Embryo Transfer Rederivation

Mouse known to harbor pathogens are not allowed in the SPF facility of the Rockefeller University. Rederivation of mouse lines infected with various pathogens allows housing of the lines in pathogen-free facilities. Rederivation is the process whereby fertilized embryos are isolated from donor females mice and transferred into foster mothers free of disease and raised to term.

Procedure Outline

1. The Investigator should submit the Rederivation Request Form to CBC and the Transgenic and Reproductive Technology Center.
2. Prior to being rederived, animals imported from donor institutions will be placed in short duration quarantine (only one testing will be performed). Animals which are housed in CBC should also be tested. The Investigator should submit the Serology Requisition Form. After results come back negative for all tested pathogens, the Investigator submits the Transfer Request and the animals will be transferred to room 229.
3. At least 3 proven breeders males are requested for rederivation.
4. Females of 4 weeks old should be provided/purchased by the Investigator.
5. Transgenic Services personnel will superovulate egg donors, set up matings, recover eggs and surgically transfer fertilized eggs to SPF pseudopregnant foster mother.
6. The Transgenic Services staff will wean 3 weeks old pups and submit foster mothers for blood serology. Upon receiveing negative results for all tested pathogens, pups will be released into the Investigator’s room.
7. Tail tipping can be performed at the Investigator’s request for an additional charge of $40 by Transgenic and Reproductive Technology Center personnel or ordered by the Investigator through CBC services.
8. The Investigator is responsible for timely reporting of genotyping results to the Transgenic and Reproductive Technology Center. If results are not reported on time (2 weeks), all cages with litter will be transferred into the Investigator’s room.

In cases where in order to maintain certain genetic marker rederivation should be done using investigator’s females, the standard fee will be assessed even if the rederivation attempts fail.