Cryopreservation and transport of mouse spermatozoa at -79 degrees C.
In the present study, 2 experiments were carried out. In experiment 1, mouse spermatozoa were frozen and stored in an ultra-low temperature freezer maintained at -79 degrees C, from 1 week to 8 months. In vitro fertilization rates of the frozen-thawed sperm after 1 week and 4 months of storage were high at 71 and 71%, respectively. These values did not differ significantly from the value (73%) of the control stored at -196 degrees C. In contrast, the 8-month storage rate was significantly lower at 51%. In experiment 2, frozen spermatozoa were transported in a Styrofoam box packed in dry ice from Hokkaido to Tokyo. In vitro fertilization rate of frozen-thawed sperm after transport at -79 degrees C was high at 88%, which was not significantly different from that (84%) of the transported control at -190 degrees C. After transferring two-cell embryos derived from frozen spermatozoa to recipients, 37-62% of the embryos developed into offspring in both experiments. These results indicate that mouse spermatozoa can survive cryopreservation in an ultra-low temperature freezer (-79 degrees C) for up to 4 months and transport at -79 degrees C.
Okamoto
M
M
Animal Breeding and Reproductive Biotechnology Laboratory, National Institute of Radiological Sciences, Anagawa 4-9-1, Inage-ku, Chiba-shi 263-8555, Japan.
Nakagata
N
N
Toyoda
Y
Y
D000818:Animals; D002470:Cell Survival; D015925:Cryopreservation; D005307:Fertilization in Vitro; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D013048:Specimen Handling / Q000379:methods*; D013081:Sperm Motility; D013094:Spermatozoa / Q000502:physiology*; D013997:Time Factors