DNA microsatellite markers for "dourada" (Brachyplatystoma rousseauxii, Siluriformes: Pimelodidae), a migratory catfish of utmost importance for fisheries in the Amazon: Development, characterization and inter-specific amplification

Abstract

The long-distance migratory catfish Brachyplatystoma rousseauxii is among the two most important commercial catfish in the Amazon region. Recent data lists this species as being affected by overfishing. Thirty polymorphic microsatellite loci were isolated and characterized in 35 individuals. The number of alleles per locus ranged from 2 to 22, with an average of 9.87. The observed (HO) and the expected heterozygosity (HE) ranged between 0.143-0.914 (average 0.636) and 0.215-0.929 (average 0.706), respectively. Five loci showed a significant deviation from the Hardy-Weinberg Equilibrium and linkage disequilibrium was detected between loci BR68/BR44, BR68/BR48 and BR68/BR61. Cross-amplification in six con-generic species resulted between 12 and 21 polymorphic loci, depending upon the species. These polymorphic microsatellites should be useful for management policies of B. rousseauxii in the Amazon as well as for the others Brachyplatystoma species of commercial value. © Springer Science+Business Media B.V. 2009.