Toxicity effect of cryoprotectant including: Glycerol, DMSO and Acetamide on Persian sturgeon (Acipenser persicus) embryos

Embryo cryopreservation means substantiation of the body water with a cryoprotectant. In this study, Persian sturgeon (Acipenser persicus) in two stages of embryonic development (24 and 48h post-fertilization) were exposed to various cryoprotectants including: glycerol, acetamide and dimethyl sulfoxid (DMSO) in concentration ranging from 1 to 6M for an equilibration period of 5 and 10 minutes. Embryos were then washed and incubated until hatched. Our results indicated that different concentrations of DMSO had less toxicity compared to glycerol and acetamide. Moreover, embryos could tolerate DMSO in high concentrations. Acetamid was found to be the most toxic as hatching rate decreased in high concentration of 3 and 4M in stages of embryonic developmental 24 and 48h post-fertilization, respectively. As concentrations were increased, hatching rate decreased (except DMSO in stage of 24h post-fertilization). Similarly, hatching rates of embryos were decreased as the exposure time increased (5 to 10 min). Twenty four hour embryos showed less sensitivity to DMSO and glycerol than to 48h embryos. With the increasing of the embryonic development sensitivity to acetamide were increased and hatching rates showed decreasing trend (hatching rate reached to 0% in concentrations above 3M).