Sperm Cryo-preservation

Sperm freezing is the fastest and most inexpensive method to cryo-preserve a genetically modified mouse line. However it does not ensure the conservation of homozygosity or recovery of an identical genetic background after thawing the sample and performing in vitro fertilization.

You would provide us with 3 young (2 to 6 month old) healthy males which have been previously proved to be fertile. We obtain the sperm (the procedure requires the sacrifice of the male) and we freeze down 10 sperm aliquots per male. The frozen specimens are maintained in the liquid nitrogen tanks of the transgenic mouse facility.

This service comprises the assessment of quantity and quality (motility) of the sperm before and after freezing, and the test of the functionality (fertilization rate) of one random frozen/thawed sperm sample per line by in vitro fertilization (IVF). Moreover, we transfer the 2-cell embryos obtained by IVF to recipient females, in order to generate alive pups. Only when we see litters born we would consider the line successfully cryopreserved.

Please do not hesitate to contact us if you have any questions regarding this technique or the form.