IN SCIENCE
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Minimising the Harm Done to Animals Used in
Science
The Three Rs
Animal-based
scientists are required by law to make sure that they keep any
pain, suffering or other harm they cause to the animals they use for research ,
teaching
and testing
as low as possible. The Three Rs Principle is
applied at the planning stages before any direct work with animals
begins. Its purpose is to help scientists to minimise the invasiveness,
unpleasantness or noxiousness of anything they do to animals. The Three Rs Principle is a practical guide to
scientists. It is designed to ensure that:
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animals which might suffer are only used
when necessary (Replacement),
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that no more and no fewer animals are used
than are required to achieve the objectives of the work (Reduction),
and
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that if any noxiousness is caused during the
work, it is kept as low as possible (Refinement).
Click on the following headings to find out
more. Even more information can be obtained within each section by
clicking on highlighted words.
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The Three Rs - Replacement,
Reduction and Refinement
Replacement means that animals should not be used at all
if the same research, teaching or testing aim can be achieved in other
ways. The word "animal" refers to those higher order animals that are capable
of suffering or feeling pain. So the first question scientists must ask
themselves at the planning stage of a study is "Do
I need to use higher order animals at all?"
If the answer is "Yes" then Reduction and
Refinement must be applied.
Reduction means keeping the number
of animals used to the minimum necessary to achieve the research,
teaching or testing purposes of the work. This avoids using
unnecessarily large numbers of animals. But it is equally important to
avoid using too few animals. If not enough animals are used it will not
be possible to interpret the results, and the animals used would have
been wasted. So the second question scientists must ask is "What is the lowest number of animals needed for this
work?"
Refinement refers to keeping any
pain, suffering or other harm which may be caused as low as possible
for each and every animal used in the work. This means that every
aspect of the work must be reviewed carefully and great care taken to
minimise any noxious effects on the animals. Thus, the third question
scientists must ask is "How can I minimise the
noxiousness of every aspect of this work?" It is worth
noting that many studies cause very low or no pain, suffering or other
harm to the animals involved, while others do indeed have noxious
effects.
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Assessing the
invasiveness, severity or noxiousness of a scientific manipulation
The invasiveness, severity or noxiousness of any
proposed research, teaching or testing procedure must be given very
careful consideration during the planning stages of the work, for two
reasons.
First, it is necessary to anticipate the
extent of pain, suffering, distress or lasting harm that might be
caused to the animals by each part of the proposed procedure, in order
to work out the best ways to keep any noxiousness as low as possible
using refinement strategies.
Second, it is necessary to balance the
expected levels of noxiousness against the anticipated benefits of the
work in what is called a Harm-Benefit
Analysis. The aim of this is to make sure that any harm is the
lowest that is practically feasible and that the benefits are the
greatest that can be reasonably achieved. The benefit must outweigh the
harm by the greatest feasible margin for the work to proceed. It is the
responsibility of both the animal-based
scientists who prepare each research, teaching and testing proposal
and the Animal Ethics
Committee that reviews it to do harm-benefit analyses.
Noxiousness Scale
To help with this process
various invasiveness, severity or noxiousness
scales have been developed world-wide. These help
animal-based scientists work out what the negative impact of a proposed
procedure is likely to be on the animals. A noxiousness scale devised
and used in New Zealand recognises five grades of severity, ranging
from no or virtually no noxiousness, to very high noxiousness.
Note that the higher the noxiousness of a
procedure, the greater the anticipated benefits must be before it can
be approved. For specific examples at each level of noxiousness click
on the relevant grade.
Grade O
No suffering or noxiousness.
Such procedures would not usually require
justification in terms of expected indirect or direct
benefits to animals, people or both.
Grade A
Little suffering or noxiousness.
Such procedures would require justification
regarding the expected indirect or direct benefits to animals, people
or both.
Grade B
Moderate suffering or noxiousness.
Such procedures would require good justification
regarding the expected direct benefits to animals, people or both.
Grade C
Severe suffering or noxiousness.
Such procedures would require strong
justification regarding the expected direct benefits to
animals, people or both.
Grade X
Very severe suffering or noxiousness.
Such procedures would require the most
exceptional justification and would be permitted only very
rarely.
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How much suffering or
noxiousness is caused by research, teaching and testing procedures in
New Zealand?
In New Zealand the vast majority of scientific
procedures produce little or no suffering or noxiousness. Nevertheless,
a significant percentage of procedures are given noxiousness ratings of
"C" or "X" despite careful
application of the Three Rs. Such work can only be undertaken if those
doing it can provide strong justification
for "C" rated procedures and the most
exceptional justification for "X" rated procedures (see Balancing Harm and Benefit). A detailed
breakdown of these figures is available from the National
Animal Ethics Advisory Committee.
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