Research and extension walk together in Vale do Ribeira region

Abstract

It is not possible to compete with other regions of Sao Paulo, mainly because of large scale and high technology of these locations. We have to adequate the regional productive reality, to explore and increase new markets, what is already occurring in a small scale with São Paulo region schools supply with processed fish products, like kibe and croquette for children feeding. The aim of this study is to find an adequate combination among fish species for production, production system, fish management and business management to allow and enable fish products provision for children feeding at school. The present study will be developed in six fish cultures, during two aquaculture production cycles, at Cajati, Jacupiranga, Sete Barras and Juquiá towns, and one model centre at APTA Pólo Regional do Vale do Ribeira in Pariquera-Açu town. The project is based on the direct participation of farmers in all phases of the project implementation. This participation will occur by the local association AQUIVALE, and the five fish farmers chosen will be responsible together with the technical team for the development and evaluation of project activities. We will test three species of fish that are already introduced in Vale do Ribeira, grass carp, pacu and Nile tilapia in the stocking density of two fish/m2. To determine pond water quality of the five farms and of the centre, it will be collected every 15 days water of input, output and inside the ponds. The collection will be done at 9 AM with field measures of dissolved oxygen (digital portable oxymeter), water temperature (thermometer) and water transparency (Secchi Disc). Water samples will be collected with Van Dorn bottles for laboratory determination of total alkalinity, hydrogenionic potential (digital pH meter) and electric conductivity (digital conductivity meter). For determination of dissolved nutrients concentration, part of the samples will be filtered and frozen for posterior analyses of ammonia concentratio, the other part of not filtered water will be frozen for posterior determination of total phosphorus and total nitrogen. Every month a fish sample will be weight and length measured. Obtained date will be useful for productive performance evaluation (average final weight, weight gain, food conversion, survival, final biomass and biomass by area) and feeding adjustments (ration quantities, granulometry, and protein content) based on pond biomass, development phase and fish species. Food will be offered twice daily, in the morning and in the afternoon, in the proportion of 3% of the biomass for fish till 100g of live weight and 2% of biomass till final weight of rearing. At the end of the first production cycle it will be done an economic evaluation, considering the following items: productive cycle in months; fi8nal fish biomass production; total use of ration for fish production; ration cost; average market price of fish per kg; labor hours per productive cycle; Nile tilapia price per thousand juvenile; linear depreciation of rearing installations; production capital; net capital gain and total operational cost. Based on these production results we will be able to introduce good practices of business and fish production management for Vale do Ribeira small farmers, overcoming the challenge of the activity consolidation, allying environmental preservation and upgrade of productivity indices. (AU)