Análise comparativa da variação genética entre os estoques cultivado e natural de Prochilodus argenteus: implicações para o repovoamento de rios

Abstract

Introduction of hatchery fish in river has been the major using strategy for river fishery rehabilitation, working to attenuate river damage in short time. But there are effective risks about their efficiency and results, concerning the pool gene preservation and illness proliferation, beyond others ecologies and economics aspects. At São Francisco river, during two decades it was used this kind of procedure with some species of fish, but there are no quantitative data about their efficiency. Prochilodus argenteus, popular known as Curimatápacu, is pointed as the most important economic specie at São Francisco basin, responsible for 50% of all fishery production. Therefore, this project goals to trace the genetic profile of a Prochilodus argenteus hatchery population, looking for identify stock genetic variability through 13 SSR loci previous described, and to compare theses data with others described in literature from wild stocks. Tests made with Microchecker, Genepop, and Fsat softwares detected low homozygosis; reduced allelic variability when compared with wild population; increase in heterozygosis when compared with expected; and negative inbreed coefficient, these data got a trace for bottleneck phenomena in a cultured population, and Bottleneck software tests confirm this hypothesis. When the same test was ruled with wild population data results very far from those found in hatchery populations, give a high reliability. To conclude, at cultured and/or management programs are necessary the knowledge of genetic profile population (hatchery or wild) to prevent damaging introgression in wild population and consequently extinction. These data can be used to made fishery river rehabilitation program more efficient, and so, adding with information to fish procreation, industrial fishery and biologic fish conservation studies.