Cryogenic Preservation of Atlantic Cod (<i>Gadus Morhua</i>) Sperm

Abstract

Cryogenic preservation of cod sperm, with retention of fertilizing capacity, was achieved. Sperm were deep frozen to −79 C or −196 C in the presence of protecting agents. Of the conditions tested, most satisfactory freezing was accomplished in a mixture containing 1 part semen and 3 parts of a medium that consisted of 40 parts 0.4 M NaCl − 0.1 M glycine: 8 parts of 1.3% sodium bicarbonate: 10 parts of glycerol. A freezing rate of 5 degrees C/min was more successful than one of 1 degree C/min.When frozen sperm were stored at −196 C for periods up to 60 days the average fertility was 36 ± 12% (seven samples) compared with 79 ± 6% (seven samples) for fresh sperm on the same batch of eggs. Successful storage of cod sperm at −79 C for a year was achieved.