Immediately after the collection, the semen is evaluated, and if the quality is good, it is mixed with substances to dilute and cryoprotect for its latter freezing at -196 ºC in liquid nitrogen.The packaging is done in 0,5cc straws with a concentration of 50-100 million living sperm.
Once frozen, one straw is then defrozen to evaluate the quality of the semen. Not every dog has the same semen quality after defreezing. The results vary from 50 to 70% of living sperm. A mortality up to 30% is within normal range.