Animals in SPF breeding units ('x week rule')
Capacity issues at the SPF sections can make it necessary for AEM to introduce a rule that limits unintended housing of mice at SPF sections 10-2 and 10-4.
The rule implies that there must be a plan for what should happen to the animals as soon as possible before they are x weeks old i.e. whether they should be:
- Kept in the breeding sections - for new breeding or as back up for the breeding
- Transferred to a particular experimental section
- Transferred to cryopreservation (contact the Core Facility for Transgenic Mice)
- Euthanized
Likewise, the results from genotyping must be returned to the relevant SPF section within x weeks.
The value of x will often be 12 weeks of age.