Avaliação econômica do uso de farelo da folha de mandioca na formulação de ração para juvenis de tilápias-do-Nilo (Oreochromis niloticus)

Abstract

Brazilian fish farming faces difficulties due to the high costs of commercial feed based on soybeans and corn. For this reason, the use of alternative feeds to replace those traditionally used may be a viable possibility to reduce costs in the formulation of fish feeds. Therefore, cassava leaf meal has emerged as an option to replace some ingredients. Thus, the objective was to evaluate the economic viability of including cassava leaf meal in the diet of juvenile Nile tilapia, replacing soybean meal. The experiment was conducted at the Experimental Aquaculture Laboratory (LEaQUA) located at the State University of Piauí (UESPI). A total of 240 juvenile Nile tilapia were obtained, already masculinized, with an initial average weight of 3.5 g. The experimental design was completely randomized, all distributed equally and evaluated in four treatments, with four replicates, with the experimental unit represented by 15 fish in 100-liter reservoirs. The four treatments consisted of: T1 - 0% inclusion of the formula; T2 - inclusion of 10% of the alternative protein adhered to the feed; T3 - 20% of the alternative protein; T4 - 30% of the protein. The experiment lasted 28 days of culture. The treatments 0%, 10%, 20% and 30% showed negative results in the net revenue (RL), operational cost (CO) and the profitability index (IL) which makes the inclusion of the alternative unprofitable for production, however it shows great aptitude for future economic viability in the treatment with 10% of cassava leaf meal (FFM).