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Lennart Balk - One of the best experts on this subject based on the ideXlab platform.
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biochemical biomarkers in adult female perch Perca fluviatilis in a chronically polluted gradient in the stockholm recipient sweden
Marine Pollution Bulletin, 2006Co-Authors: Tomas Hansson, Erik Noaksson, Doris Schiedek, Kari K Lehtonen, Pekka J Vuorinen, Birgitta Liewenborg, Ulla Tjarnlund, Marsha Hanson, Lennart BalkAbstract:By measuring a battery of basic physiological biomarkers and the concentration of SigmaDDT in adult female perch (Perca fluviatilis), an assumed aquatic pollution gradient was confirmed, with the city of Stockholm (Sweden) as a point source of anthropogenic substances. The investigation included an upstream gradient, westwards through Lake Malaren (46 km), and a downstream gradient, eastwards through the Stockholm archipelago (84 km). The results indicated a severe pollution situation in central Stockholm, with poor health status of the perch: retarded growth, increased frequency of sexually immature females, low gonadosomatic index, and disturbed visceral fat metabolism. SigmaDDT, measured as a pollution indicator, was 10-28 times higher than the background in perch from the Baltic Proper. Besides the main gradient other sources of pollution also influenced the response pattern of the measured biomarkers. In particular, there were strong indications of pollution coming from the Baltic Sea.
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reproductive status in female perch Perca fluviatilis outside a sewage treatment plant processing leachate from a refuse dump
Science of The Total Environment, 2005Co-Authors: Erik Noaksson, Maria Linderoth, Bodil Gustavsson, Yngve Zebuhr, Lennart BalkAbstract:Reproductive failure and endocrine disruption in female perch (Perca fluviatilis) and female brook trout (Salvelinus fontinalis), naturally exposed to toxic leachate from a municipal refuse dump, h ...
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dna adducts and histopathological lesions in perch Perca fluviatilis and northern pike esox lucius along a polycyclic aromatic hydrocarbon gradient on the swedish coastline of the baltic sea
Canadian Journal of Fisheries and Aquatic Sciences, 1998Co-Authors: G Ericson, Eric Lindesjoo, Lennart BalkAbstract:DNA adducts, histopathological abnormalities, and organosomatic indices were used to study contaminant effects on fish along a polycyclic aromatic hydrocarbon (PAH) gradient, leading away from an aluminum smelter on the Swedish Baltic coast. The level of DNA adducts, analysed using the 32P-postlabelling method, was at least 145 times higher in the liver of female perch (Perca fluviatilis) from the innermost site on the gradient, closest to the suspected point source of PAHs, than at a distant reference site. Of the DNA adducts analysed, a relatively small number accounted for a very high proportion of the total level of adducts (30-60% at the innermost site and close to 100% at the outermost site). These particular adducts could also be observed in extrahepatic tissues, such as trunk kidney and head kidney, along the entire gradient. Similar patterns of adducts were also observed in northern pike (Esox lucius). Focal hepatocellular degeneration in perch was about 15 times more extensive at the innermost s...
Bela Urbanyi - One of the best experts on this subject based on the ideXlab platform.
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development of sperm vitrification protocols for freshwater fish eurasian perch Perca fluviatilis and marine fish european eel anguilla anguilla
General and Comparative Endocrinology, 2017Co-Authors: Eszter Kasa, Gergely Bernath, Timea Kollar, Daniel żarski, Jelena Lujic, Zoran Marinovic, Zoltan Bokor, Arpad Hegyi, Bela UrbanyiAbstract:Vitrification was successfully applied to the sperm of two fish species, the freshwater Eurasian perch (Perca fluviatilis) and marine European eel (Anguilla anguilla). Sperm was collected, diluted in species-specific non-activating media and cryoprotectants and vitrified by plunging directly into liquid nitrogen without pre-cooling in its vapor. Progressive motility of fresh and vitrified-thawed sperm was evaluated with computer-assisted sperm analysis (CASA). Additional sperm quality parameters such as sperm head morphometry parameters (in case of European eel) and fertilizing capacity (in case of Eurasian perch) were carried out to test the effectiveness of vitrification. The vitrification method for Eurasian perch sperm resulting the highest post-thaw motility (14±1.6%) was as follows: 1:5 dilution ratio, Tanaka extender, 30% cryoprotectant (15% methanol+15% propylene-glycol), cooling device: Cryotop, 2μl droplets, and for European eel sperm: dilution ratio 1:1, with 40% cryoprotectant (20% MeOH and 20% PG), and 10% FBS, cooling device: Cryotop, with 2μl of sperm suspension. Viable embryos were produced by fertilization with vitrified Eurasian perch sperm (neurulation: 2.54±1.67%). According to the ASMA analysis, no significant decrease in head area and perimeter of vitrified European eel spermatozoa were found when compared to fresh spermatozoa.
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oocyte quality indicators in eurasian perch Perca fluviatilis l during reproduction under controlled conditions
Aquaculture, 2011Co-Authors: Daniel żarski, Katarzyna Targonska, Zoltan Bokor, Bela Urbanyi, Katarzyna Palinska, L Kotrik, Slawomir Krejszeff, Krzysztof Kupren, Akos Horvath, Dariusz KucharczykAbstract:Abstract This study examined embryo survival and viability of Eurasian perch, Perca fluviatilis L., larvae in relation to the fragmentation of oil droplets in ovulated oocytes. The study was conducted after controlled reproduction. Four (I–IV) categories of egg-ribbons quality were distinguished, based on the degree of oil droplet fragmentation (where at least one oil droplet with minimum 0.39 mm diameter were certified in all oocytes in egg-ribbon — categories I and II) and percentage of eggs with highly fragmented oil droplets (where diameter of oil droplets did not exceed 0.35 mm — categories III and IV) in the egg-ribbon. The dynamics of survival and some morphological parameters were investigated during embryonic and larval development up to 10 days post-hatch (DPH), under laboratory conditions. The laboratory-obtained results were compared to semi-commercial incubation and initial larval rearing. The fragmentation of oil droplets was accompanied by a decrease in egg quality. Oil droplets were found to coalesce after activation of eggs in water and during incubation process. Thus, the presented categorization may be used in non-activated eggs only. In both experiments, at 10 DPH the percentages of feeding larvae and those with an inflated swim bladder were recorded. The best results of laboratory-conducted incubation were obtained in category I and II (92.80 and 74.20% in the eyed-egg stage respectively). In category IV, the mortality rate of embryos exceeded 90%. The highest body deformation rate of freshly hatched larvae was observed in category III (67.86%) and IV (86.14%) that was related with fragmentation of oil droplets. These results were confirmed under semi-commercial conditions. The obtained results indicate that the proposed categorization may be a valuable tool for the quality evaluation of Eurasian perch egg-ribbons. It could be successfully applied in both commercial fish production and scientific activity.
Zoran Marinovic - One of the best experts on this subject based on the ideXlab platform.
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development of sperm vitrification protocols for freshwater fish eurasian perch Perca fluviatilis and marine fish european eel anguilla anguilla
General and Comparative Endocrinology, 2017Co-Authors: Eszter Kasa, Gergely Bernath, Timea Kollar, Daniel żarski, Jelena Lujic, Zoran Marinovic, Zoltan Bokor, Arpad Hegyi, Bela UrbanyiAbstract:Vitrification was successfully applied to the sperm of two fish species, the freshwater Eurasian perch (Perca fluviatilis) and marine European eel (Anguilla anguilla). Sperm was collected, diluted in species-specific non-activating media and cryoprotectants and vitrified by plunging directly into liquid nitrogen without pre-cooling in its vapor. Progressive motility of fresh and vitrified-thawed sperm was evaluated with computer-assisted sperm analysis (CASA). Additional sperm quality parameters such as sperm head morphometry parameters (in case of European eel) and fertilizing capacity (in case of Eurasian perch) were carried out to test the effectiveness of vitrification. The vitrification method for Eurasian perch sperm resulting the highest post-thaw motility (14±1.6%) was as follows: 1:5 dilution ratio, Tanaka extender, 30% cryoprotectant (15% methanol+15% propylene-glycol), cooling device: Cryotop, 2μl droplets, and for European eel sperm: dilution ratio 1:1, with 40% cryoprotectant (20% MeOH and 20% PG), and 10% FBS, cooling device: Cryotop, with 2μl of sperm suspension. Viable embryos were produced by fertilization with vitrified Eurasian perch sperm (neurulation: 2.54±1.67%). According to the ASMA analysis, no significant decrease in head area and perimeter of vitrified European eel spermatozoa were found when compared to fresh spermatozoa.
Daniel żarski - One of the best experts on this subject based on the ideXlab platform.
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development of sperm vitrification protocols for freshwater fish eurasian perch Perca fluviatilis and marine fish european eel anguilla anguilla
General and Comparative Endocrinology, 2017Co-Authors: Eszter Kasa, Gergely Bernath, Timea Kollar, Daniel żarski, Jelena Lujic, Zoran Marinovic, Zoltan Bokor, Arpad Hegyi, Bela UrbanyiAbstract:Vitrification was successfully applied to the sperm of two fish species, the freshwater Eurasian perch (Perca fluviatilis) and marine European eel (Anguilla anguilla). Sperm was collected, diluted in species-specific non-activating media and cryoprotectants and vitrified by plunging directly into liquid nitrogen without pre-cooling in its vapor. Progressive motility of fresh and vitrified-thawed sperm was evaluated with computer-assisted sperm analysis (CASA). Additional sperm quality parameters such as sperm head morphometry parameters (in case of European eel) and fertilizing capacity (in case of Eurasian perch) were carried out to test the effectiveness of vitrification. The vitrification method for Eurasian perch sperm resulting the highest post-thaw motility (14±1.6%) was as follows: 1:5 dilution ratio, Tanaka extender, 30% cryoprotectant (15% methanol+15% propylene-glycol), cooling device: Cryotop, 2μl droplets, and for European eel sperm: dilution ratio 1:1, with 40% cryoprotectant (20% MeOH and 20% PG), and 10% FBS, cooling device: Cryotop, with 2μl of sperm suspension. Viable embryos were produced by fertilization with vitrified Eurasian perch sperm (neurulation: 2.54±1.67%). According to the ASMA analysis, no significant decrease in head area and perimeter of vitrified European eel spermatozoa were found when compared to fresh spermatozoa.
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oocyte quality indicators in eurasian perch Perca fluviatilis l during reproduction under controlled conditions
Aquaculture, 2011Co-Authors: Daniel żarski, Katarzyna Targonska, Zoltan Bokor, Bela Urbanyi, Katarzyna Palinska, L Kotrik, Slawomir Krejszeff, Krzysztof Kupren, Akos Horvath, Dariusz KucharczykAbstract:Abstract This study examined embryo survival and viability of Eurasian perch, Perca fluviatilis L., larvae in relation to the fragmentation of oil droplets in ovulated oocytes. The study was conducted after controlled reproduction. Four (I–IV) categories of egg-ribbons quality were distinguished, based on the degree of oil droplet fragmentation (where at least one oil droplet with minimum 0.39 mm diameter were certified in all oocytes in egg-ribbon — categories I and II) and percentage of eggs with highly fragmented oil droplets (where diameter of oil droplets did not exceed 0.35 mm — categories III and IV) in the egg-ribbon. The dynamics of survival and some morphological parameters were investigated during embryonic and larval development up to 10 days post-hatch (DPH), under laboratory conditions. The laboratory-obtained results were compared to semi-commercial incubation and initial larval rearing. The fragmentation of oil droplets was accompanied by a decrease in egg quality. Oil droplets were found to coalesce after activation of eggs in water and during incubation process. Thus, the presented categorization may be used in non-activated eggs only. In both experiments, at 10 DPH the percentages of feeding larvae and those with an inflated swim bladder were recorded. The best results of laboratory-conducted incubation were obtained in category I and II (92.80 and 74.20% in the eyed-egg stage respectively). In category IV, the mortality rate of embryos exceeded 90%. The highest body deformation rate of freshly hatched larvae was observed in category III (67.86%) and IV (86.14%) that was related with fragmentation of oil droplets. These results were confirmed under semi-commercial conditions. The obtained results indicate that the proposed categorization may be a valuable tool for the quality evaluation of Eurasian perch egg-ribbons. It could be successfully applied in both commercial fish production and scientific activity.
Zoltan Bokor - One of the best experts on this subject based on the ideXlab platform.
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development of sperm vitrification protocols for freshwater fish eurasian perch Perca fluviatilis and marine fish european eel anguilla anguilla
General and Comparative Endocrinology, 2017Co-Authors: Eszter Kasa, Gergely Bernath, Timea Kollar, Daniel żarski, Jelena Lujic, Zoran Marinovic, Zoltan Bokor, Arpad Hegyi, Bela UrbanyiAbstract:Vitrification was successfully applied to the sperm of two fish species, the freshwater Eurasian perch (Perca fluviatilis) and marine European eel (Anguilla anguilla). Sperm was collected, diluted in species-specific non-activating media and cryoprotectants and vitrified by plunging directly into liquid nitrogen without pre-cooling in its vapor. Progressive motility of fresh and vitrified-thawed sperm was evaluated with computer-assisted sperm analysis (CASA). Additional sperm quality parameters such as sperm head morphometry parameters (in case of European eel) and fertilizing capacity (in case of Eurasian perch) were carried out to test the effectiveness of vitrification. The vitrification method for Eurasian perch sperm resulting the highest post-thaw motility (14±1.6%) was as follows: 1:5 dilution ratio, Tanaka extender, 30% cryoprotectant (15% methanol+15% propylene-glycol), cooling device: Cryotop, 2μl droplets, and for European eel sperm: dilution ratio 1:1, with 40% cryoprotectant (20% MeOH and 20% PG), and 10% FBS, cooling device: Cryotop, with 2μl of sperm suspension. Viable embryos were produced by fertilization with vitrified Eurasian perch sperm (neurulation: 2.54±1.67%). According to the ASMA analysis, no significant decrease in head area and perimeter of vitrified European eel spermatozoa were found when compared to fresh spermatozoa.
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oocyte quality indicators in eurasian perch Perca fluviatilis l during reproduction under controlled conditions
Aquaculture, 2011Co-Authors: Daniel żarski, Katarzyna Targonska, Zoltan Bokor, Bela Urbanyi, Katarzyna Palinska, L Kotrik, Slawomir Krejszeff, Krzysztof Kupren, Akos Horvath, Dariusz KucharczykAbstract:Abstract This study examined embryo survival and viability of Eurasian perch, Perca fluviatilis L., larvae in relation to the fragmentation of oil droplets in ovulated oocytes. The study was conducted after controlled reproduction. Four (I–IV) categories of egg-ribbons quality were distinguished, based on the degree of oil droplet fragmentation (where at least one oil droplet with minimum 0.39 mm diameter were certified in all oocytes in egg-ribbon — categories I and II) and percentage of eggs with highly fragmented oil droplets (where diameter of oil droplets did not exceed 0.35 mm — categories III and IV) in the egg-ribbon. The dynamics of survival and some morphological parameters were investigated during embryonic and larval development up to 10 days post-hatch (DPH), under laboratory conditions. The laboratory-obtained results were compared to semi-commercial incubation and initial larval rearing. The fragmentation of oil droplets was accompanied by a decrease in egg quality. Oil droplets were found to coalesce after activation of eggs in water and during incubation process. Thus, the presented categorization may be used in non-activated eggs only. In both experiments, at 10 DPH the percentages of feeding larvae and those with an inflated swim bladder were recorded. The best results of laboratory-conducted incubation were obtained in category I and II (92.80 and 74.20% in the eyed-egg stage respectively). In category IV, the mortality rate of embryos exceeded 90%. The highest body deformation rate of freshly hatched larvae was observed in category III (67.86%) and IV (86.14%) that was related with fragmentation of oil droplets. These results were confirmed under semi-commercial conditions. The obtained results indicate that the proposed categorization may be a valuable tool for the quality evaluation of Eurasian perch egg-ribbons. It could be successfully applied in both commercial fish production and scientific activity.