Wyniki wyszukiwania - BazTech

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Możliwości rozrodu ryb łososiowatych w rzece Wołczenicy

Tański A., Jankowski M., Sosnowski W., Brysiewicz A.

Woda-Środowisko-Obszary Wiejskie

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2018

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T. 18, z. 4

29--40

PL

Wędrowne ryby łososiowate są niezwykle cenne z gospodarczego punktu widzenia, a ich występowanie w rzece potwierdza dobrą jakość warunków środowiskowych. Łosoś (Salmo salar L.) i troć wędrowna (Salmo trutta m. trutta L.) do rozrodu wymagają odpowiedniego żwirowo-kamienistego substratu, w którym budują gniazda – kopce tarłowe. Kopce tarłowe ryb szczegółowo opisano, podając ich rozmiary i lokalizację GPS. Wyniki porównano z uzyskanymi w badaniach przeprowadzonych w ubiegłych latach na tym odcinku oraz z obserwacjami przeprowadzonymi na innych ciekach. W wyniku prowadzonych prac melioracyjnych w wielu ciekach dokonano regulacji koryt rzecznych i pogłębiono je, eliminując podłoża żwirowo-kamieniste. Ponadto istotnym elementem ograniczającym zasięg występowania wędrownych ryb jest zabudowa hydrotechniczna. Podczas badań przeanalizowano możliwość rozrodu ryb w Wołczenicy oraz zewidencjonowano tarliska w dwóch sezonach rozrodczych – 2016–2017 i 2017–2018. Wyniki wskazują na istotne zmniejszenie liczby gniazd w porównaniu z wcześniej prowadzonymi badaniami – z dwunastu do trzech.

EN

From ecological point of view migratory salmonid fish are extremely valuable, their presence in a river confirms a good quality of the environmental conditions. Both atlantic salmon (Salmo salar L.) and sea trout (Salmo trutta m. trutta L.) require gravel substrate to build their spawning nests. As a result of drainage works and river bed maintenance many riverbeds have been changed and regulated, their gravel substrate dug removed in order to deepen the bed. First of all hydraulic constructions are very important factors limiting the spatial distribution of migratory fish in rivers. During the studies possibility of natural reproduction of salmonids in the Wołczenica River was analysed by records of spawning nests in two following spawning seasons 2016–2017 and 2017–2018. The results show significant decrease in spawning nests number comparing to similar survey conducted a decade ago.

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Zmiany rozmieszczenia gniazd tarłowych troci wędrownej (Salmo trutta m. trutta L.) pod wpływem działalności człowieka na przykładzie rzeki Gowienicy

Brysiewicz A., Jankowski M., Tański A., Krzystolik J.

Woda-Środowisko-Obszary Wiejskie

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2017

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T. 17, z. 3

41--53

PL

W pracy przedstawiono wyniki ewidencji gniazd tarłowych troci wędrownej (Salmo trutta m. trutta L.) w sezonie badawczym 2016–2017 w rzece Gowienicy (woj. zachodniopomorskie). Odcinek objęty badaniami obejmował fragment cieku od jego ujścia do Zalewu Szczecińskiego aż do progu piętrzącego znajdującego się w pobliżu miejscowości Łoźnica, przez który ryby nie są w stanie przepłynąć w górę rzeki. Kopce tarłowe ryb szczegółowo opisano, podając ich rozmiary i lokalizację GPS. Wyniki porównano z uzyskanymi w badaniach przeprowadzonych w ubiegłych latach na tym odcinku oraz z obserwacjami przeprowadzonymi na innych ciekach. Wykazano postępujące zmiany jakościowe i ilościowe kopców tarłowych i terenów tarłowych w poszczególnych sezonach w Gowienicy oraz w porównaniu z innymi ciekami. Za najważniejszą przyczynę malejącej liczby tarlisk oraz terenów tarłowych uznano działalność człowieka.

EN

The paper presents results of spawning nests of migratory trout during 2016–2017 research season in the Gowienica River (West Pomeranian Voivodeship). The section covered by the study included a section of the stream from its estuary to the Szczecin Lagoon up to the damping threshold near Łoźnica, through which the fish were unable to swim upstream. Spawning fishes are described in detail, including their size and GPS location. The results were compared with previous studies in this section and with other studies. Progressive qualitative and quantitative changes have been demonstrated between seasons in Gowienica River and in comparison with other waterways. Human activity was considered the most important cause of the decreasing number of spawning grounds and spawning areas.

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Pasożyty jelitowe młodocianych ryb łososiowatych zlewni dolnej Odry i środkowego Niemna

Pilecka-Rapacz M., Kazlauskiene N., Kesminas V, Czerniawski R.

Rocznik Ochrona Środowiska

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2013

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Tom 15, cz. 1

671--682

EN

Atlantic salmon died out in Poland during the 1980s. The current population was recreated with Latvian salmon and now forms part of the southern Baltic cohort. Polish sea trout and brown trout come from the home cohort, but have survived only with regular restocking. In Lithuania, all the salmonides are from the home cohort and have not been restocked. The aim of this study was to compare parasitic invasion in juvenile salmonides that come from Poland and Lithuania. The juvenile salmonides in this study came from the lower Oder River basin and from the middle of the Neman River. 153 fish were caught using electrofishing from 2004 to 2006. The salmonides in the Oder had been artificially restocked and those in the Neman were wild. 33 salmon, 58 sea trout and 24 brown trout came from small tributaries of the Oder; 22 salmon, 5 sea trout and 11 brown trout came from tributaries of the middle Neman River. The fish were either 0+, 1+, or 2+ years old. Their size was characteristic for their species at that age, which suggested that they were in good condition. Our examination found 6 species of parasites from 3 taxa: Cestoda – Cyathocephalus truncates; Nematoda – Cystidicoloides ephe¬meridarum and Raphidascaris acus; and Acanthocephala – Acantho¬cephalus lucii, A. anguillae and Metechinorhynchus truttae. We found all three taxa of parasites in all the salmonides that came from the tributaries of the Oder, but all three taxa were found only in salmon from the Neman tributaries. In sea trout and brown trout from tributaries of the Nemen River we found only Nematoda. The invasion frequency was much higher in salmonides that came from tributaries of the Oder River than in salmonides from tributaries of the Nemen River. In tributaries of the Oder River, 57.6% of the salmon, 62.1% of the sea trout, and 58.3% of the brown trout had parasites. In tributaries of the Nemen River, 27.3% of the salmon, 40% of the sea trout, and 36.4% of the brown trout had parasites. In salmonides from both rivers the most common parasites were C. ephemeridarum, M. truttae, and C. truncatus. The other species of parasites were found in very few cases. Older salmonides had greater numbers of parasites. Although the salmonides came from different rivers and had different origins, the species of parasites that they had were typical for their family. In conclusion, parasite invasion is similar in salmonides both from the lower Oder River basin and from the middle of the Neman River.

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Cytologic ploidy determination in fish - an example of two salmonid species

Jankun M., Kuzminski H., Furgala-Selezniow G.

Environmental Biotechnology

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2007

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Vol. 3, No. 2

52-56

EN

The method of ploidy level determination depends on the equipment, expertise of the lab or farm staff, and on the material studied (fish species, specimens' age and size, etc.). The combination of some simple techniques can be very helpful for fast, reliable and inexpensive assessment of effects of genome manipulations. Among indirect methods the nucleoli quantification seems to be the most convenient one, except that it is limited to species possessing one locus of nucleolar organizer regions (NORs) (rainbow trout as an example). Species with multilocus NORs (like brook trout) need another method, for instance sizing of erythrocytes nuclei. These techniques can be useful for identification of products resulting from new approaches in biotechnology applied to fish culture, as polyploidisation or hybridisation, for characteristics of transformation levels of organisms found in the wild or those produced due to experimental treatments.