Rederivation is a service of converting valuable transgenic lines into Specific Pathogen Free (SPF) status.
The embryos from animals, which are carrying or suspected of carrying pathogenic agents are removed and transferred into pathogen free animals. The embryo transfer method is the only one, which guarantees the removal of adventitious agents (viral, bacterial and parasite contamination) from your colony giving you pathogen free animals to work with.
The client provides mice/rats in question (males or females). In standard procedure we re-derive heterozygotes, using transgene 2-6 month old, sexually mature of known age and previously successfully bred males and 6-8 females (at 6-8 weeks old age). The homozygote rederivation is also possible. In this case 3-5 transgene males and 6-20 transgene females should be provided.
After hormone-induced superovulation and mating, females are sacrificed and embryos are transferred into foster mothers (CD1). The tissue fragment from offspring will be delivered to client for genotyping.
Clients must supply the following:
- Completed rederivation protocol (Rederivation_protocol_2018.pdf)
- At least 3 males of the strain to be rederived
- At least 6 (prefer 8) females (for homozygote rederivation)
- For rederivation from the frozen embryos the Investigator provides at least 100 frozen embryos
The core performes maximum 3 sessions.
If the males provided fail to mate after 2 attempts, the investigator will be notified.
If the foster females fail to deliver live pups, the process will be repeated at no additional cost (other than the cost of more female egg donors, if needed). The investigator must inform the facility if the strain exhibits any severe defects or lethality, so that the pups can be properly monitored.
If the foster females fail to deliver pups of the proper genotype, the process will be repeated at no additional cost (other than the cost of more female egg donors, if needed) AFTER the investigator has done appropriate genetic testing on the 'dirty' animals to confirm their genotype.
If the investigator has not contacted the facility with the results of the genotype by weaning, all the pups will be transferred to the investigator's protocol number and account.
If the rederivation fails, the process will be repeated at no additional cost.
Submission form can be sent together with animals, as well as scanned and e-mailed in advance.
Do not hesitate to contact us for any questions: