Cryopreservation of Sperm from AspAspius aspius

This is the first report on sperm cryopreservation for the cyprinid species asp Aspius aspius. Fish were captured from wild stock and kept under controlled conditions. Ovulation and spermiation were induced with hormonal treatment. Six simple carbohydrate-based extenders supplemented with 10% DMSO were tested for sperm cryopreservation. The most efficient 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 survival, which was 58 ± 6%. The presence of chicken egg yolk in extenders significantly decreased cryopreservation success.