CRYOPRESERVATION OF SPERM FROM ASP ASPIUS-ASPIUS

This is the first report on sperm cryopreservation for the cyprinid sp ecies asp Aspius aspius. Fish were captured from wild stock and kept u nder controlled conditions. Ovulation and spermiation were induced wit h hormonal treatment. Six simple carbohydrate-based extenders suppleme nted with 10% DMSO were tested for sperm cryopreservation. The most ef ficient extenders were 0.3 M sucrose, 0.6 M sucrose, and 0.3 M glucose . They resulted in survival to the eyed stage of 62 +/- 4%, 59 +/- 5%, and 49 +/- 4%. respectively, expressed as a percentage of control sur vival, which was 58 +/- 6%. The presence of chicken egg yolk in extend ers significantly decreased cryopreservation success.