2. Animal model :
is a living, non-human animal used during the research and investigation of human disease,
for the purpose of better understanding the disease without the added risk of harming an
actual human being during the process.
•
• The animal chosen usually meets a determined taxonomic equivalency to humans, so as to
react to disease or its treatment in a way that resembles human physiology as needed.
• The use of animal models allows researchers to investigate disease states in ways which
would be inaccessible in a human patient, performing procedures on the non-human
animal that imply a level of harm that would not be considered ethical to inflict on a
human.
• Many drugs, treatments and cures for human diseases have been developed with the use
of animal models.
Animal models
serving in
research may
have an
existing inbred induced disease
injury that is
similar to a
human condition
3. Homologous
animals:
same causes,
symptoms and
treatment options as
would humans who
have the same
disease
Isomorphic
animals:
share the same
symptoms and
treatments
Predictive
Animals:
when animals strictly
display only the
treatment
characteristics of a
disease. This method
is commonly used
when researchers do
not know the cause
of a disease.
4. The choice of an animal depends on its suitabilityfor attaining a particular researchgoal
a) If large amounts of antiserum are sought, rabbit, goat, sheep, or horse might be an
appropriate experimental animal.
b) If the goal is development of a protective vaccine, the animal chosen must be susceptible
can be mouse, rabbit
c) But if growth of the infectious agent is limited to humans and primates, vaccine
development may require the use of monkeys, chimpanzees, or baboons
5.
6. Mouse Lifespan: 1-3 years
Gestation: 21 days
Weaning: 21 days
Sexual maturity
Females: 6 weeks
Males: 8 weeks
Estrus: 4-6 days
.
7. Gestation: 21 days
Weaning: 21 days
Estrus: 4-6 days
Sexual maturity
Females: 6 weeks**
Males: 8 weeks
Lifespan
2-3.5 years
10. Mustela putorius furo
Stinky little thieving weasel
Illegal in California
“Nail” trims
Use small nail-trim scissors or human nail clips.
Blood collection: use chemical restraint
Sample sites
Jugular vein
Cranial vena cava—preferred
Cephalic vein
Long-gestation period
Precocious young
Open-rooted teeth may become maloccluded
Fastidious eaters
Grass-based commercial pellet
Vitamin C supplementation:
CANNOT SYTHESIZE THEIR OWN. Must be supplemented.
Fresh water
Footpad dermatitis
11. Hamsters live an average 18 to 24 months
and have a gestation period of 16 days.
Active burrowing animals adapted to desert environment.
Life span 3.5 years
Prone to autogenic seizures
Good at escaping
Diet similar to hamster
Nasal dermatitis
Tyzzer’s disease caused by B. piliformis
Never grab gerbil tails: DEGLOVING INJURY
12. a) The closest to humans –
mammal
we share virtually ALL of our genes and use them in similar
ways
b) The most complex -
integration of systems (endocrine, immune, nervous etc.)
c) ability to quickly multiply,
reproducing as often as every nine weeks. generation time is ~ 3
months, so genetics can be done
d) Easy to handle
mice are ~ 3 inches long, can keep many mice in a room.
13. Three main concerns regarding the use of any lab or exotic animal:
Risk Preventation measures
Allergies Personal Protective Equipment (PPE)
Occupational Health Surveillance Program
Through Sanitation
Injury PPE
Proper Handling (Confident handlers!)
Zoonotic Disease PPE
Through sanitation
Occupational Health Surveillance Program
14. Animals are used to understand basic biology, as “models” for studying human biology
and disease, and as test subjects for the development and testing of drugs, vaccines,
and other biologicals (i.e. antibodies, hormones, ingredients in vaccines, etc.) to
improve and advance human health.
The use of genetic engineering—manipulation of an animal’s DNA or genes—is
prevalent throughout many fields of research, particularly biomedical. “The mouse has
become the flagship of animal testing, especially useful with genetic modifications,
gene knock outs [genes are removed], and knock ins [genes are added].
In 2003, NIH [National Institutes of Health] launched the Knock out Mouse Project and
has awarded more than $50 million with the goal of creating a library of mouse
embryonic stem cells lines, each with a gene knocked out.”
15. animals are subjected to invasive procedures, which can include :
Surgeries , traumatic injuries , burns
, force-feeding , blood draws , biopsies
, Food , water , and social deprivation
, dart gun sedation , prolonged restraint , viral and bacterial infections
, behavioral and environmental manipulations, and exposure to toxic drugs and chemicals.
Examples include, “creating heart attacks, heart failure, abnormal heart rhythms,
strokes, and other cardiovascular traumas in monkeys, dogs, pigs, and other animals;
inducing symptoms of migraines in cats and primates through brain stimulation and
manipulation with chemicals; implanting electrodes into the intestines of dogs to induce
motion sickness and vomiting; implanting electrodes into the brains and eyes of monkeys
and cats to conduct neurological and vision experiments; and dropping weights onto
rodents to produce spinal cord injuries and paralysis.
17. Animal models for CNS activity
Animal models to evaluate Muscle relaxant activity
Model to evaluate CNS depression & sedation
Animal models for anti-anxiety activity
Anti-convulsant & Anti-epileptic animal models
Analgesic animal models
18. Rabbit’s sensory system may be studied in basic research; she may be used as a model for
eye and skin disorders, or used in eye and skin irritancy tests for environmental toxicity
testing.
Dogs, typically young purpose-bred beagles, are commonly used in cardiovascular studies,
heart and lung research, genetic studies, age-related research, pulmonary studies, cancer
research, and orthopedics, such as the development of prosthetic devices for hip and knee
replacements, vertebral fusion models, cervical disc degeneration, etc.
Cats “have long been a mainstay of nih-funded studies of neurological, cardiovascular, and
respiratory diseases, and the immune system.”Researchers also use cats in cancer research,
genetic disorders, and eye, ear, and infectious disease research.
Nonhuman primates are used in research on vaccines, infectious, cardiovascular, and
neurological diseases, aging, reproductive biology, gene therapy, drug addiction,
xenotransplantation (cross-species transplants), and vaccine and toxicity testing. The two
most common primate species used by far are rhesus , chimpanzees and cynomolgus
macaques.
Guinea pigs and hamsters, who are both used a great deal in toxicity testing and as models
for infectious, cardiovascular, and neurological diseases, and drug abuse research.
Both mice and rats are heavily used in vaccine and drug research and testing.
Birds are used in research on organ development and deformity, visual impairment,
muscular dystrophy, and nutrition, among other things.
For example :
19. Millions of animals and taxpayer dollars are used in the production and testing of
biologicals, such as vaccines and antibodies.
For example, a complete batch test for a therapeutic protein can involve 12,000 mice
and cost $2.4 million; 2007 estimates for the cost of drug development and to bring it to
market range from $800 million to $1.7 billion.
Potential drugs are often required to be tested in at least two animal species in preclinical
trials before moving on to human clinical trials.
Yet “only around 5% of drugs that show potential in animal studies ever get licensed for
human use.”
Potency tests of such products as vaccines are still based routinely on the principle of
protection, i.e., survival or death after exposure, which was first introduced in the 1890s.
Many of these tests are exceptionally cruel, involving high levels of pain and distress for a
range of species from rodents to nonhuman primates (including chimpanzees).