A12-week feeding trials were conducted to evaluate the nutritive value of two forms of palm cull date and date pits as energy sources, supplemented with feed additives (Phytogenics), to be partially replaced (13.5%) yellow corn
in feeding Nile tilapia fingerlings. Twelve experimental isonitrogenous (30.43% crude protein), isocaloric (436.43 kcal GE 100g-1) experimental diets were formulated taking into account energy sources and feed additives. Concerning
energy source, four experimental diets were formulated which contain: yellow corn (YC) as control diet, dried cull date (DCD), wet cull date (WCD) and date pits (DP). As for feed additives (flavorings), three dietary sub-groups were builtup
in each group to include: zero additives, 0.03 % Digestarom® (DG) and 0.03 % Marjoram leaf extract (MLE). Ten fingerlings (10.55 ± 0.30 g) were stocked/aquarium; two replicates per treatment and fed twice daily (six days) at
3% of body weight for 84 days.
The results indicated that the partial replacement (13.5%) of WCD instead of YC supplemented with or without feed additives increased fish specific growth rate and feed utilization. However, replacement either DCD or DP
decreased tilapia performances; meanwhile DP recorded the worst values. On the other hand, DG supplementation improved fish performances either fed WCD-based diets or control diets (YC). It could be concluded that wet cull date
may be cost-effective when partially replaces yellow corn in tilapia diets as energy source, and improves fish performances when supplements with 0.03 % Digestarom®.