FR 11. Evaluation of bovine semen frozen in french straws after 10 expositions to environment

This study was developed to evaluate the cumulative effects and possible injuries that could happen when the straws of 0.5 mL, are exposed to environmental temperature for ten seconds up to ten times. Ejaculates of five bulls were used for freezing. The sperm motility and vigour were analysed after thawing and after thermoresistance test (30 minutes at 46 °C). The acrosomal integrity was evaluated under fase contrast microscopy imediate after thawing. The results indicate that sperm motility and vigor post thawing was significantly affected after five expositions, but the acrosome was affected after the third exposition, and the injuries were more clearly observable after the thermal resistence test