**Acknowledgements**

Thanks to Research and Development Direction from Austral University of Chile, by support to Laboratory of Cryobiology and Spermatic Function Analysis. Special thanks to all profes‐ sional and technical personnel of the Center of Artificial Insemination, that from the 1960s set up and development the bovine semen cryopreservation in Chile and whose seminal doses stored for long term has made this study possible.
