USE OF BIOFUEL BY-PRODUCT FROM THE GREEN ALGAE Desmochloris sp. AND DIATOM Nanofrustulum sp. MEAL IN DIETS FOR NILE TILAPIA Oreochromis niloticus

Abstract

Algal by-product meals from the Hawaiian biofuels industry were evaluated as ingredients in diets for juveniles of Nile tilapia (Oreochromis niloticus). Four experimental diets were formulated to fulfill fish nutritional requirements. The diets were made with fish meal, soybean meal, whole diatom (Nanofrustulum sp.) meal, or defatted green algae (Desmochloris sp.) meal as the test ingredients. A feeding experiment with juvenile tilapia of 2.6 ±0.1 g initial weight was carried out in a freshwater recirculation system with each diet treatment tested in triplicate tanks. Fish were fed the experimental diets to apparent satiation twice a day for 12 weeks and fish weight was measured every three weeks. Water temperature was maintained at 22.7 ±0.8 °C, salinity at 0.1 ±0.0 ppt and dissolved.