32
2. Reduction
Are the following aspects clearly explained and addressed?
Number of animals likely to be used in the project as a whole and in individual studies/protocols within it.
How the numbers have been optimised, for example by:
taking statistical advice to optimise experimental design and statistical analyses
using the results of other similar studies to inform the approach
carrying out pilot studies to help improve the design of larger definitive studies
N.B. in some cases the number of animals used will be stipulated in a regulatory protocol
If reducing animal numbers has increased the level of harm caused to individuals, whether and how this
has been justified.
When animals are humanely killed during or after studies, whether their tissues will be shared with other
researchers, to avoid any additional use of animals to supply tissue for in vitro studies.
The box below and continued overleaf includes examples of steps that a good research team would take to
implement refinement. There should be evidence in the project application and/or discussions that such aspects
have been considered, although not all will be relevant to every project.
3. Refinement
Are the following aspects clearly explained and addressed?
Choice and source of animals
Reasons for choice of species and strain of animals: e.g. why the animals are considered most relevant
for the science, but least affected by the procedures.
Any adverse effects due to source and transport of animals to the laboratory and/or quarantine
requirements, and how these will be reduced and alleviated.
If the animals are genetically altered, whether the alteration is likely to cause adverse effects and, if so,
how these will be reduced and alleviated.
Animal housing and care
How animal housing and care has been refined, so as to minimise adverse effects and provide a stimulating
environment that enables the animals to express their normal behaviours (see also chapter 7).
Any special housing and care requirements required by the procedures (e.g. confinement of animals in
'metabolism cages' that allow collection of the animals" faecal and urine output), their likely adverse effects,
and how these will be reduced and/or alleviated.
If social animals are to be housed singly at any time: why this is considered unavoidable for scientific or
welfare reasons; and how adverse effects will be reduced.
N.B. if single housing is unavoidable, action should be taken to mitigate the effects e.g. by additional
enrichment or, if appropriate for the species and individuals concerned, the animals should be housed within
sight, sound and smell of their conspecifics.