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Four mitochondrial DNA segments, ND1, ND6, cyt b and D-loop, were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in 14 tench (Tinca tinca L.) populations located in Europe and Asia; data on 5 Italian populations previously analyzed for the same mtDNA segments were also included in the study. All the considered segments were polymorphic and originated a total of 9 composite haplotypes which were clustered into 2 haplogroups, A and B, possibly corresponding to the Western and Eastern phylogroups previously described in tench. Nine out of 19 populations showed polymorphism, with haplotype diversity ranging from 0.246 to 0.643 and nucleotide diversity from 0.009 to 0.078. Seventy-five percent of the pairwise comparisons were significant, indicating a high between-population variability. The Neighbour-Joining tree revealed the presence of 3 clusters, including pure populations, with only a A or B haplogroup, and mixed populations, with both haplogroups. The possibility of identifying populations with different haplotypes has practical implications for both conservation and supportive stocking. [ABSTRACT FROM AUTHOR]

The Tinca Gobba Dorata del Pianalto di Poirino (Golden humped tench of Poirino highland, [PO]), the only Italian fish with the Protected Designation of Origin, was characterized by seven microsatellites and compared to three wild populations living in Italian lakes (Valagola [VA]; Trasimeno [TR]; Bolsena [BO]). The PO population showed high variability values (number of effective alleles: 2.70 vs. 1.62 to 2.20; expected heterozygosity: 0.49 vs. 0.29 to 0.40). The analysis of between-population differentiation indicated that PO significantly differed from the others (FST = 0.039 to 0.097, P<0.05), while BO and TR were the most similar, consistently with their geographic proximity. The Neighbour-Joining tree revealed a clear separation between Northern and Central populations, with a bootstrap support of 97%. The population differentiation was reflected by the results of the assignment test, with 64% to 92% of the individuals correctly assigned to the original population, and a probability ranging from 76% to 95%. No individuals belonging to other populations were erroneously assigned to PO. A more detailed analysis of the PO population showed a similar genetic variability within the 15 considered ponds and a low degree of differentiation between ponds, with the exception of one "historical" pond, which significantly differed from most of the others, thus deserving to be preserved. The results indicate that the PO, despite being farmed, has a high level of withinpopulation diversity and is greatly differentiated from the other populations considered. The possibility of applying the assignment test in the framework of the product traceability deserves further investigation. [ABSTRACT FROM AUTHOR]

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In order to facilitate studies on the genetic structure of wild populations as well as to monitor genetic changes in cultured stocks, nine polymorphic microsatellite loci were isolated from pike-perch ( Sander lucioperca). Single loci allele numbers varied between two (loci MSL-3 and MSL-7) and six (loci MSL-1 and MSL-2), and observed heterozygosities ranged from 0.36 (locus MSL-2) to 1.00 (locus MSL-9) in a test panel of 25 individuals. Only one pair of loci ( MSL-5 and MSL-8) displayed significant linkage disequilibrium after sequential Bonferroni corrections. Hardy–Weinberg tests revealed significant excesses of heterozygotes at three loci ( MSL-1, MSL-7, and MSL-9). [ABSTRACT FROM AUTHOR]

Jelena Lujić, Klaus Kohlmann, Petra Kersten, Zoran Marinović, Miroslav Ćirković, and Vladica Simić (2017) The tench, Tinca tinca , is an endangered freshwater fish species in the Balkans. However, there are no management and conservation strategies developed for this species so far. In order to be able to develop such strategies, we first determined the phylogeographic identity of 70 tench individuals from four countries (Serbia, FYRO Macedonia, Hungary and Croatia) by PCR-RFLP analyses of two nuclear markers ( Act and RpS7 ) and one mitochondrial marker ( Cytb ). All makers enabled the identification of two major geographic clades of tench (Western and Eastern), while nuclear markers additionally enabled the identification of hybrids between the two clades. Based on the mitochondrial marker Cytb , tench populations can be separated into two distinct areas: areas north of the Danube River with the dominant Western origin, and areas south of the Danube River with the dominant Eastern origin. Data obtained for the Act gene demonstrated Eastern origin for most individuals (88.23%) while data obtained for the RpS7 gene demonstrated mixed origin with a high percentage of hybrids. The presence of high numbers of individuals with Western alleles for the RpS7 gene in areas south of the Danube may indicate a natural invasion of this phylogroup. According to these results, areas north and south of the Danube are identified as two main management units. Additionally, we identified the rare western haplotype W2 based on the Cytb marker which clearly indicated human-aided dispersals of tench in the investigated region and since some individuals with W2 origin were cultured, attention must be given to the genetic structure and identity of the introduced individuals, whether during introduction or reintroduction since biological and ecological consequences of the hybridization between the two major clades are still unknown. Finally, we propose and discuss management and conservation strategies for tench of both management areas.