On the subzero temperature preservation of fertilized eggs of rainbow trout

A possibility of preservation of fertilized eggs of rainbow trout Salmo gairdneri was examined at-7°C-20°C for 3 hours. The results obtained are summarized as follows; 1. Eggs after eyed stage had higher tolerance for subzero temperature expisure than those of before eyed stage. 2. Suitable concentration of dimethyl sulfoxide (DMSO) as organic cryoprotectant was 1.4-2.1M. 3. In-7°C exposure, about95%of hatching rate was obtained by using10%calf serum and mineral saltion besides DMSO as cryoprotectants, while14%of hatching rate was obtained in -12°C exposure.