Characterization of oocyte development in hatchery-reared burbot

• Published in: North American Journal of Aquaculture
• Main Authors: Foltz, JR, Jensen, NR, Polinski, MP, Ireland, SC, Cain, KD
• Format: Article in Journal/Newspaper
• Language: English
• Published: Amer Fisheries Soc 2012
• Subjects: Agricultural and Veterinary Sciences; Fisheries Sciences; Aquaculture; Burbot; Lota lota; lota
• Online Access: https://doi.org/10.1080/15222055.2012.676001; http://ecite.utas.edu.au/82867

Burbot Lota lota are an emerging aquaculture species. To aid inpredicting the natural and hormonal-manipulated timing of ovulationand for ensuring maximum viability of eggs at spawning,this study describes oocyte maturation of hatchery-reared burbotfrom vitellogenesis through ovulation. At a temperature of 4C,visual polarization of the oil globule occurred 713 d preovulation.The lack of uniformity in individual oocyte development was observedand persisted until approximately 2 d before ovulation, atwhich point complete polarizationwas observed in all oocytes and acondensed blastomere was observed along the inner chorion. Thesepreliminary observations imply that implantation of gonatotropinreleasinghormone (GnRH) decreased the final maturation stageof oocyte development by 24 d and may aid in initiating the maturationprocess, the induction of which appeared to be a thresholdfor either a females progression to ovulation or nonovulation andatresia. Although additional investigation may be needed to fullymaximize egg fertilization success and optimize timing related tointensive spawning practices, this study lays a foundation for further investigations and provides a reference for assessing oocytedevelopment and predicting ovulation for this species.