The rederivation of mouse lines through embryo transfer is used to establish Specific Pathogen Free (SPF) mice from mice of any compromised health status. Pre-implantation embryos are transferred into pseudopregnant females in an SPF facility.

The efficiency of a rederivation will depend on the individual strain, especially the robustness and fecundity of the strain. Usually inbred mice will yield less viable embryos than a hybrid/outbred strain.

Embryos used for rederivation are produced via IVF.

Excess embryos from the IVF after the embryo transfers will be cryopreserved.

  • The number of times TASQ will need to perform a rederivation will vary greatly between strains. The major factors in the success of the rederivation are the age of the females, the strain background and the fertility of the males.

  • Females to be used must be aged between 8 and 16 weeks. At this age the females are more receptive to the superovulation regime, therefore producing more viable eggs.

  • Males must be over 8 weeks of age. Proven fertility is preferred but not necessary.

  • For one round of IVF, a minimum of 8-10 females  and 2 males are required.

  • If these numbers are not available, please contact TASQ for consultation for a different strategy.

  • Wild type females can be purchased on the researcher’s behalf at an additional cost.