• myGriffith
    • Staff portal
    • Contact Us⌄
      • Future student enquiries 1800 677 728
      • Current student enquiries 1800 154 055
      • International enquiries +61 7 3735 6425
      • General enquiries 07 3735 7111
      • Online enquiries
      • Staff phonebook
    View Item 
    •   Home
    • Griffith Research Online
    • Journal articles
    • View Item
    • Home
    • Griffith Research Online
    • Journal articles
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Browse

  • All of Griffith Research Online
    • Communities & Collections
    • Authors
    • By Issue Date
    • Titles
  • This Collection
    • Authors
    • By Issue Date
    • Titles
  • Statistics

  • Most Popular Items
  • Statistics by Country
  • Most Popular Authors
  • Support

  • Contact us
  • FAQs
  • Admin login

  • Login
  • Additive effects of advanced temperature and photoperiod regimes and LHRHa injection on ovulation in Atlantic salmon (Salmo salar)

    Author(s)
    King, HR
    Pankhurst, NW
    Griffith University Author(s)
    Pankhurst, Ned W.
    Year published
    2007
    Metadata
    Show full item record
    Abstract
    In order to evaluatemanipulation of spawning time as a potentialmeans to extend 0+ Atlantic salmon (Salmo salar) smolt production in Tasmania, Australia, female salmon were exposed to a natural/simulated natural (42ө photoperiod or an advanced (L:D 9:15) photoperiod from the austral summer solstice (20 December) under natural or advanced (~6 àbelow natural temperature) temperature conditions. In late summer (26 February) injections of a commercial LHRHa preparation or vehicle (propylene glycol) commenced. Regular ovulation checks were conducted and ova were fertilised using milt from LHRHa-injected males held under matching ...
    View more >
    In order to evaluatemanipulation of spawning time as a potentialmeans to extend 0+ Atlantic salmon (Salmo salar) smolt production in Tasmania, Australia, female salmon were exposed to a natural/simulated natural (42ө photoperiod or an advanced (L:D 9:15) photoperiod from the austral summer solstice (20 December) under natural or advanced (~6 àbelow natural temperature) temperature conditions. In late summer (26 February) injections of a commercial LHRHa preparation or vehicle (propylene glycol) commenced. Regular ovulation checks were conducted and ova were fertilised using milt from LHRHa-injected males held under matching photothermal conditions. Plasma levels of 17߭estradiol (E2) and testosterone (T) were monitored and reproductive success (cumulative % ovulation,%fertilisation and%survival to the eyed-egg stage)was recorded.Ovulations commenced first (09 March) inLHRHa-treated fish that experienced advanced photoperiod and thermal regimes whereas sham-treated fish exposed to natural photoperiod and temperature conditions where the last to ovulate (22 May-08 June). Treatment-related sequential changes in the timing of ovulations were reflected by sequential advances in the timing of peaks in plasma levels of E2 and T. The fertilisation of ova from LHRHa-treated fish that experienced advanced photoperiod and thermal regimes was significantly reduced (~52%) relative to all other treatments (N80%) but there were no significant treatment-related differences in the survivals of eggs to the eyed stage (~50-90%). Consequently, a maximum advance in the timing of median ovulation of 71 days and commercially acceptable eyed-egg yields were generated, demonstrating that combinations of photoperiod, thermal and hormone treatments may be employed to significantly extend spawning and thereafter increase the availability of 0+ smolts for grow-out.
    View less >
    Journal Title
    Aquaculture
    Volume
    273
    Issue
    4
    DOI
    https://doi.org/10.1016/j.aquaculture.2007.07.008
    Subject
    Zoology
    Fisheries sciences
    Publication URI
    http://hdl.handle.net/10072/17971
    Collection
    • Journal articles

    Footer

    Disclaimer

    • Privacy policy
    • Copyright matters
    • CRICOS Provider - 00233E

    Tagline

    • Gold Coast
    • Logan
    • Brisbane - Queensland, Australia
    First Peoples of Australia
    • Aboriginal
    • Torres Strait Islander