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Harald Niederstatter - One of the best experts on this subject based on the ideXlab platform.
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Contrasting effects of temperature acclimation on mechanisms of ionic regulation in a eurythermic and a stenothermic species of freshwater fish (Rutilus Rutilus and salvelinus alpinus)
Comparative Biochemistry and Physiology Part A: Physiology, 1991Co-Authors: Pablo J. Schwarzbaum, Wolfgang Wieser, Harald NiederstatterAbstract:Abstract 1. 1. Effects of temperature on aspects of ionic regulation in kidney and gills of Rutilus Rutilus and Salvelinus alpinus were studied by a variety of techniques. 2. 2. In the kidney tissue of cold acclimated R. Rutilus, the maximal number of binding sites per mg protein (Bmax) and the activity of Na+, K+-ATPase, as well as tissue respiration increased significantly, whereas in S. alpinus no changes in these variables were observed. On the other hand, 86Rb+ efflux from kidney tissue was unaffected by temperature in R. Rutilus, whereas it was about 60% lower in 5. alpinus acclimated and measured at 5°C, than in specimens acclimated and measured at 15°C. 3. 3. In both species, the activity of gill Na+, K+-ATPase was 1.5- to 2-fold higher in cold-acclimated than in warm-acclimated fish although Bmax decreased in R. Rutilus, but remained constant in S. alpinus. 4. 4. Problems of ionic regulation are discussed with regard to differences in temperature sensitivity of passive flows and primary active transport of ions in the tissues of poikilothermic animals.
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Contrasting effects of temperature acclimation on mechanisms of ionic regulation in a eurythermic and a stenothermic species of freshwater fish (Rutilus Rutilus and salvelinus alpinus)
Comparative Biochemistry and Physiology Part A: Physiology, 1991Co-Authors: Pablo J. Schwarzbaum, Wolfgang Wieser, Harald NiederstatterAbstract:Abstract 1. 1. Effects of temperature on aspects of ionic regulation in kidney and gills of Rutilus Rutilus and Salvelinus alpinus were studied by a variety of techniques. 2. 2. In the kidney tissue of cold acclimated R. Rutilus, the maximal number of binding sites per mg protein (Bmax) and the activity of Na+, K+-ATPase, as well as tissue respiration increased significantly, whereas in S. alpinus no changes in these variables were observed. On the other hand, 86Rb+ efflux from kidney tissue was unaffected by temperature in R. Rutilus, whereas it was about 60% lower in 5. alpinus acclimated and measured at 5°C, than in specimens acclimated and measured at 15°C. 3. 3. In both species, the activity of gill Na+, K+-ATPase was 1.5- to 2-fold higher in cold-acclimated than in warm-acclimated fish although Bmax decreased in R. Rutilus, but remained constant in S. alpinus. 4. 4. Problems of ionic regulation are discussed with regard to differences in temperature sensitivity of passive flows and primary active transport of ions in the tissues of poikilothermic animals.
Pablo J. Schwarzbaum - One of the best experts on this subject based on the ideXlab platform.
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Contrasting effects of temperature acclimation on mechanisms of ionic regulation in a eurythermic and a stenothermic species of freshwater fish (Rutilus Rutilus and salvelinus alpinus)
Comparative Biochemistry and Physiology Part A: Physiology, 1991Co-Authors: Pablo J. Schwarzbaum, Wolfgang Wieser, Harald NiederstatterAbstract:Abstract 1. 1. Effects of temperature on aspects of ionic regulation in kidney and gills of Rutilus Rutilus and Salvelinus alpinus were studied by a variety of techniques. 2. 2. In the kidney tissue of cold acclimated R. Rutilus, the maximal number of binding sites per mg protein (Bmax) and the activity of Na+, K+-ATPase, as well as tissue respiration increased significantly, whereas in S. alpinus no changes in these variables were observed. On the other hand, 86Rb+ efflux from kidney tissue was unaffected by temperature in R. Rutilus, whereas it was about 60% lower in 5. alpinus acclimated and measured at 5°C, than in specimens acclimated and measured at 15°C. 3. 3. In both species, the activity of gill Na+, K+-ATPase was 1.5- to 2-fold higher in cold-acclimated than in warm-acclimated fish although Bmax decreased in R. Rutilus, but remained constant in S. alpinus. 4. 4. Problems of ionic regulation are discussed with regard to differences in temperature sensitivity of passive flows and primary active transport of ions in the tissues of poikilothermic animals.
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Contrasting effects of temperature acclimation on mechanisms of ionic regulation in a eurythermic and a stenothermic species of freshwater fish (Rutilus Rutilus and salvelinus alpinus)
Comparative Biochemistry and Physiology Part A: Physiology, 1991Co-Authors: Pablo J. Schwarzbaum, Wolfgang Wieser, Harald NiederstatterAbstract:Abstract 1. 1. Effects of temperature on aspects of ionic regulation in kidney and gills of Rutilus Rutilus and Salvelinus alpinus were studied by a variety of techniques. 2. 2. In the kidney tissue of cold acclimated R. Rutilus, the maximal number of binding sites per mg protein (Bmax) and the activity of Na+, K+-ATPase, as well as tissue respiration increased significantly, whereas in S. alpinus no changes in these variables were observed. On the other hand, 86Rb+ efflux from kidney tissue was unaffected by temperature in R. Rutilus, whereas it was about 60% lower in 5. alpinus acclimated and measured at 5°C, than in specimens acclimated and measured at 15°C. 3. 3. In both species, the activity of gill Na+, K+-ATPase was 1.5- to 2-fold higher in cold-acclimated than in warm-acclimated fish although Bmax decreased in R. Rutilus, but remained constant in S. alpinus. 4. 4. Problems of ionic regulation are discussed with regard to differences in temperature sensitivity of passive flows and primary active transport of ions in the tissues of poikilothermic animals.
Jukka Horppila - One of the best experts on this subject based on the ideXlab platform.
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Bridge under troubled water: Turbulence and niche partitioning in fish foraging.
Ecology and Evolution, 2016Co-Authors: Zeynep Pekcan-hekim, Noora Hellén, Laura Härkönen, Per Anders Nilsson, Leena Nurminen, Jukka HorppilaAbstract:The coexistence of competing species relies on niche partitioning. Competitive exclusion is likely inevitable at high niche overlap, but such divide between competitors may be bridged if environmental circumstances displace competitor niches to enhance partitioning. Foraging-niche dimension can be influenced by environmental characteristics, and if competitors react differently to such conditions, coexistence can be facilitated. We here experimentally approach the partitioning effects of environmental conditions by evaluating the influence of water turbulence on foraging-niche responses in two competing fish species, Eurasian perch Perca fluviatilis and roach Rutilus Rutilus, selecting from planktonic and benthic prey. In the absence of turbulence, both fish species showed high selectivity for benthic chironomid larvae. R. Rutilus fed almost exclusively on zoobenthos, whereas P. fluviatilis complemented the benthic diet with zooplankton (mainly copepods). In turbulent water, on the other hand, the foraging-niche widths of both R. Rutilus and P. fluviatilis increased, while their diet overlap simultaneously decreased, caused by 20% of the R. Rutilus individuals turning to planktonic (mainly bosminids) prey, and by P. fluviatilis increasing foraging on littoral/benthic food sources. We show that moderate physical disturbance of environments, such as turbulence, can enhance niche partitioning and thereby coexistence of competing foragers. Turbulence affects prey but not fish swimming capacities, with consequences for prey-specific distributions and encounter rates with fish of different foraging strategies (pause-travel P. fluviatilis and cruise R. Rutilus). Water turbulence and prey community structure should hereby affect competitive interaction strengths among fish species, with consequences for coexistence probability as well as community and system compositions.
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diet shifts and food selection of perch perca fluviatilis and roach Rutilus Rutilus in humic lakes of varying water colour
Journal of Fish Biology, 2010Co-Authors: Satu Estlander, Mika Vinni, Mikko Olin, Jukka Horppila, Jukka Ruuhijärvi, Martti Rask, Leena Nurminen, S Immonen, Hannu LehtonenAbstract:The field data from four humic lakes suggested that water colour may have both direct and indirect effects on inter- and intra-specific interactions of perch Perca fluviatilis and roach Rutilus Rutilus. The results agree with suggestions that, compared with R. Rutilus, P. fluviatilis may be an inferior forager on zooplankton in highly coloured water. As an indirect effect, water colour decreases the coverage of macrophytes and limits suitable littoral habitats, benefiting R. Rutilus over P. fluviatilis. Perca fluviatilis benefiting from complex habitats does not have the advantage in macrophyte-poor highly coloured water.
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feeding efficiency of planktivorous perch perca fluviatilis and roach Rutilus Rutilus in varying turbidity an individual based approach
Journal of Fish Biology, 2010Co-Authors: Leena Nurminen, Zeynep Pekcanhekim, Jukka HorppilaAbstract:The feeding rate of perch Perca fluviatilis showed high individual variation at low and moderate turbidities, when one individual had consumed more Daphnia pulex than any other fish, whereas no such variation in feeding efficiency was observed with roach Rutilus Rutilus. There was a significant decrease in total consumption of D. pulex by P. fluviatilis with increasing turbidity, but no correlation was observed in the case of R. Rutilus. The results suggest that the difference in the ontogeny of P. fluviatilis and R. Rutilus may be detectable as behaviour-related species-specific trait differences in the early planktivorous feeding stage of the two common species.
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Feeding efficiency of planktivorous perch Perca fluviatilis and roach Rutilus Rutilus in varying turbidity: an individual‐based approach
Journal of Fish Biology, 2010Co-Authors: Leena Nurminen, Zeynep Pekcan-hekim, Jukka HorppilaAbstract:The feeding rate of perch Perca fluviatilis showed high individual variation at low and moderate turbidities, when one individual had consumed more Daphnia pulex than any other fish, whereas no such variation in feeding efficiency was observed with roach Rutilus Rutilus. There was a significant decrease in total consumption of D. pulex by P. fluviatilis with increasing turbidity, but no correlation was observed in the case of R. Rutilus. The results suggest that the difference in the ontogeny of P. fluviatilis and R. Rutilus may be detectable as behaviour-related species-specific trait differences in the early planktivorous feeding stage of the two common species.
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Seasonal changes in the diets and relative abundances of perch and roach in the littoral and pelagic zones of a large lake
Journal of Fish Biology, 2000Co-Authors: Jukka Horppila, Jukka Ruuhijärvi, Martti Rask, C. Karppinen, Kari Nyberg, Mikko OlinAbstract:In the Enonselka and Laitialanselka basins of Lake Vesijarvi, perch Perca fluviatilis and roach Rutilus Rutilus were abundant in the littoral and in the pelagic zones throughout the summer. In the littoral zone, roach was always more numerous than perch, while perch dominated in the open water. Intraspecific diet overlap values were higher than interspecific values. In the pelagic zone, perch
Marketa Ondrackova - One of the best experts on this subject based on the ideXlab platform.
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seasonal dynamics of posthodiplostomum cuticola digenea diplostomatidae metacercariae and parasite enhanced growth of juvenile host fish
Parasitology Research, 2004Co-Authors: Marketa Ondrackova, Martin Reichard, Pavel Jurajda, Milan GelnarAbstract:The seasonal dynamics of Posthodiplostomum cuticola metacercariae in 0+ juvenile fish, Rutilus Rutilus, Scardinius erythrophthalmus and Abramis bjoerkna, was studied on the floodplain of the Dyje River, Czech Republic. Prevalence and mean abundance of P. cuticola were significantly higher in R. Rutilus than in S. erythrophthalmus or A. bjoerkna. A seasonal pattern of parasite infection with maximum values in autumn was evident in all three species. No effect of overwintering on the P. cuticola infection was detected. Parasite-induced growth was found for all three fish species investigated; the fish standard length and body weight of parasitized individuals were significantly higher than those of unparasitized fish from July to October. In April, no difference was found. The maximum enhanced growth of parasitized fish was found in months with low zooplankton densities, while the difference was lower when food was abundant.
Wolfgang Wieser - One of the best experts on this subject based on the ideXlab platform.
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Contrasting effects of temperature acclimation on mechanisms of ionic regulation in a eurythermic and a stenothermic species of freshwater fish (Rutilus Rutilus and salvelinus alpinus)
Comparative Biochemistry and Physiology Part A: Physiology, 1991Co-Authors: Pablo J. Schwarzbaum, Wolfgang Wieser, Harald NiederstatterAbstract:Abstract 1. 1. Effects of temperature on aspects of ionic regulation in kidney and gills of Rutilus Rutilus and Salvelinus alpinus were studied by a variety of techniques. 2. 2. In the kidney tissue of cold acclimated R. Rutilus, the maximal number of binding sites per mg protein (Bmax) and the activity of Na+, K+-ATPase, as well as tissue respiration increased significantly, whereas in S. alpinus no changes in these variables were observed. On the other hand, 86Rb+ efflux from kidney tissue was unaffected by temperature in R. Rutilus, whereas it was about 60% lower in 5. alpinus acclimated and measured at 5°C, than in specimens acclimated and measured at 15°C. 3. 3. In both species, the activity of gill Na+, K+-ATPase was 1.5- to 2-fold higher in cold-acclimated than in warm-acclimated fish although Bmax decreased in R. Rutilus, but remained constant in S. alpinus. 4. 4. Problems of ionic regulation are discussed with regard to differences in temperature sensitivity of passive flows and primary active transport of ions in the tissues of poikilothermic animals.
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Contrasting effects of temperature acclimation on mechanisms of ionic regulation in a eurythermic and a stenothermic species of freshwater fish (Rutilus Rutilus and salvelinus alpinus)
Comparative Biochemistry and Physiology Part A: Physiology, 1991Co-Authors: Pablo J. Schwarzbaum, Wolfgang Wieser, Harald NiederstatterAbstract:Abstract 1. 1. Effects of temperature on aspects of ionic regulation in kidney and gills of Rutilus Rutilus and Salvelinus alpinus were studied by a variety of techniques. 2. 2. In the kidney tissue of cold acclimated R. Rutilus, the maximal number of binding sites per mg protein (Bmax) and the activity of Na+, K+-ATPase, as well as tissue respiration increased significantly, whereas in S. alpinus no changes in these variables were observed. On the other hand, 86Rb+ efflux from kidney tissue was unaffected by temperature in R. Rutilus, whereas it was about 60% lower in 5. alpinus acclimated and measured at 5°C, than in specimens acclimated and measured at 15°C. 3. 3. In both species, the activity of gill Na+, K+-ATPase was 1.5- to 2-fold higher in cold-acclimated than in warm-acclimated fish although Bmax decreased in R. Rutilus, but remained constant in S. alpinus. 4. 4. Problems of ionic regulation are discussed with regard to differences in temperature sensitivity of passive flows and primary active transport of ions in the tissues of poikilothermic animals.
