Validation of 12 species-specific, tetrasomic microsatellite loci from the Russian sturgeon, Acipenser gueldenstaedtii, for genetic broodstock management

Abstract

The Russian sturgeon, Acipenser gueldenstaedtii, is a critically endangered fish species. Hatcheries are operated in several countries within its natural range to produce stocking material for release into the wild and also for aquaculture purposes (caviar and meat production). An appropriate genetic broodstock management (plan or strategy) is required to avoid negative effects, e.g., admixture and hybridization of genetically differing stocks or loss of genetic variability due to inbreeding and genetic drift. Therefore, 11 tetrasomic microsatellite loci were newly isolated from the Russian sturgeon genome and arranged together with an already known locus into four multiplex PCR sets. These microsatellites were used to characterize three groups of hatchery juveniles from Germany (aquaculture production), Turkey, and Romania (production of stocking material) as well as a group of wild-caught adults from the Danube River, Romania. Based on the variability within groups, measured by the mean number of alleles per locus and expected heterozygosity, and the differentiation between groups, measured by Nei’s GST and genetic distance D, the ability of the 12 loci to detect unwanted reductions in genetic variability within hatchery juveniles and to differentiate between groups could be demonstrated. This set of loci can also be used to identify those pairs of spawners that transmit the highest possible genetic variability to the next generation.