Profit Indices in Nile tilapia (Oreochromis Niloticus L.) Fed on Peanut-Based Meals as Alternatives to Dietary Fishmeal in Grow-Out Earthen Ponds

Abstract

Persistence of dietary fishmeal probably accounts for the low profitability in farmed Nile tilapia in Uganda. A 24 week field study was conducted in Busoga sub-region of Eastern Uganda to compare profit indices in pond cultured Nile tilapia fed on peanut-based meals as alternatives to dietary fishmeal. It consisted of an experiment and sample survey that targeted fish biomass production and input-output valuation respectively. Each of the 12 earthen ponds measuring 12 cubic meters were stocked with 48 ‘all male’ Nile tilapia (Oreochromis niloticus L.) fingerlings of mean initial weight of 21.7 grams. Iso-nitrogenous diets containing 30% and 25% Crude Protein were applied for the first eight and last four respectively. Dietary treatments included fishmeal-based diet and two peanut-based diets; peanut meal-based diet and mixed plant-based diet. Profit indices for the fishmeal and mixed plant-based- diets were not significantly different (p>0.05). On the contrary, the Profit index characteristic to the PNM-based diet was significantly lower (p≤0.05) than the other test diets. Accordingly, the mixed plant meal should be used for complete substitution of dietary fishmeal in pond cultured Nile tilapia.