Comparative utilization of rendered animal derived products with or without composite mixture of soybean meal in hybrid tilapia (Oreochromis niloticus × Oreochromis mossambicus) diets

The results of trial 1 showed that fish fed poultry by-product meal (PBM) had the best productivity values of weight gain, feed conversion ratio, specific growth rate and protein efficiency which were not significantly different (P ≥ 0.05) from values obtained for fish fed the fish meal based (control) diet. Fish fed the enzyme treated feather meal in both trials 1 and 2 had higher values of growth performance and nutrient utilization than corresponding fish fed the hydrolyzed feather meal. However, composite mixture of hydrolyzed feather meal with soybean meal had considerable improvement on fish growth and nutrient utilization while there was no significant changes in the productivity values of fish fed enzyme feather meal with or without soybean meal dietary inclusion. Fish fed blood meal had the poorest productivity values but similar to fish fed hydrolyzed feather meal in weight gain and protein efficiency.