Evaluation of the acceptability of diets formulated with hydrolyzed algae for juvenile abalone of Haliotis fulgens

Background. Abalones are aquaculture resources of great importance to the international food market. However, abalone cultivation faces a problem of food availability depending on the season, especially in Mexico. Goals. This study aimed to formulate diets for juvenile Haliotis fulgens from hydrolyzed algae. Methods. We evaluated the physicochemical parameters of the diets and their acceptability to juveniles H. fulgens. Three diets were formulated from different algae species: 1) Macrocystis pyrifera (MP), 2) Eisenia arborea (EA) and 3) mixture of both algae (MPEA). The total amount of hidrolyzed alga in each diet was 26%. Fresh E. arborea blades and the ABKELP^® commercial diet were used as negative and positive control, respectively. Finally, the toughness, stability and acceptability of each diet were determined at 3, 6, 9, 12 and 24 h. Results. The toughness and stability of all hydrolyzed algae diets were significantly different (p > 0.05) compared to the those of positive and negative controls. The toughness of the MP, EA and MPEA diets ranged from 600-630 g cm^-2, whereas the ABKELP diet was tougher (700 g cm^-2) after 24 h. The stability of the formulated diets was > 80%, while the ABKELP control reached 95% at 24 h. Overall ABKELP stability was significantly higher than those of the other diets (p < 0.01). The EA, MPEA, and ABKELP diets were more attractive to organisms than fresh E. arborea, although no significant differences in food intake were present (p < 0.05). Conclusions. All formulated diets exhibited physicochemical and acceptability characteristics that are suitable for H. fulgens.