Sökning: "egg production"

Visar resultat 26 - 30 av 60 avhandlingar innehållade orden egg production.

  1. 26. Transmission routes and vector potential of the poultry red mite Dermanyssus gallinae

    Författare :Sara Brännström; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES;

    Sammanfattning : The poultry red mite, Dermanyssus gallinae is a blood-feeding ectoparasite causing irritation, stress, and in severe infection, anemia and death of its avian host. This parasite not only causes welfare problems in poultry but also financial losses in egg production worldwide. The aims of this thesis were to elucidate the transmission routes of D. LÄS MER

  3. 27. Host plant choice, habitat selection, dispersal ability and population structure of a threatened butterfly, Lopinga achine

    Författare :Karl-Olof Bergman; Linköpings universitet; []
    Nyckelord :;

    Sammanfattning : Host plant choice, habitat selection and dispersal ability of the red-listed butterfly Lopinga achine were studied in partly open woodland in the province of Östergötland. Females preferred to oviposit near Carex montana, although they did not attach their eggs to any plant. LÄS MER

  4. 28. Anadromous Pike in the Baltic Sea

    Författare :Olof Engstedt; Per Larsson; Henrik Svedäng; Linnéuniversitetet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Marine ecology; Marin ekologi; Natural Science; Naturvetenskap;

    Sammanfattning : The pike (Esox lucius) is a major predator and top-down regulator in the Baltic Sea where it exists in two sympatric forms. One spawn in streams and rivers and the other one spawn in the sea. During the last decades, the habitats for both of these forms have developed in a negative way. LÄS MER

  5. 29. Microbes Associated with Hylobius abietis : A Chemical and Behavioral Study

    Författare :Muhammad Azeem; Anna Karin Borg-Karlson; Irena Valterová; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Hylobius; Ewingella; Penicillium; Heterobasidion; Bacteria; Fungi; Bark; Forest waste; Metabolites; Styrene; Methyl salicylate.;

    Sammanfattning : This thesis is based on three inter-related studies: the first part deals with the microbial consortium, the identification of microbes and their volatiles, the second part deals with the study of bio-chemical control methods of two conifer pests; the pine weevil Hylobius abietis (L.) and the root rot fungi Heterobasidion spp. LÄS MER

  7. 30. Reproductive physiology of the female three-spined stickleback, Gasterosteus aculeatus

    Författare :Chrysoula Roufidou; Bertil Borg; Geir Lasse Taranger; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; overripening of eggs; spawning cycle; brain-pituitary-gonad BPG axis; vitellogenin; ovarian fluid; sex steroids; reproduction; three-spined stickleback; Gasterosteus aculeatus; fish; funktionell zoomorfologi; Functional Zoomorphology;

    Sammanfattning : Reproduction in vertebrates, including fishes, is under control of the brain-pituitary-gonad (BPG) axis. The female three-spined stickleback, Gasterosteus aculeatus, produces egg clutches at intervals of a few days and spawns them in a nest built by male. LÄS MER