Sökning: "egg production"

Visar resultat 11 - 15 av 60 avhandlingar innehållade orden egg production.

  1. 11. MODEL STUDIES OF FISH EGG AND LARVAL TRANSPORT IN THE KATTEGAT AND THE NORTH ATLANTIC

    Författare :Selma Pacariz; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Oceanography; Fisheries;

    Sammanfattning : For the early life stages of fish, the dispersal and retention are important factors regarding present and future survivorship, growth and reproduction. The main objective of this thesis is to analyse fish egg and larval transport in two different marine systems, the Kattegat and the North Atlantic. LÄS MER

  3. 12. The ecology of the plankton fauna in the Gulf of Bothnia

    Författare :Olof Sandström; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Zooplankton; ecology; the Baltic; selective predation production biology; patchiness;

    Sammanfattning : The geographical distribution of the Gulf of Bothnia zooplankton species is presented together with observations of abundancies and vertical distributions. The historical development of this plankton community in the last 70 years is discussed.Spring and summer development of the plankton fauna was studiedin the Bothnian Bay. LÄS MER

  4. 13. Modeling Atlantic salmon (Salmo salar) and brown trout (Salmo trutta) responses to river habitat alteration

    Författare :Kristine Lund Bjørnås; John Piccolo; Olle Calles; Steven F. Railsback; Leif Asbjørn Vøllestad; Karlstads universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Ecohydraulics; Restoration; Natural resource management; Biology; Biologi;

    Sammanfattning : Half the world’s river volume is affected by flow alterations and/or fragmentation, a figure that is likely to increase with the current global surge in hydropower development. At the same time, freshwater biodiversity is in rapid decline. LÄS MER

  5. 14. Teleost reproduction: Aspects of Arctic char (Salvelinus alpinus) oocyte growth and maturation

    Författare :Håkan Berg; Per-Erik Olsson; Birgitta Norberg; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Zoophysiology; Salmonid; oocyte growth; vitellogenin; vitelline envelope protein; stress; cortisol; oocyte maturation; membrane receptor; Zoofysiologi; Animal physiology; Zoofysiologi; Zoophysiology; zoofysiologi;

    Sammanfattning : In all vertebrate species, reproduction is a hormonally controlled process, important for growth and maturation of gonads and germ cells. Production of functional germ cells is of outmost importance to secure the survival of a species. Fish comprises 50% of the known vertebrates and are found in aquatic habitats all over the world. LÄS MER

  7. 15. Reproductive performance of farmed Arctic charr

    Författare :Henrik Jeuthe; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES;

    Sammanfattning : The production of farmed Arctic charr (Salvelinus alpinus) has increased rapidly over the last decade, and the industry is predicted to continue to grow in the coming years. One major bottleneck for this future expansion concerns the supply of viable eggs and juveniles. LÄS MER