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Untersuchung zur in vivo-Wirkung von Zearalenon auf funktionelle Parameter ovarieller, Eileiter- und endometrialer Zellen beim Schwein

Mykotoxine sind Metaboliten des Sekundärstoffwechsels mikroskopisch kleiner Pilze, vor allem der Gattung Aspergillus, Penicillium und Fusarium. In bestimmten Konzentrationen wirken sie toxisch für Mensch, Tier und Pflanze. Die als Feldpilze bekannten Fusarien bilden Mykotoxine (Trichothezen und Zearalenon) zum Teil schon während der Wachstums- und Reifungsphase des heimischen Futtergetreides und beim Mais. Trichothezen (Deoxynivalenol, DNO) übt eine zytotoxische Wirkung aus, indem es die Protein- und DNA-Synthese hemmt. Aufgrund seiner hohen Zytotxizität greift die Substanz an verschiedenen Systemen des Körpers ein, so dass infolge einer Abwehrschwäche Fruchtbarkeitsstörungen (Unfruchtbarkeit, Umrauschen), Aborte, Totgeburten und mimifizierte Früchtte sowie Uterusatrophie bei Sauen insbesondere bei Jungsauen aufgetreten sind. Im Gegensatz dazu sind die Zearalenone nicht toxisch. Ihre Aktivität im Tier besteht in einer östrogenen Wirkung, die zu Veränderungen an den Fortpflanzungsorganen und zu Fruchtbarkeitsstörungen beim Schwein führen. Ein Einfluss von Mykotoxin auf die Fruchtbarkeit wurde bisher weitgehend nach Fütterung von mykotoxin-haltigen Futtermitteln beobachtet. Grundlagenerkenntnisse über direkte negative Einflüsse von Mykotoxinen auf die Fruchtbarkeit können mit Hilfe von Untersuchungen mittels In-vitro-Kultivierung von Eizellen und Embryonen, ovariellen und uterinen Zellen gewonnen werden. Die physiologische Aktivität der genannten Zelltypen des weiblichen Reproduktionstraktes kann über funktionelle Tests gemessen werden, die ihrerseits darüber Auskunft geben, in welchem Maße die Leistungen dieser Zellen bzw. Embryonen störanfällig gegenüber Zearalenon und Trichothezen sind.

Reproductive parameters and oocyte fatty acid compositions in European sprat Sprattus sprattus sampled in the Baltic Sea

Fecundity of marine fish species is highly variable, but trade-offs between fecundity and egg quality have rarely been observed at the individual level. We investigated spatial differences in reproductive investment of individual European sprat Sprattus sprattus (Linnaeus 1758) females by determining batch fecundity, condition indices (somatic condition index and gonadosomatic index) as well as oocyte dry weight, protein content, lipid content, spawning batch energy content, and fatty acid composition. Sampling was conducted in five different spawning areas within the Baltic Sea between March and May 2012. Sampling was conducted in the Baltic Sea during three cruises of the German RV “Alkor” in March (https://www2.bsh.de/aktdat/dod/fahrtergebnis/2012/20120331.htm), April (http://dx.doi.org/10.3289/CR_AL390), and May (http://dx.doi.org/10.3289/CR_AL392) 2012. Five different areas were sampled: KB, AB, Bornholm Basin (BB), Gdansk Deep (GD), and Gotland Basin (GB). Fish were caught with a pelagic trawl. Trawling time was in general 30 minutes per haul. The total lengths (TL, ±0.1 cm) of at least 200 sprat per haul were measured for length frequency analysis. Only female sprat with ovaries containing fully hydrated oocytes were sampled, running ripe females were rejected to avoid possible loss of oocytes, as this would lead to an underestimation of batch fecundity. Sprat were sampled immediately after the haul was on deck and stored on crushed ice. The sampled fish were weighed (wet mass WM, ±0.1 g) and measured (TL, ±0.1 cm), and their ovaries were dissected carefully. Oocytes were extracted from a single ovary lobe, rinsed with deionized water, and counted under a stereo microscope (Leica MZ 8). A counted number of oocytes (around 50 oocytes per fish) were transferred to pre-weighed tin-caps (8 x 8 x 15 mm). These samples were used to determine the oocyte dry weight, lipid content, and fatty acid composition. In addition, a counted number of oocytes (around 10 oocytes per fish) were sampled in Eppendorf caps for determination of protein content. Oocyte samples were stored at -80 °C for subsequent fatty acid and protein analysis in the laboratory. Finally, both ovary lobes were stored in 4% buffered formaldehyde solution for further fecundity analysis. Ovary free body mass (OFBM, ±0.1 g) of sampled frozen fish and fixed ovary mass (OM, ±0.1 g) were measured (Sartorius, 0.01 g) in the laboratory on land, to avoid imprecise measurements due to the ship's motion at sea. Absolute batch fecundity (ABF) was determined gravimetrically using the hydrated oocyte method suggested by Hunter et al. (1985) for indeterminate batch spawners. For ascertainment of the relative batch fecundity per unit body weight (RBF), ABF was divided by OFBM. Further, a condition index (CI) was determined: CI = (OFBM/〖TL〗^3 )× 100. A gonadosomatic index (GSI) was calculated with the following formula: GSI = (OM/OFBM)× 100. Oocyte dry weight was determined to the nearest 0.1 µg (Sartorius SC 2 micro-scale), using the samples stored in pre-weighed tin caps, after freeze-drying (Christ Alpha 1-4) for at least 24 hours. After subtracting the weight of the empty tin cap, the average oocyte dry mass (ODM) was then calculated by dividing the total weight by the number of oocytes contained in the tin cap. The fatty acid signature of oocytes was determined by gas chromatography (GC). Lipid extraction of the dried oocytes was performed using a 1:1:1 solvent mix of dichloromethane:methanol:chloroform. A five component fatty acid methyl ester Mix (13:0 - 21:0, Restek, Bad Homburg, Germany; c = 8.5 ng component µl-1) was added as an internal standard and a 23:0 fatty acid standard (Restek, Bad Homburg, Germany, c = 25.1 ng µl-1) was added as an esterification efficiency control. Esterification was performed over night at 50 °C in 200 µl 1% H2SO4 and 100 µl toluene. The solvent phase was transferred to 100 µl n-hexane and a 1 µl aliquot measured in a Thermo Fisher Trace GC Ultra with a Thermo Fisher TRACETM TR-FAME column (10 m*0.1 mm*0.2 µm). For more details on sample preparation and GC settings, see Hauss et al. (2012). The total lipid content per oocyte was determined by adding up the weights of all detected fatty acids. To ensure comparability with past studies, results for FA are given as a percentage of the combined weights of all detected FA. An average of 10 oocytes were transferred to 5*9 mm tin cups (Hekatech) and dried at 50 °C for >24 h. Total organic carbon (C) and nitrogen (N) content was measured using a Thermo Fisher Scientific Elemental Analyzer Flash 2000. From the total amount of N in the sample, the oocyte protein content was calculated according to Kjeldahl (Bradstreet, 1954), using a factor of 6.25. The oocyte gross energy content was calculated on the basis of measured protein and lipid content, which were multiplied with corresponding energy values from literature. The measured amount of proteins per given oocyte (P, mg) was multiplied by a factor of 23.66 J mg-1 and was added to the total amount of lipids per oocyte (L, mg) multiplied by 39.57 J mg-1 (Henken et al. 1986). Consequently, the oocyte energy content of each individual female sprat was multiplied by its relative batch fecundity in order to obtain a standardized estimate of the total amount of energy invested into a single spawning batch (SBEC, J g-1 OFBM): SBEC = [(P × 23.66 (J )/mg)+(L × 39.57 (J )/mg)]× RBF

Seawater carbonate chemistry and seasonal variations of Fucus vesiculosus fertility in the western Baltic Sea

Ocean warming and acidification may substantially affect the reproduction of keystone species such as Fucus vesiculosus (Phaeophyceae). In four consecutive benthic mesocosm experiments, we compared the reproductive biology and quantified the temporal development of Baltic Sea Fucus fertility under the single and combined impact of elevated seawater temperature and pCO2 (1100 ppm). In an additional experiment, we investigated the impact of temperature (0–25°C) on the maturation of North Sea F. vesiculosus receptacles. A marked seasonal reproductive cycle of F. vesiculosus became apparent in the course of 1 year. The first appearance of receptacles on vegetative apices and the further development of immature receptacles of F. vesiculosus in autumn were unaffected by warming or elevated pCO2. During winter, elevated pCO2 in both ambient and warmed temperatures increased the proportion of mature receptacles significantly. In spring, warming and, to a lesser extent, elevated pCO2 accelerated the maturation of receptacles and advanced the release of gametes by up to 2 weeks. Likewise, in the laboratory, maturation and gamete release were accelerated at 15–25°C relative to colder temperatures. In summary, elevated pCO2 and/or warming do not influence receptacle appearance in autumn, but do accelerate the maturation process during spring, resulting in earlier gamete release. Temperature and, to a much lesser extent, pCO2 affect the temporal development of Fucus fertility. Thus, rising temperatures will mainly shift or disturb the phenology of F. vesiculosus in spring and summer, which may alter and/or hamper its ecological functions in shallow coastal ecosystems of the Baltic Sea.

Seawater carbonate chemistry and gastric pH homeostasis and larval recruitment in the sea star Asterias rubens

Aim: Experimental simulation of near‐future ocean acidification (OA) has been demonstrated to affect growth and development of echinoderm larval stages through energy allocation towards ion and pH compensatory processes. To date, it remains largely unknown how major pH regulatory systems and their energetics are affected by trans‐generational exposure to near‐future acidification levels. Methods: Here, we used the common sea star Asterias rubens in a reciprocal transplant experiment comprising different combinations of OA scenarios, to study trans‐generational plasticity using morphological and physiological endpoints. Results: Acclimation of adults to pHT 7.2 (pCO2 3500 μatm) led to reductions in feeding rates, gonad weight and fecundity. No effects were evident at moderate acidification levels (pHT 7.4; pCO2 2000 μatm). Parental pre‐acclimation to pHT 7.2 for 85 days reduced developmental rates even when larvae were raised under moderate and high pH conditions, whereas pre‐acclimation to pHT 7.4 did not alter offspring performance. Microelectrode measurements and pharmacological inhibitor studies carried out on larval stages demonstrated that maintenance of alkaline gastric pH represents a substantial energy sink under acidified conditions that may contribute up to 30% to the total energy budget. Conclusion: Parental pre‐acclimation to acidification levels that are beyond the pH that is encountered by this population in its natural habitat (eg, pHT 7.2) negatively affected larval size and development, potentially through reduced energy transfer. Maintenance of alkaline gastric pH and reductions in maternal energy reserves probably constitute the main factors for a reduced juvenile recruitment of this marine keystone species under simulated OA.

LEP Umwelt 2004 Vorranggebiete für Landwirtschaft Saarland

Flächenhafte Darstellung der Vorranggebiete für Landwirtschaft im Rahmen des Landesentwicklungsplan Umwelt. In Vorranggebieten für Landwirtschaft (VL) geht die landwirtschaftliche Nutzung allen anderen Nutzungen vor. Die Inanspruchnahme landwirtschaftlicher Vorranggebiete für Zwecke der Siedlungstätigkeit (Wohnen, Industrie und Gewerbe, Dienstleistungen sowie Freizeitvorhaben) ist unzulässig. Grundlage sind Gebiete, die im Rahmen der Agrarstrukturellen Entwicklungsplanung erhoben wurden. Sie umfassen Flächen, die entweder aufgrund ihrer natürlichen Fruchtbarkeit von hervorragender Bedeutung für die Nahrungsmittelerzeugung sind oder die aufgrund ihrer Hof nahen Lage und Flächenstruktur für entwicklungsfähige, landwirtschaftliche Betrieb existenzbegründend sind.

Entwicklung und Validierung von in vitro Assays zur Untersuchung von Chemikalien auf die Schilddrüsenhormon-Homöostase, Massenspektrometrie

Entwicklung und Validierung von in vitro Assays zur Untersuchung von Chemikalien auf die Schilddrüsenhormon-Homöostase, Zelllinien & Assays

Modelluntersuchungen zur Steigerung der Fruchtbarkeit armer Savannenböden in Mosambik durch 'Biochar'-Applikation

Quantifizierung der Ertragswirksamkeit von Biokohlegaben ('Biochar') in Feldexperimenten ('Biochar'-Steigerungsversuche auf Kleinparzellen mit zwei unterschiedlichen Kulturen) in Mosambik auf Jatropha-Produktionsstandorten der Elaion AG.

Development of a modelling system for prediction and regulation of livestock waste pollution in the humid tropics

Introduction: In Malaysia, excessive nutrients from livestock waste management systems are currently released to the environment. Particularly, large amounts of manure from intensive pig production areas are being excreted daily and are not being fully utilised. Alternatively, the excess manure can be applied as an organic fertiliser source in neighbouring cropping systems on the small landholdings of the pig farms to improve soil fertility so that its nutrients will be available for crop uptake instead of being discharged into water streams. Thus, there is a need for better tools to analyse the present situation, to evaluate and monitor alternative livestock production systems and manure management scenarios, and to support farmers in the proper management of manure and fertiliser application. Such tools are essential to quantify, and assess nutrient fluxes, manure quality and content, manure storage and application rate to the land as well as its environmental effects. Several computer models of animal waste management systems to assist producers and authorities are now available. However, it is felt that more development is needed to adopt such models to the humid tropics and conditions of Malaysia and other developing countries in the region. Objectives: The aim is to develop a novel model to evaluate nutrient emission scenarios and the impact of livestock waste at the landscape or regional level in humid tropics. The study will link and improve existing models to evaluate emission of N to the atmosphere, and leaching of nutrients to groundwater and surface water. The simulation outputs of the models will be integrated with a GIS spatial analysis to model the distribution of nutrient emission, leaching and appropriate manure application on neighbouring crop lands and as an information and decision support tool for the relevant users.

Hypothermie als Anpassung zur Energieeinsparung in Zeiten der Unterernährung

In marinen Ökosystemen kann der Klimawandel zu einem geringeren Nahrungsangebot und einer Zunahme von Extremwettern führen. Tiere, die unter diesen Bedingungen leben, müssen die physiologischen Prozesse anpassen, die für das Wachstum, das Überleben und die Fortpflanzungsfähigkeit entscheidend sind. Ein grundlegender Prozess in der ökologischen Energetik ist die Thermoregulation, und Sturmvögel reagieren mit Hypothermie auf Mangelernährung. Ziel der geplanten Studie ist es, Anpassung von Seevögeln an vorhersehbare und unvorhersehbare Schwankungen in der Versorgung besser zu verstehen. Dafür werden wir Thermoregulationsmuster untersuchen, einerseits von brütenden (fastenden) Altvögeln in Reaktion auf die vorhersehbare Abnahme der Körperreserven und andererseits von Nestlingen, die von der elterlichen Versorgung abhängig sind, und damit unvorhersehbare Schwankungen in der Versorgung erfahren. Wir werden die thermoregulatorischen Anpassungen identifizieren, die Nestlingen helfen, eine positive Energiebilanz zu erreichen, wenn sie unregelmäßigen Fütterungen erfahren. Bei Altvögeln untersuchen wir Schlüsselereignisse im Jahreszyklus, nämlich das Fasten während der Brutzeit und die Schlupfzeit der Küken. Mithilfe von RFID-Temperaturaufzeichnungen und CaloBox-Stoffwechselmessungen werden wir ermitteln, wie viel Energie durch eine Absenkung der Körpertemperatur eingespart werden kann. Wir werden auch feststellen, welche Folgen dies für die Entwicklung des Nestlings hat. Als Modellart für die Untersuchung von Hypothermie werden wir Dünnschnabel-Walvögel untersuchen, eine kleine Seevogelart, die in kalten Wetterbedingungen brütet und in der subantarktischen Meeresumwelt einem schwankenden Nahrungsangebot ausgesetzt ist.

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