Breeding and colony management

Are you returning to animal research following the COVID-19 lockdown? You may be facing specific challenges related to the management of genetically altered (GA) mice colonies after the significant interruption enforced by lockdown, such as:

  • Breeding experimental cohorts from a colony that was dramatically reduced in size during lockdown.
  • Completing animal experiments that were started before lockdown.
  • Rapid generation of animals of a specific age or sex is required.
  • A complex strain needs to be bred (e.g. condition allele expression) but one of the intermediate strains is not available.

To help address these challenges and more, the NC3Rs convened an expert working group to provide guidance for researchers and colony managers. The working group included experts in breeding, archiving, colony management and experimental design from academic and commercial organisations.

This resource will guide you through a number of different post-lockdown GA mouse breeding scenarios and outline different breeding and experimental design strategies to optimise the use of available animals and minimise surplus animals. This resource also includes guidance on how to take the opportunity presented by a return to animal research after an interruption to apply best practice. This best practice guidance covers critical aspects of breeding, colony management and archiving of GA mouse strains, including:

  • The importance of confirming genotype.
  • Establishing reproductive characteristics and keeping accurate records.
  • Why, when and how to archive a strain.
  • Avoiding genetic drift.
  • Importance of genetic background.
  • Choosing a breeding strategy based on genotype (e.g. backcross vs intercross) and timeframe required (e.g. intermittent breeding when no immediate experiments planned, trio matings to expand experimental cohorts).

Although the guidance is based on mouse colonies and experiments, the principles apply to other species.