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The problem of echo disruption has been frequently noted by authors who have studied parasites of harbor porpoise. Six harbor porpoises were examined macroscopically and microscopically for the occurrence of Stenums minor. The present investigation confirmed earlier observations that this nematode may probably cause auditory malfunction, as there were changes to the auditory nerves of the cochlea and middle ear in consequence of chronic or acute inflammation with parasitic infection in animals. Moreover, it can be stated that damage caused by S. minor produced severe stress and pain, which, very likely, affected the animal behavior.
Eleven parasite taxa were found infecting 68 Atlantic chub mackerel, Scomber colias Gmelin, 1789 from the Canary Islands, Central North Atlantic. The most abundant parasites were the gill monogenean Pseudokuhnia minor (P = 54.4%), larval anisakid nematodes (P = 11.8%) in the body cavity, a larval tetraphyllidean infecting bile ducts (P = 8.8%) and didymozoid digeneans infecting the gills (P = 7.4%). No correlation between fish length and abundance of infection with these parasites was found. Within the Atlantic, the comparison of present results with previous reports on the occurrence of parasites in this fish host, might suggest that there is more than one population unit of Atlantic chub mackerel in the Eastern Atlantic.
Przedstawiono skład i stężenia związków z grupy chlordanu w podskórnej tkance tłuszczowej morświnów złowionych jako przyłów w Zatoce Gdańskiej. Próbki ekstrahowano i oczyszczono metodą niedestrukcyjną z dializą przez membranę polietylenową. Wyciąg analizowano techniką kapilarnej chromatografii gazowej i niskorozdzielczej spektrometrii mas (HRGC/LRMS). Oznaczono stężenia heptachloru, U82, MC4, trans-chlordanu, MC5, cis- chlordanu, MC7, MC6, trans-nonachloru, cis-nonachloru, oksychlordanu i epoksydu heptachloru.
Over 700 specimens of Corynosoma strumosum (Rudolphi, 1802) Lühe, 1904 were collected from one young male Caspian seal, Pusa caspica (Gmelin) in the southern land-locked Caspian Sea in April, 2009. Collected worms showed consistent variations from those reported by other observers using light microscopy especially in proboscis hook and trunk spine patterns. SEM images revealed many features that have not been previously reported including the shape and distribution of trunk spines, dorsoventral differences in proboscis hooks and their organization, the baldness of anterior proboscis, the rough egg topography, epidermal micropores, and variations in the female gonopore. This isolated population of C. strumosum from the land-locked Caspian Sea is distinguished from others reported from open waters elsewhere by the distribution of trunk spines, consistently smaller size of trunk and testes, larger eggs, and fewer proboscis hooks. Histopathological sections reveal the invasive path of worms in host tissue with damage to intestinal villi and worm encapsulation. Information obtained from SEM studies and histopathological sections is reported for the first time.
This overview presents in detail the state of knowledge of the abilities of various components of the Baltic Sea environment to accumulate trace elements and radionuclides. Particular components of the Baltic ecosystem (abiotic and biotic) are considered as potential monitors of pollutants. The use of seaweeds, e.g. Fucus vesiculosus or Zostera marina is recommended, also molluscs, e.g. Mytilus edulis, for biomonitoring surveys of metal pollutants and radionuclides in the Baltic Sea. However, several requirements need to be met if results are to be reliable. Since metal levels and radionuclide activities in the growing tips of F. vesiculosus reflect exclusively the levels of their dissolved species in the ambient seawater, this alga is very useful for monitoring dissolved species of metal pollutants and radioisotopes in the Baltic ecosystem. In contrast, M. edulis, a filter feeder is an appropriate tool for monitoring trace elements occurring in both chemical forms, i.e. dissolved and suspended species. Therefore, full information on the bioavailability and toxicity of heavy metals (depending on their chemical speciation) as pollutants of the Baltic Sea can be obtained if at least two biomonitoring organisms are applied simultaneously, e.g. F. vesiculosus and M. edulis. Moreover, the data matrix can be interpreted more accurately if not only trace element but also macroelement concentrations (Ca, Mg, Na, K) in these two representatives of Baltic phytoand zoobenthos are taken into consideration; this point requires special attention. Two coastal species of fish, i.e. Zoarces viviparus and Perca fluviatilis, are good biomonitors of metallic contaminants, so their use as sentinels is recommended. The budgets of chemical elements and the ecological status of the Baltic Sea are presented. Several ‘blacksp ots’, e.g. large estuaries and seaport towns, heavily polluted by trace elements, are identified in the Baltic Sea and other enclosed seas such the Mediterranean and the BlackS eas. Of these seas, the Baltic is the most heavily loaded with trace elements and organic pollutants. The overview identifies gaps in our environmental knowledge of the Baltic Sea, and sets out possible priorities, key areas or strategies for future research.
Samples of stomach fundus and pylorus tissue collected from eight dogs experimentally infected with third-stage A. simplex В larvae were examined macro- and microscopically. The histopathological changes in these samples were analysed. Pathomorphological examination revealed that A. simplex В larvae actively penetrated the dog’s stomach wall within 2 days of infection. The presence of larvae in the mucous membrane was accompanied by tissue damage and cell infiltration predominantly by eosinophils.
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