Bibliothek

feed icon rss

Ihre E-Mail wurde erfolgreich gesendet. Bitte prüfen Sie Ihren Maileingang.

Leider ist ein Fehler beim E-Mail-Versand aufgetreten. Bitte versuchen Sie es erneut.

Vorgang fortführen?

Exportieren
Filter
Materialart
Erscheinungszeitraum
  • 1
    Digitale Medien
    Digitale Medien
    Oxford, UK : Munksgaard International Publishers
    Ecology of freshwater fish 14 (2005), S. 0 
    ISSN: 1600-0633
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie , Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract –  Genetic data on archaeological specimens provide complementary information for addressing questions on distribution and migration of fishes over long time scales. In this study DNA was extracted from common bream bones (N = 4), dated c. 6000–1000 bp, and a 172 bp fragment of mitochondrial cytochrome b gene has been sequenced. The obtained sequences differed from homologous sequences of breams living contemporarily (N = 4), inhabiting the same geographical areas as ‘ancient’ fish. None of ancient mitochondrial haplotype was found in fish living at present. Our results suggest that fish vicariance could be affected also by other than glacial retreat historical events, and the mechanisms that influenced present distribution of freshwater fishes are still unclear.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 2
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Journal of fish biology 61 (2002), S. 0 
    ISSN: 1095-8649
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: Androgenetic development of salmonid embryos was induced in recipient oocytes from the same or other species (intra- or interspecies androgenesis). Parameters for induced androgenesis were investigated in brown trout Salmo trutta and brook trout Salvelinus fontinalis. Reciprocal androgenetic and control crosses were conducted among fishes from three genera: Oncorhynchus (rainbow trout, O. mykiss), Salmo (brown trout) and Salvelinus (brook trout), and within two genera: Salmo (brown trout and Atlantic salmon, S. salar) and Salvelinus (brook trout and Arctic charr, S. alpinus). Live hatched androgenetic progenies were obtained in all intraspecies variants, where oocytes and sperm originated from the same species. Interspecies androgenesis resulted in no viable larvae, despite the fact that most hybrid controls and intraspecies androgenetic individuals were viable. When recipient oocytes originated from other genera (interspecific intergeneric androgenesis), embryonic development ceased in early developmental stages, except for haploid controls of brook trout produced in eggs of brown trout. Survival of embryos to the eyed-egg stage was relatively high in the intrageneric androgenesis experiment. Nevertheless, none of these embryos survived to hatching. Some of the presumed Atlantic salmon individuals developing in brown trout eggs contained maternal DNA, questioning the accuracy of enucleation using irradiation. The inability to induce interspecific androgenesis among the examined salmonid species may have been the result of substantial kariotypical and developmental differences between spermatozoal donors and oocyte recipients, causing an incompatibility between maternal cytoplasmic regulatory factors and the paternal nuclear genome.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
Schließen ⊗
Diese Webseite nutzt Cookies und das Analyse-Tool Matomo. Weitere Informationen finden Sie hier...