Is the conservation of goat semen at -150°C a viable alternative?

A series of experiments was carried out to validate a -150 °C ultra-low temperature freezer for its possible use to properly freeze and store semen. In the first part, rude sample handling was simulated to see whether temperature of stored samples was maintained within a safe range; also, the freezing point and latent heat of fusion plateau of a semen extender were monitored. In the second part, buck semen was (1) frozen in liquid nitrogen and stored in the ultra-low freezer, (2) frozen and stored in the ultra-low freezer, and (3) frozen and stored in liquid nitrogen, to compare sperm cryosurvival between freezing methods. Both, frequent removal of samples and long opening of the freezer door did not negatively affect stored samples’ temperature; latent heat of fusion plateau was five minutes long. Semen stored either at- 150 or at-196 °C. cryosurvived similarly after two days and two months of cryopreservation.