Since the embryos are protected from pathogens through zona pellucida, embryo transfer is considered as the easiest way to reconstitute a pathogen-free mouse colony.

Our Facility generates live mice by performing surgical transfer of embryos recovered from a cryopreserved stock (kept into our CryoBank or imported) or from fresh embryos collected by us.

Cryopreserved embryos

If the cryopreserved line belongs to our Cryobank, 40-50 frozen embryos are thawed, recovered and transferred into pseudopregnant females.
For lines to be imported the Facility arranges all transfer details, receives the embryos and performs the aforementioned procedure to revive the requested mouse line.

Fresh embryos

This service can apply in the newly imported mice kept temporarily in the Quarantine as well as Fleming mice that need to get established in a different microbiological status (SOPF mice).

The investigator provides a minimum amount of 3 male studs in reproductive age. According to the number of available male studs, an equal number of wild type females is superovulated and set up for mating. In case that the investigator requires mutated female mice to be used, he has to provide the required amount of females at the age of 4 weeks. The embryos are recovered at the 2-4 cell stage and transferred into pseudopregnant female mice.

Upon births the investigators takes tail biopsies and screens for carriers. Another round is performed if no positive mice are produced in the first round.

All live mice supplied by this service, have a specific-pathogen-free (SPF) status according to top FELASA guidelines.