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EN
Proper multidimensional management of perch, common and one of the most abundant species in European freshwaters, is a challenge both from ecological and commercial perspective. However, all activity relating to the management of the perch must be based on good genetic knowledge in order to ensure a purity of species and further conservation of biodiversity. Therefore, in the present study, the mtDNA cytb and D–loop restriction analysis was applied in order to estimate genetic diversity within and among three perch (Perca fluviatilis L.) populations in reservoirs of Central Poland: Sulejów, Próba and Jeziorsko. Two out of nine, and two out of eight restriction enzymes were polymorphic for cytb and D–loop, respectively. Five different haplotypes were detected with the simultaneous occurrence of haplotype 1 in all three populations. Nucleotide diversity values within investigated populations were low (0.003 to 0.02). No significant differentiation (P = 0.248) among populations representing two different catchments of Pilica and Vistula rivers, was observed. The lack of genetic differentiation of perch populations is the first important element for the development of a strategy to regulate the perch in Polish river systems, with simultaneous reduction of fish in eutrophic reservoirs and increase in amount of perch, in sites favorable for fishing and aquaculture.
EN
Aeromonas hydrophila is a valuable indicator of the quality of water polluted by sewage and pathogens that pose a risk for humans and cold-blooded animals, including fi sh. The main aim of this research was to evaluate anthropogenic pollution of river water based on genetic diversity of 82 A. hydrophila strains by means of RAPD, semi-random AP-PCR (ISJ) and the rep-BOX conservative repeats test. Genetic diversity of A. hydrophila was HT = 0.28 (SD = 0.02) for all DNA markers (RAPD, semi random and rep-BOX). None of the analyzed electrophoretic patterns was identical, implying that there were many sources of strain transmission. The presence of genes for aerolysin (aerA), hemolysin (ahh1) and the cytotoxic enzyme complex (AHCYTOGEN) was verifi ed for all tested strains, and drug resistance patterns for tetracycline, enrofl oxacin and erythromycin were determined. The most diverse A. hydrophila strains isolated from river water were susceptible to enrofl oxacine (HS = 0.27), whereas less diverse strains were susceptible to erythromycin (HS = 0.24). The presence of the multidrug resistance marker (ISJ4-25; 1100 bp locus) in the examined strains (resistant to three analyzed drugs) indicates that intensive fi sh cultivation affects the microbiological quality of river water.
PL
Aeromonas hydrophila jest cennym wskaźnikiem jakości wody w przypadku zanieczyszczeń ściekami oraz mikroorganizmami względnie patogennymi dla człowieka i zwierząt zimnokrwistych, w tym ryb. Celem niniejszych badań była ocena zanieczyszczenia antropogenicznego na podstawie zróżnicowania genetycznego 82 szczepów A. hydrophila poprzez analizy RAPD, pół-przypadkowo amplifi kowanej klasy AP-PCR (ISJ) i konserwatywnego powtórzenia rep-BOX. Zróżnicowanie genetyczne A. hydrophila wyniosło HT = 0,28 (SD = 0,02) dla wszystkich markerów DNA (RAPD, pół-przypadkowe i rep-BOX). Wszystkie szczepy dla wszystkich markerów ujawniły indywidualny wzór elektroforetyczny, nie ujawniono jednego źródła rozprzestrzeniania się szczepów. U szczepów potwierdzono obecność genów aerolizyny (aerA), hemolizyny (ahh1) i kompleksu enzymów cytotoksycznych (AHCYTOGEN), jak również określono wzorzec oporności na tetracyklinę, enrofl oksacynę i erytromycynę. Najbardziej zróżnicowane okazały się szczepy A. hydrophila wrażliwe na enrofl oksacynę (HS = 0,27) a najmniej zróżnicowane były szczepy wrażliwe na erytromycynę (HS = 0,24). Wyselekcjonowany marker wielolekooporności (locus ISJ4-25, 1100 pz) obecny u szczepów (opornych na 3 rozpatrywane leki) świadczy o wpływie intensywnej hodowli ryb na jakość mikrobiologiczną wody rzecznej.
EN
Kozlov's pika is a rare and endangered lagomorph species with a limited distribution in the southern Kunlun Mountains in western China. Because of its endangered status, Kozlov's pika is considered a priority species for research and conservation action. Genetic variation and molecular evolution of the Kozlov's pika were studied based on a total of 14 individuals from four locations along the eastern boundary between Xinjiang and Tibet province (35.20-36.48[degrees]N, 86.08-83.04[degrees]E) on extremely high elevation (usually over 4800 m a.s.l.). The density of local populations was about 3-4 per ha, living in a typical alpine desert grassland habitat. The complete mitochondrial cytochrome b (cytb) gene was amplified and sequenced. Based on the cytb gene sequences the genetic variation and molecular evolution were analyzed. Unexpected high haplotype diversity (0.956 [plus or minus] 0.045) but low nucleotide diversity (0.00537 [plus or minus] 0.00126) was found, indicating past demographic expansion. Significant partitioning of variance (P <0.01) among populations (46.7%), and within populations (53.3%), indicating low level of genetic differentiations among local populations. Our results gave an optimistic survival status of Kozlov's pika at the genetic level. Bayes Empirical Bayes analysis with model M2a and M8 detected three positively selected amino acid sites at the significance level of 0.05. The mutant types with either or both of the mutations aspartic acid to asparagine and glutamic acid to lysine had higher isoelectric point values. We suggested these mutant types might have biological significance to help individuals to adapt to the extremely high elevation habitats.
EN
The pike-perch is one of the main commercial fish species in Uzbekistan. Historically, it inhabited the Aral Sea and deltas of inflowing rivers (Amu-Darya and Syr-Darya). At the beginning of the 1960s it was introduced into water bodies of the middle Amu-Darya and Syr-Darya from the Ural River. The present study was aimed to evaluate the current genetic status of wild pike-perch populations from different water bodies using nine recently isolated species-specific microsatellite markers. The three examined Uzbek pike-perch populations expressed significantly higher average numbers of alleles per locus (5.56 to 14.22) than three year-classes of a German wild population (3.11 to 3.78) included for comparison. On the other hand, average observed and expected heterozygosities were not significantly different in both regions (0.743 and 0.760 in Uzbek pike-perch; 0.576 and 0.471 in German pike-perch). After sequential Bonferroni corrections all Uzbek populations were found to be in Hardy-Weinberg equilibrium. Genetic differentiation between all populations as estimated by FST values was statistically significant. Pike-perch from Amu-Darya River delta and Tudakul reservoir were less differentiated from each other probably due to gene flow between them (both water bodies are connected) whereas the more distinct Syr-Darya River population showed indication for introgression with non-native individuals stocked in that region. Since stocking is widely practiced to satisfy the growing demand of pike-perch fisheries in Uzbekistan, fish seed for such activities should be obtained from local, genetically undisturbed populations such as the Amu-Darya River delta population.
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