Feed ingredients of aquatic animal origin such as fishmeal, krill meal, shrimp meal and squid meal are rich in chemical compounds such as free amino acids (FAA), nucleotides, amines and nucleosides that are readily recognizable by the chemosensory systems of the fish in the process of locating and ingesting food. Rendered animal and algae proteins are a potential source of digestible protein, amino acids (AAs), vitamins and minerals. This study was conducted to evaluate the attractability and palatability of chicken feather and algal meals to replace fish meal, in the formulated diets for juvenile of seabream, Sparus aurata.
Treated chicken feather meal with 20, 35 and 50% replacement of fish meal (20, 35, 50 CHF), algal meal (Ulva fasciata) with 20 and 35% replacement of fish meal (20, 35 AM) and control diet (CNL) were tested for attractability and palatability to juvenile gilthead seabream, Sparus aurata.
Algal meal accorded considerable feeding effector properties to seabream feeds at high levels of inclusion (20 and 35% AM), but is probably only slightly superior to fishmeal in terms of attractability and palatability. Chicken feather meal was not an effective feeding effector to seabream at 20, 35 and 50% inclusion level. However, 50% CHF was more palatable than CNL, 20 and 35% CHF. Overall, 20 AM is the best diet in terms of both attractability and palatability. Among the various biochemical parameters analyzed in the present study, levels of algae replacement in the ingredients closely related with the effectiveness of the ingredients as attractants and palatability enhancers for seabream.