In a small, 12 ha, mesotropic lake, roach Rutilus rutilus performed diel habitat shifts that clearly influenced the composition of their diet. During daytime, roach stayed in the littoral zone and concentrated on littoral prey. At night they were found in the pelagic zone, and pelagic prey items such as Daphnia spp. or Chaoborus flavicans dominated their food. On a seasonal scale, there were sh...

The complementary DNAs (cDNA) encoding the [Trp7,Leu8]-gonadotrophin-releasing hormone (salmon-type GnRH; sGnRH:GeneBank accession no. u60667) and the [His5,Trp7,Tyr8]-GnRH (chicken-II-type GnRH; cGnRH-II: GeneBank accession no. u60668) precursor in the roach (Rutilus rutilus) were isolated and sequenced following reverse transcription and rapid amplification of cDNA ends (RACE). The sGnRH and ...

The ichthyological biodiversity of Polish lakes is poorly understood, even in not used for fishing and those under strict protection. With this mind, the aim study was to conduct a comprehensive survey several Wolin National Park (Poland). conducted Domysławskie Gardno anthropogenic Stara Kredownia reservoir. Each exercise using benthic nets over 12 h period. fish caught were measured weighed, ...

Experiments were conducted to assess the pathogenicity of 2 'atypical' Aerornonas salmon~cida strains solated from ulcerated flounders Platichthys flesus for this species, rainbow trout Oncorhynchus mykiss, roach Rutilus rutilus, and bleak Alburnus alburnus. The pathogenicity of the strains was evaluated by 3 challenge methods: intraperitonea] (i-p.) injection, subdermal (S d . ) injection, and...

Several hypotheses concerning the dominance of percids under mesotrophic lake conditions were tested in five lakes of intermediate trophic state, situated in northeastern Germany. In contrast to prediction, the fish communities in four lakes were dominated by cyprinids (roach, Rutilus rutilus and bream, Abramis brama), while percids (Eurasian perch, Percafluviatilis) dominated in one lake only....

Fish communities differ significantly between the littoral and pelagic habitats. This paper attempts to define shift in two habitats based on European standard gillnet catch. We sampled benthic from shore Lake Most Římov Reservoir (Czech Republic). The 3 m deep nets were spanned across water body at equal distances boundary points, where depth was 3.5 m. community contained more fish, species, ...

By combining morphology, ecology, biology, and biogeography with the available molecular (sequence variation of the entire mitochondrial cytochrome b gene; cyt-b) and karyology data, the taxonomy of several species of the Rutilus complex inhabiting southern Europe is revised. Rutilus stoumboudae, new species, is described from Lake Volvi, Greece. It differs from Rutilus rutilus in possessing mo...