 80% of fish meal protein could be replaced by processed meat meal and blood meal, with no adverse effects on growth, survival and feed conversion efficiency of E. coioides juveniles. Use of animal byproduct meals as protein source substantially lowered the level of fish meal required in the juvenile grouper diet. The diet could be effectively used as a substitute for trash fish feeding, thereby reducing the requirements for fishery resource. From an economic standpoint, replacement of fish meal with cheaper animal byproduct meals in a practical diet for grouper could alleviate the problem of low fish meal availability and high cost.