Human influence on the native brown trout (Salmo trutta) genepool in the continental Western Croatia

Abstract

The negative anthropogenic influence on the autochthonous brown trout was recorded in a large part of the Balkan Peninsula. The major threat to native populations is spreading of the Atlantic phylogenetic lineage of brown trout which isincreasingly present in streams and riversattractive for fishing. Assessment of the state and presence of haplogroups at sevenlocalitiesin the continental Western Croatia was done using two genetic markers,the control region of mitochondrial DNA (CR mtDNA) and gene lactate dehydrogenase (LDH-C1*).Out of a total of 86 analysed samples, according to the CR mtDNA analysis, 59 of them belong to the Danubian phylogenetic lineage with the dominant Da1 haplotype, and the rest of the samples belongto the Atlantic lineage,having the At1 haplotype. The restriction analysis of the gene locus LDH-C*showed that hybridizationbetween individuals of different phylogenetic lineagesexists and recorded in almost half of the tested samples.