Brood Stock Establishment through Hormonal Induction of Gamete Expression and Cryopreservation of Spermatozoa in Bloaters (Coregonus hoyi)

摘要

Animals raised in captivity typically exhibit reproductive dysfunction of varying degrees ranging from diminished to absent reproduction. This observation holds true for the bloater (Coregonus hoyi); a deepwater cisco extirpated from Lake Ontario. Efforts to rear bloaters in captivity have met with complications including the absence of egg expression in females and asynchronous gamete expression between sexes. As such, I examined whether the injection of an exogenous hormone (LHRHa) could induce gamete expression in both males and females. Also, I began the development of a sperm cryopreservation protocol for bloaters to overcome the observed asynchronous gamete expression. The exogenous hormone injections were effective at inducing the gamete expression of females, more so than males. Additionally, although the cryopreservation freezing rates examined were successful for closely-related species, they were not appropriate for bloater spermatozoa. However, all four extenders examined are suitable for bloater spermatozoa as none of them were biologically toxic.