Skip to main content

International 3Rs Prize now open for applications. £30k prize (£2k personal award) for outstanding science with demonstrable 3Rs impacts.

NC3Rs | 20 Years: Pioneering Better Science
Guidance

Minimising the use of GA mice

Strategies to minimise the number of mice used in the process of generating, breeding and maintaining GA mouse colonies.

Search the subject specific and specialist databases to see if the GA mouse already exists.

The phenotype observed is heavily dependent upon background strain. It is important that the genetic integrity and provenance of the wild types used to breed with GA lines are scrutinised. 

Archiving of GA lines as frozen embryos or gametes should be routine part of scientific programmes that produce GA animals. This not only helps reduce animal use by minimising the number of GA lines maintained on the shelf, but also facilitates the sharing of GA lines between researchers, providing further opportunities for reduction. A free archiving service is provided by the MRC Frozen Embryo and Sperm Archive

Read our guidance on re-establishing colonies after a pause (e.g. COVID-19 lockdown) with an emphasis on minimising the number of mice used.

White icons of three mice on a blue background. Two female mice on the left hand side are each crossed with the same male mouse on the right side, indicating how different mice can be paired for optimised breeding.

High level guidance offering opportunities for reduction and refinement, including databases and repositories for GA strains.

A black mouse in a plastic cage, standing on paper nesting material.