Sökning: "Salmonid fish"

Visar resultat 21 - 25 av 36 avhandlingar innehållade orden Salmonid fish.

  1. 21. Lake bathymetry as driver of salmonid population size structure and biomass

    Författare :Sven Norman; Pär Byström; Karin A. Nilsson; Jan Karlsson; Per-Arne Amundsen; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Lake bathymetry; habitat-specific resource production; ontogenetic niche shifts; size structure; Arctic char; brown trout; populationsbiologi; Population Biology; Limnology; limnologi; zooekologi; Animal Ecology;

    Sammanfattning : Most fish species undergo ontogenetic niche shifts from feeding on pelagic zooplankton, to larger benthic invertebrates and in some cases also to fish. These ontogenetic niche shifts have strong impact on the interactions within and between species, with effects on individual growth, population abundance and food web dynamics. LÄS MER

  3. 22. NMR metabolomics and lipid analyses in salmonid tissue : response to alternative feeds

    Författare :Liane Wagner; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES;

    Sammanfattning : Salmonids are fatty fish and contain high amounts of omega-3 polyunsaturated fatty acids, beneficial in human nutrition. However, the aquaculture industry has expanded greatly in recent decades, increasing demand for fishmeal (FM) and fish oil (FO) for fish feed, while the supply of fish raw materials has remained static or declined. LÄS MER

  4. 23. The estrogen receptor in fish and effects of synthetic estrogens in the environment - Ecological and evolutionary perspectives and societal awareness

    Författare :Lina Nikoleris; Biodiversitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; the estrogen receptor; salmon evolution and ecology; contraceptives; information gaps; synthetic hormones; EE2; Atlantic salmon Salmo salar ; brown trout Salmo trutta ; roach Rutilus rutilus ;

    Sammanfattning : Synthetic hormones are a group of pharmaceuticals used for various human and animal treatments. However, consumption and disposal of these substances have also given rise to negative effects and environmental problems for organisms in the wild which is why these substances have been classified as estrogenic endocrine-disrupting chemicals (EDCs). LÄS MER

  5. 24. Parasite host interaction between the freshwater pearl mussel (Margaritifera margaritifera) and brown trout (Salmo trutta) – the impact from glochidia larvae on the host

    Författare :Niklas Wengström; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Parasites can modulate the physiology and behavior of the hosts to enhance their chances to complete their life cycle. The numerous freshwater bivalves of the order Unionoida all have a parasitic larval stage, also known as glochidia, parasitizing fish hosts. LÄS MER

  7. 25. Conservation of landlocked Atlantic salmon in a regulated river : Behaviour of migratory spawners and juveniles

    Författare :Anna Hagelin; Eva Bergman; Fleming Ian; Karlstads universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Atlantic salmon; conservation; migration; spawning; hydropower; competition; juveniles; brown trout; hatchery reared; fallback; delay; Biology; Biologi;

    Sammanfattning : Hydropower dams represent one of the major threats to river ecosystems today. The dams block migratory routes in many rivers, which is problematic for migratory fish species. Trap-and-transport may be an alternative to fish passage solutions, as a strategy to compensate for lost river connectivity. LÄS MER