Effect of different concentrations of permeable and non–permeable cryoprotectants on the hatching rate of goldfish (Carassius auratus) embryos

ObjectiveTo assess the toxicity of various cryoprotective agents(CPAs) to goldfish embryos.MethodsHeart–beat embryos were immersed in: five permeable CPAs, dimethyl sulfoxide (DMSO), methanol (MeOH), 1,2– propylene glycol (PG), glycerol (Gly), ethylene glycol (EG), and two non–permeable CPAs: polyvinylpyrrolidone (PVP) and sucrose in concentrations of 5%, 10%, 15% or 20% for 5, 15, or 30 min. The viability of the embryos after the treatments was estimated from hatching rates.ResultsThe results showed that the toxicity to goldfish embryos of the five permeable CPAs were in the following sequence: PG < DMSO < MeOH < EG ∼ Gly (greater symbols mean P < 0.05, and approximate symbols mean P > 0.05). In this experiment none of the concentrations tested for sucrose reduced the hatching rate, but embryos exposed to PVP did not tolerate concentration 20%, at 30 min exposure.ConclusionThese finding will be advantageous for designing optimized Cryo–media for cryopreservation of goldfish embryos