Genetic variability of wild and captivity populations of Colossoma macropomum (Cuvier, 1818) - doi: 10.4025/actascibiolsci.v34i2.7149

Carlos Henrique dos Anjos dos Santos, Marco Aurélio de Brito Leitão, Carolina Fernandes Silva de Sousa, Givanildo Ximenes Santana, Maria de Nazaré Paula-Silva, Vera Maria Fonseca de Almeida-Val

Resumo


Tambaqui (Colossoma macropomum) is among the most important fish species of the Amazon and one of the most cultivated in Brazil. In the present work we have evaluated the genetic variability of wild and captivity populations of C. macropomum. Enzymatic markers were used to estimate the genetic variability of 41 specimens from a wild group; and 30, 33 and 45 from three captivity groups, which came from Pentecostes (Ceará State), Jaboticabal (São Paulo State) and Itacoatiara (Amazonas State), respectively. Nine isoenzymic systems were used to evaluate the genetic variability of these populations. Using zimogram data we obtained the polymorphism level, allele number, allelic frequency, observed and expected heterozigosity, Wright F statistics (FIS, FST), genetic distance, level of similarity and group analysis. The isoenzymic data showed that, from the nine systems, six presented polymorphic loci (Fbp-2, G6pdh-2, G6pdh-3, Pgi-1, Pgi-2 and Pgm-1). The populations from Pentecostes and Jaboticabal presented loss of genetic variability and low heterozigosity, compared to the wild population and to the artificial population acquired at Itacoatiara fish farm. Based on these results and on fish farmer information we could consider the population from Itacoatiara as recently derived from a wild population. Concluding, we suggest that the artificial populations of tambaqui, which contain animals originated from this funding population at Pentecostes, should be renewed with the introduction of a new group of individuals with genetic variability equivalent to the wild population.


Palavras-chave


conservational genetics; isozyme; fish management; tambaqui

Texto completo:

PDF PDF (English)


DOI: http://dx.doi.org/10.4025/actascibiolsci.v34i2.7149



ISSN 1679-9283 (impresso) e ISSN 1807-863X (on-line) e-mail: actabiol@uem.br