2. Introduction
History of Animal Experimentation
• Classical Antiquity (between 8th century BC and 6th century
AD):
• Aristotle’s animal observations laid the basis for
comparative anatomy & embryology
• Erasistratus: identification of veins, heart, valves and
understanding blood flow
• Galen: principles for experimental research (vivisection)
• Little advancement during the Middle Ages
• Renewed interest during the Renaissance period (e.g. W.
Harvey)
• Significant number of major medical advances during
the second half of the 19th century (use of anesthetics)
• 1950’s beginning of laboratory animal sciences as a
separate field of expertise
• Since 1970’s decline in numbers of animals used
8/29/2023 2
3. Introduction Cont’d
Is animal-based research is acceptable?
In discussing animal-based research one needs to
distinguish:
• Ethical issues
• Scientific issues
• Legal and regulatory issues
8/29/2023 3
4. Introduction Cont’d
Ethical issues
Is it permissible for one species to cause pain, suffering
and death to another to achieve aims that benefit primarily
the former species?
Do we have ethical obligations to non-human animals ?
What kind of use or treatment of non-human animals is
ethically permissible or required?
Laboratory animals:
• Developed nervous system
• Cannot consent
• Generally do not benefit
• Capable of suffering
8/29/2023 4
5. Introduction Cont’d
Animal welfare
Utilitarianism
J Bentham (1742-1832) / JS Mill
• The question is not ‘Can they reason? Nor ‘Can they
talk? But ‘Can they suffer?’
• Cost-benefit analysis
• The largest benefit/happiness
• Minimize suffering
• P. Singer
Speciecism
• Equal consideration of ‘sentient’ species
• Pain is pain -> animal = human
• Pain, distress, suffering of non-human animals should be
minimized
• While we have duties/rights to animal welfare, animals
do not have rights
8/29/2023 5
6. Introduction Cont’d
Animal welfare comprises the state of the animal’s body and
mind, and the extent to which its nature (genetic traits manifest
in breed and temperament) is satisfied
Concept of 5 F’s
• Freedom of
• Thirst and hunger
• Pain, lesions, disease
• Discomfort
• Expressing natural behavior
• Fear, distress
8/29/2023 6
7. Introduction Cont’d
Animal rights
If animals cannot consent to x, humans cannot do x without
violating the animals’ rights
Rule of thumb: if you could not do x to a human infant,
you cannot do x to an animal
Animals have an intrinsic value and thus rights (T. Regan)
Animals have the right to not suffer (suffering is a
reduction in the capacity to fulfill needs/desires).
Sentient animals should not be used as instruments in
the pursuit of human goals
Sentience is the capacity to perceive or feel things.
Cost-benefit analysis is irrelevant
Total abolishment of the ‘use’ of animals
8/29/2023 7
8. Introduction Cont’d
Society’s view on animal-based research
• Some people committed to animal welfare
• Some people committed to animal rights
• Some people neither committed to animal welfare nor
animal rights
• What is your opinion?
8/29/2023 8
9. Introduction Cont’d
Scientific issues
• Learning about non-human animals themselves
(translational research, comparative approach, etc.)
• Use of animal models to answer question on human
(and animal) health
Does the scientific use of animals lead to valid, useful and
relevant results in specific areas?
advancing scientific knowledge (basic research)
using animals as models for humans to study disease
mechanisms and develop interventions
animals as models in toxicity testing
8/29/2023 9
10. Introduction Cont’d
Basic research can be argued that data produced are valid
insofar as it is conducted in a methodologically sound
manner, since any such completed research project adds to
the scientific body of knowledge
The question of validity, usefulness and relevance is more
complicated when animals are used as models for humans,
as the question of whether reliable extrapolations can
actually be made from one species to the other, needs to be
addressed.
there are researches that used animal models where it has
been possible to make valid and useful inferences
Example: Narcolepsy, Myasthenia gravis
8/29/2023 10
11. Introduction Cont’d
claims that the very concept of using animals as models for
humans is flawed, misleading and dangerous because a small
number of products such as medicines that have involved
animal research and testing in their development were
withdrawn from the market because of adverse reactions in
people
Example: Thalidomide‐induced teratogenesis
8/29/2023 11
12. Introduction Cont’d
Because of evolutionary continuities in the form of
behavioral, anatomical, physiological, neurological,
biochemical and pharmacological similarities between
animals and humans there are sufficient grounds for the
scientific hypothesis that, in specific cases, animals
can be useful models to study particular aspects of
biological processes in humans, and to examine the effects
of therapeutic and other interventions
The scientific validity of animal experiments is a condition
capable of being fulfilled, but has to be judged case by case
and subjected to detailed critical evaluation
8/29/2023 12
13. Introduction Cont’d
Two commonly encountered wrong generalizations about
research involving animals that is undertaken with the aim of
yielding results that are applicable to humans:
i) all such research is directly applicable to humans
ii) no animal research has ever produced results that are
useful and relevant to humans
8/29/2023 13
14. Introduction Cont’d
Legal and regulatory issues
• Legislation
• National
• International: European
Example: 2010: European directive 2010/63/EU
• Accepts the use of laboratory animals for research
purposes
• 3 R’s concept strongly embedded focusing on
refinement
8/29/2023 14
15. Introduction Cont’d
• Regulatory rules
• Ethical committee on animal experimentation
• Institutional, national, regional …
• Prior to starting up an experiment, an approval is needed from
this committee
Composition of Ethical committee on animal experimentation:
• Experts
• Researchers
• Lay-men
• Government representative
8/29/2023 15
16. 3 R’S concept
The three R’s principle addresses harm reduction through
three approaches:
1) the replacement of animal research with alternative
animal-free methods
2) the reduction of the number of animals used
3) the refinement of methods to minimize the distress
caused to animals used in research
8/29/2023 16
17. 3 R’S concept cont’d
The replacement principle
If it is possible to obtain scientific benefits without using
live animals, we should do so
using experimental procedures that do not involve live
animals, such as in vitro (e.g., cell lines), ex vivo (e.g.,
tissue culture), computer/in silico (e.g., bioinformatics),
embryonic / larval form , and non-vertebrate model
methods in place of existing procedures using animals
8/29/2023 17
19. 3 R’S concept cont’d
The reduction principle
In animal studies that involve harm, the use of fewer animals
will normally cut collective animal suffering (sample size)
reduction has other benefits, it is good resource
management; laboratory animals and their housing and
care are costly
Re-use
Reporting negative data
on the other hand, reduction may have an adverse impact;
using too few animals to produce meaningful results is as
unethical as using more animals than necessary
8/29/2023 19
20. 3 R’S concept cont’d
The refinement principle
This urges to minimize any pain or distress that will be
caused by experimental procedures
To adapt experimental procedures so that they cause
less pain or distress
Cage enrichment
Use of anesthetics, analgesics
In vivo imaging
Using humane end points
8/29/2023 20
22. Animals Used in research
Differences in national statistics (number of animals used)!
• (Animals killed for ex-vivo experiments)
• Genetically-modified animals used solely to maintain
established breeds
• Animals killed as surplus
• (Certain invertebrates i.c. cephalopods)
• Observational studies
• Fish tagging and other environmental studies on wild
animals
8/29/2023 22
29. Assignment
1) Anesthesia and Euthanasia in animal experiment
Experimental Procedures
1) Administration of drugs or other substances in
animal experiment
2) Collection of blood, urine, feces in animal
experiment
8/29/2023 29
