Description: Das Projekt "Hormonale Steuerung des Fischwachstums unter verschiedenen Kulturbedingungen" wird vom Umweltbundesamt gefördert und von Universität Karlsruhe, Zoologisches Institut durchgeführt. Objective: The project aims: - to identify levels of growth promoting/anabolic and growth-reducing/catabolic hormones in fish subjected to different culture conditions (nutrition, salinity); - to develop recommendations for practical fish culture how to stimulate growth processes and how to minimize growth reducing processes by adequate feeding and culture conditions. As experimental species, Dicentrarchus labrax, Sparus auratus and Scophthalmus maximus have been selected. General Information: Four experimental approaches will be in the centre of the project: The ontogenetic pattern and the role of hormones during the development of larval Scophthalmus maximus and evaluation of rearing conditions in respect to hormonal actions. Influences of salinity and temperature, endocrine and metabolic changes of Sparus aurata and Dicentrarchus labrax kept under different external salinity and temperature. Influence of nutrition and diurnal feeding regimes on endocrine and metabolic profiles of Dicentrarchus labrax and/or Sparus aurata. Zootechnical studies for practical fish culture. The following parameters will be considered in the experiments planned: Growth parameters: growth rate, condition index; food ingestion, feed conversion; protein efficiency ratio. Physiological parameters: - General: lipid content, liver somatic index, muscle-somatic index - Liver: lipid, glycogen, protein, ash and water content, enzyme activities - Muscles: same metabolites as in the liver, lipid content, glycogen content - Serum: electrolyte and osmotic concentration, metabolite concentration (glucose, fatty acids, amino acids, total lipids). Hormone activity: - Serum titres: cortisol, T4/T3, insulin, glucagons. Histological, electron microscopical, immunohistochemical inspections: interrenal gland, endocrine pancreas, liver. Achievements: Studies with larval turbots, Scophtalmus maximus evaluated the functional status of organ systems involved in processing exogenous food with respect to survival and growth of early life stages. Intestine, exocrine pancreas and liver are differentiated at hatching or at the onset of exogenous feeding. Enzymes like aminopeptidase are found at the microvillus border. In contrast, evidence that differentiation is finished during metamorphosis is demonstrated for stomach, gills and glucolytic activity of muscles. The status of the thyroid hormone system was measured. The content of thyroxine (T4), triiodothyronine (T3) and the activity of monodeiodinase (MDI) were determined. From hatching until day 50 after hatching about 10 pg/mg body weight of T3 and high activity of MDI were found in the microsomal fraction of the liver. The influence of salinity and temperature on morphological and physiological changes in Dicentrarchus labrax (D) and Sparus auratus (S) were monitored. Differences in the growth rate for D are found when kept in 1.2 per cent salinity instead of 3.5 per cent at 18 C...
Types:
SupportProgram
Origin: /Bund/UBA/UFORDAT
Tags: Hirsch ? Goldbrasse ? Karlsruhe ? Fischart ? Glukose ? Plattfisch ? Populationsdynamik ? Aminosäure ? Fettsäure ? Larve ? Meeresfisch ? Ingestion ? Asche ? Elektrolyt ? Fischbestand ? Lipid ? Mikrosom ? Morphologie ? Osmose ? Physiologie ? Pflanzensamen ? Temperaturverteilung ? Zoologie ? Elektronenmikroskopie ? Immunoassay ? Ökologische Bestandsaufnahme ? Aufbereitungstechnik ? Enzym ? Fischzucht ? Stoffwechselprodukt ? Versuchstier ? Futtermittel ? Habitat ? Metamorphose ? Salzgehalt ? Niere ? Ontogenese ? Hormon ? Leber ? Protein ? Studie ? Magen-Darm-Trakt ? Tierernährung ? Wassergehalt ? Wirkungsanalyse ? Drüse ? Nährstoffkreislauf ? Endokrin aktive Substanz ? Lebensmittel ? Organ ? Züchtung ? Fischerei ? Ernährung ? Kenngröße ? Enzymaktivität ? Handlungsorientierung ? Bauchspeicheldrüse ? Histologie ? Konzentrationsmessung ? Muskel ? Untersuchungsprogramm ? Wachstum [biologisch] ? resources of the sea ?
Region: Baden-Württemberg
Bounding box: 9° .. 9° x 48.5° .. 48.5°
License: cc-by-nc-nd/4.0
Language: Deutsch
Time ranges: 1991-03-01 - 1994-03-01
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