Recent genetic changes in enhanced populations of sea trout (Salmo truttam.trutta) in the southern Baltic rivers revealed with SNP analysis

Abstract

-The genetic structure of a fish population is usually thought to be stable over time. In the southern Baltic, Salmo trutta m. trutta (sea trout) populations have been characterized by low degree of genetic differentiation. All studied populations had been heavily stocked with mixed material for many years prior to the sampling period, including releases of Pomeranian sea trout to the Vistula River in Poland, Southern Baltic. However, the strategy of stocking became river based a few years before the sampling began. Juveniles from artificial reproduction are released only to their parental river, which reduces the mixing of the gene pool of fish from different populations. Changes in sea trout populations in the southern Baltic over time were studied using single nucleotide polymorphisms (SNPs). Genetic composition of populations of sea trout in the Vistula and Drwȩca river system were found to increasingly resemble the non-admixed hatchery population from Aquamar (Miastko, Poland), whereas the Pomeranian populations were stable. The implementation of a new stocking strategy for the restoration and protection of Vistula sea trout was noted as possible explanation. With the increase of natural breeding, artificial enhancement of sea trout populations should be reduced.

Genetic Diversity and Structure Analysis of Percocypris pingi (Cypriniformes: Cyprinidae): Implications for Conservation and Hatchery Release in the Yalong River

“…pingi may provide some practical guidance for conservation strategies such as hatchery release. Since releasing hatchery fish that are genetically divergent with the wild may cause disturbance to the population structure of the wild populations, it is reasonable to release hatchery individuals to river where their parental fish were first captured [65]. …”

Single nucleotide polymorphism markers with applications in aquaculture and assessment of its impact on natural populations

“…An Atlantic salmon derived SNP-array was also used for the genotyping of two populations of Southern Baltic Sea trout S. trutta m. trutta and a diagnostic panel of 39 SNPs was selected for further population genetic analyses and identification of changes related to stocking (Drywa et al, 2013;Pocwierz-Kotus et al, 2014;Wenne et al, 2016b, Wenne et al, 2016c. Large numbers of SNP markers obtained with NGS was used for genome-wide diversity assessment of wild Mediterranean brown trout S. trutta populations and from Atlantic and Mediterranean hatchery-reared strains in southern France that had used for stocking (Leitwein et al, 2016).…”

Genetic structure of important resident brown trout breeding lines in Poland

“…Lerceteau-Köhler et al 2013), Hungary (Ősz et al 2018), Poland (e.g. Wenne et al 2016), Slovenia (e.g. Jug et al 2005), and Switzerland (e.g.…”