Effect of using taro leaves as a partial substitute of soybean meal in diets on growth performance and feed efficiency of the Nile tilapia Oreochromis niloticus.

Abstract

This experiment was conducted to evaluate the effect of using taro leaves meal (TLM) as a partial substitute of soybean meal (SBM) in fish diets on growth performance and feed utilization of Nile tilapia Oreochromis niloticus (6.00g). Five experimental diets were formulated to contain isonitrogenous (29% crude protein) and isocaloric (4.27 kcal/g diet) as follows: control and different levels of taro leaves replaced 10, 15, 20, or 25% soybean meal. Each diet was fed in triplicate groups two times a day for 8 weeks to apparent satiation. Results demonstrated that growth performance parameters (final body weight, weight gain, specific growth rate, and survival rate) were increased significantly with increasing taro leaves meal (TLM) in fish diets. Maximum growth was obtained when fish fed on a diet containing 20% of TLM. No significant differences (P > 0.05) were found in the survival rate among treatments. Values of feed efficiency parameters were increased significantly with increasing TLM in fish diets and the highest values were recorded with fish fed on a diet contained 20% of TLM. Results indicated that fish proximate chemical analysis affected significantly by partial replacement of TLM for SBM in fish diet. Moreover, results showed that the incorporation of TLM (10% to25%) in the fish diet reduced the price of one kg diet as compared to the control group. These results suggest that taro leaves meal could substitute up to 20% of soybean meal in the Nile tilapia diet without any adverse effects on growth performance or feed efficiency and with an economic return and reduced the feed cost.