Cryopreservation of Limnoperna fortunei (golden mussel) sperm with polyethylene glycol

Background. Insufficient quantities of freshly harvested Limnoperna fortunei gametes and embryos constrain reproduction research in the laboratory. Cryopreservation would allow the accumulation and storage of gametes when they are available. The lack of available cryopreservation protocol for Limnoperna fortunei in the literature led our research group to undertake a study to establish which cryoprotective agents can be might be most useful for cryopreservation of this species’ sperm. Methods. 2%, 5%, and 10% concentration of ethylene glycol, dimethyl sulfoxide, glycerol, and polyethylene glycol 4000 as well as 0.2 M glucose, sucrose, and trehalose (mixed into the 10% concentration of the aforementioned agents) were tested in a 1:1 ratio with sperm, in 0.25 ml straws, frozen in liquid nitrogen. Results. After 48 hours the best survival rate was in the samples with 10% polyethylene glycol 4000, 36.1%, which also resulted in viable sperm after 7 and 15 days.