1. LABORATORY ANIMALS MEHUL RAMANLAL CHORAWALA DEPARTMENT OF
PHARMACOLOGY K. B. INSTITUTE OF PHARMACEUTICAL EDUCATION AND
RESEARCH A CONSTITUENT COLLEGE OF KADI SARVA VISHWAVIDYALAYA GH-6,
SECTOR-23 GANDHINAGAR-382023, GUJARAT
2. Commonly used lab. animals Kingdom: Animalia Phylum:
Chordata Class: Mammalia Most widely used: Mammals: Monkey,
baboons, chimpanzees, cat, dog, ferrets, shrew , gerbil, guinea
pig, rat, mouse, oppossum, mice Other less widely used: Birds,
reptiles, amphibians, fish, shark Almost all lab. Animals belong to
mammalia class
3. Definitions Primates: Any member of the biological order
Primates, group that contains all lemurs, monkeys, and apes,
including humans. Carnivores: derives its energy and nutrient
requirements from a diet consisting mainly or exclusively of animal
tissue, whether through predation or scavenging. (meat eater)
Animals that depend solely on animal flesh for their nutrient
requirements are considered obligate carnivores while those that
also consume non-animal food are considered facultative carnivores
. Insectivores: type of carnivore with a diet that consists chiefly
of insects and similar small creatures.
4. Lagomorpha Chordata Definitions
5. Definitions Rodents: Rodere meaning gnaw. two continuously
growing incisors in the upper and lower jaws which must be kept
short by gnawing. 40 % of mammal species all continents other than
Antarctica. include mice, rats, squirrels, porcupines, beavers,
chipmunks, guinea pigs, and voles. sharp incisors that they use to
gnaw wood, break into food, and bite predators. Eat stored food and
spread disease
6. Difference between Lagomorpha & Rodentia Lagomorpha
Rodentia four incisors in the upper jaw Almost wholly herbivorous
Male's scrotum is in front of the penis Penis contains no bone
(baculum) teeth grow throughout their life, thus necessitating
constant chewing to keep them from growing too long. E. g rabbit,
hare Two in the Rodentia Many eat both meat and vegetables Male's
scrotum is behind the penis Penis contains bone (baculum) teeth
grow throughout their life . E. g mouse, rat, guinea pig
7. Animals Rodents: Rat (Rattus norvegicus) Mouse (Mus
musculus) Guinea pig (Cavia porcylus) Gerbil () Hamster ()
Didelphimorphs Opossum () Insectivores Least shrew (Cryptotis
parva) Asian musk shrew (Suncus murinus) (vomits-CTZ ab.-Other
brain area involved )
9. Biological names Genus and species followed by variety
Genus: Species: Breed: Strain: Variety: Breed and strain are from
the same species.
10. Species Almost all domestic pet rats and lab rats belong to
a single species, the Norway rat (Rattus norvegicus). Wild black
rats (Rattus rattus) rattus & norvegicus are species 66 species
within genus : Rattus
11. Strain Group of individuals which share a presumed common
ancestry and have clear-cut physiological but not usually
morphological distinctions Rat strains -- laboratory rats that have
been bred in isolation for generations. A rat strain is created
through breeding Similar to each other and can therefore be used in
research. E. g Wistar, Fisher, and Sprague Dawley, and their
hundreds of internal divisions
12. Breed A type of animal that differs from all others of the
same species in some way, has a separate history and breed name,
and has been breeding true for a number of generations. Beagle and
Doberman are examples of different dog breeds. 1,000 dog breeds No
separate breeds of rats
13. Breed Vs strain Overlap between the two terms Both refer to
subgroups of individuals in a given species which share common
traits due to common descent. Strain physiological differences
Breed morphological differences. Physiological differences
differences in physical and chemical function, and therefore are
often internal and invisible. E. g a high resistance to cold or
heat, a blood clotting disorder, an immunodeficiency, high milk
yield (cows), strong wool (sheep) Morphological differences
differences in form or function, and therefore tend to be external
and visible. E. g body size, leg length, coat color, coat length,
tail length, head shape, and ear placement.
14. Variety Pet rats are quite variable in appearance e. g
different colors and markings Fur: straight or wavy or without fur
Ears: may be low-set Tails: long or short or absent Rat variation
is loosely divided into varieties or types (e.g. RMCA and AFRMA). A
variety : group of rats that share a single physical trait. E. g
rats with curly fur belong to the "rex" variety, rats with low-set
ears are called "dumbo," rats without hair are called "hairless."
Single rat may belong to more than one variety, such "dumbo" and
"rex." A variety is therefore a purely descriptive category, it
says
15. Varieties in rats All rats are shown in six Varieties:
STANDARD With short, smooth, glossy hair REX With curly hair and
curly whiskers TAILLESS Complete absence of a tail HAIRLESS
Complete absence of hair SATIN Thinner, longer coat, with a
lustrous sheen DUMBO Larger ears set on the side of the head
16. Varieties in rats (Rex)
17. Varieties in rats (Rex)
18. Varieties in rats (Dumbo Rat)
19. Varieties in rats (Satin Rat)
20. Satin Rat (Ivory)
21. Inbred strain Defined as a product of over 20 generations
of brother-sister matings, which results in individuals that are
98% identical to each other. After 40 generations of inbreeding,
they are 99.5% similar. In other words, they are almost clones. At
this stage, the inbreeding coefficient should be 0.99 (i. e,
residual heterozygosity approximately 1%). Animals of the same
strain and sex are homozygous and genetically very similar. The
assumption that all sources of the same inbred strain provide
genetically identical animals is not valid, as animals maintained
at different institutions for many generations may show genetic
drift, even though they originate from the same source.
22. Inbred strain Advantage remain genetically stable over a
long period of time. However, it is important to be aware that the
use of inbred strains depends on the nature of the experiments.
Disadvantage Constant monitoring of the genetic stability of an
inbred strain is required. Each of them represents a very narrow
selection of the wide and functional genetic variation observed in
a wild population. The use of at least two inbred strains is often
preferable when toxicity studies are extrapolated to human
population.
23. Substrains They are subdivisions within a strain of rats.
Substrain with an established genetic difference, the substrain of
Zucker rats (Lois M. Zucker and Theodore F. Zucker, pioneer
researchers in the study of the genetics of obesity.) Leptin
receptor in hypothalamus (satiety) Zucker -- Faulty leptin
receptors. Leptin can't bind to the faulty receptor, so Zucker rats
never feel full. Eat constantly and become morbidly obese As models
for obesity, diabetes and heart disease
24. Zucker Fatty Rat
25. Diabetic Zucker Rat
26. Outbred Strain Genetically heterogeneous and are often
produced by breeding systems that minimize inbreeding. Random
pairing is best planned with the aid of tables of randomized
numbers or a randomizing device.
27. Outbred Strain Disadvantages each breeding colony may be
different due to genetic drift. Wistar or Sprague - Dawley rat from
one breeder may be genotypically and phenotypically different from
those obtained from a different source. Considerable differences in
neuroanatomy, behaviour and pharmacology have been reported, for
example, in Sprague - Dawley rats obtained from different
commercial breeders.
28. Stock Vs Strain The term stock is used to denote an
outbreed population of mice while the term strain is used to denote
an inbred population. Defined as an outbreed when it has been
maintained as a closed colony for at least four generations. To
minimize changes caused by inbreeding and genetic drift, the
population should be maintained in such numbers as to give less
than 1% inbreeding per generation.
29. Rattus Rattus contains 66 species Rattus norvegicus or
brown Norway rat Rattus rattus or black rat The two species differ
considerably in their habitats, behavior and ecology. Wild Rattus
norvegicus has agouti -coloured fur- - has agouti gene which
produces hairs with colour bands varying between brown black and
red yellow. Rattus rattus may have a more variable coat colour, but
is mainly dark brown or black. R. norvegicus lives mainly in burrow
systems at ground level, whereas R. rattus tend to occupy higher
areas in trees and roofs.
30. History of the Norway Rat (R. norvegicus) The first
laboratory rats: Albino rats (actually spontaneous mutation was
seen) were brought into laboratories for physiological studies as
early as 1828. First breeding experiments in the 1870s and 1880s
White rats of European origin were brought to America shortly after
this and became the foundation stock of American laboratory rats
The oldest strain of inbred rats dates from 1856. The oldest
purpose-bred strain of inbred rats, the PA strain, had been created
by Helen Dean King at the Wistar institute in Philadelphia by 1909
. The Wistar rat, and to a lesser extent, the Sprague- Dawley rat,
gradually became the most popular rat strains for laboratory
research.
31. Laboratory rat A laboratory rat is a rat of the species
Rattus norvegicus which is bred and kept for scientific research.
Laboratory rats have served as an important animal model for
research in psychology, medicine, and other fields.
32. Comparison and contrast between RAT : Wistar and Sprague
Dawley Strains Common name : Rat Scientific name : Rattus
norvegicus Strain : Wistar and Sprague Dawley Source: Denmark Coat
color: Albino
33. Comparison and contrast between Wistar rats wider head,
long ears, and the tail length always shorter than that of the body
length. Sprague - Dawley rats longer and narrower in head , longer
tail, which may equal or be longer than the body length. Wistar
rats are more active than Sprague Dawley rats
34. Strains of lab. rats Albino Wistar : Developed at the
Wistar Institute in 1906. Easy to handle and male aggressive
behavior develops relatively late. An outbred or random - bred
strain and a large number of varieties exist worldwide.
35. Strains of lab. rats Albino Sprague - Dawley : Originated
by R. Dawley, Sprague-Dawley Company, Madison, Wisconsin, in 1925.
Now purchased by Harlan Sprague Dawley Originally female albino
Wistar rats were crossed with hybrid hooded males from an unknown
origin. and subsequently to his white female offspring for seven
successive generations. Multiple lines, developed by inbreeding,
thereafter were outbred to develop a stable, heterogeneous stock.
Calmness and ease of handling
36. Sprague dowley
37. Sprague dowley Rats
38. Strains of lab. rat Long - Evans hooded: Developed by Dr.
Long & Evans at Berkeley, California in 1910. Crossing several
Wistar females with wild gray male. Head and extremities - black or
brown Rest of the body - white with pigmented eyes easily handled
Level of aggressive behavior is generally high. Behavioral and
obesity research
39. Long Evans Rat
40. Long Evans Rat
41. Uncommon strains or substrains Apart from the traditional
inbred and outbred strains, a wide variety of genetic selection
lines are available. These lines are genetically selected for the
presence or absence of certain behavioural or physiological
characteristics. E. g Roman High Avoidance (RHA) and Roman Low
Avoidance (RLA) lines are selected for their behavioral performance
in an active shock avoidance paradigm, using the Roman Wistar as
the parental population. The Kyoto Wistar was used to select the
Spontaneous Hypertensive Rat (SHR) line, using high sympathetic
reactivity as a selection criterion. Most of these genetic
selection lines are not commercially available Can only be obtained
via the specific research institutes that breed and select these
lines.
42. Shaking rat Kawasaki Neurological mutant rat in the Wistar
strain first described in 1988: Neurological signs : shaking of the
body and an ataxic-paretic gait from day 10 postnatal. CNS:
cerebellum: small, frequently vermis and paraflocculus lacking,
malposition of the neurons in the cerebral cortex, hippocampus and
cerebellum. Abnormal myelinated fibers in the molecular layer of
the cerebral cortex and in the central gray matter of the spinal
cord. Survival : The affected rats survive for about 1 month. Genes
: short deletion in the RELN gene; Reelin, product of RELN gene is
essential for proper cortex lamination and cerebellum development.
good animal model of human congenital malformations with neuronal
migration disorders.
43. RCS rats The Royal College of Surgeons (RCS) rat The first
known animal with inherited retinal degeneration. Mutation in the
gene Mertk results in defective retinal pigment epithelium
44. Hairless rats compromised immune systems and genetic kidney
diseases Over 25 genes that cause recessive hairlessness in
laboratory rats Common : rnu (Rowett nude), fz (fuzzy) and shn
(shorn). Rowett nudes, first identified in 1953 in Scotland, have
no thymus. severely compromises their immune system, infections of
the RT and eye increasing the most dramatically. Fuzzy rats (fz/fz
rats) were identified in 1976 in a Pennsylvanian lab. progressive
kidney failure that begins around the age of one month causes
death. Shorn rats were bred from Sprague Dawley rats in Connecticut
in 1998. They also suffer from severe kidney problems.
45. Hairless rats
46. Fuzzy rats fuzzy mutation has been mapped to a location on
Chromosome 1 Homozygous infant rats have curly or twisted whiskers
at birth. First coat is short, rough, and the hairs are broken,
which gives the coat a wavy appearance. This short coat may last
through one or two hair cycles, but by 2 months of age most mutant
rats have only sparse hair and a fuzzy appearance, or no hair at
all. By six months, all homozygous rats are usually smooth-skinned
and remain so thereafter. suffers from chronic, progressive
nephrosis, or nephropathy, which shortened their lifespan to 16.6
months in males and 20.4 months in females. Males averaged 16.6
months (range: 12-20 months), and females averaged 20.4 months
(range: 17-26 months) at time of death. decreased lifespan as
compare to normal rats
47. Shorn rats The shorn locus has been mapped to a narrow area
of Chromosome 7 Shorn, a recessive mutation causing hairlessness,
was discovered in 1993. Shorn rats display a very sparse, patchy
coat throughout their lifetimes. develop abnormal hearts and
kidneys which are yellow and bumpy instead of red and smooth. tend
to be smaller than normal rats and they die prematurely, at around
12-14 months of age
48. Orthologues between rat and mouse genes causing
hairlessness Rats Mice fuzzy (fz), Charles River hairless (hr)
frizzy (fr) Rowlett Nude (rnu), New Zealand Nude (nznu) nude (Whn)
shorn (shn) -- none -- -- none -- fuzzy (fz) -- none -- hairless
(hr)
49. Biobreeding Rat (BB) Known as BB or BBDP rat is an inbred
laboratory rat strain that spontaneously develops autoimmune Type 1
Diabetes. BB rats are used as an animal model for Type 1 diabetes.
The strain re-capitulates many of the features of human type 1
diabetes, and has contributed greatly to the research of T1D
pathogenesis. Two genes have been identified - the MHC Class II
gene and Gimap5, causing a severe T cell lymphopenia. Recently, 8
further loci on rat chromosomes 1,2,3,6 (2 loci), 12 and 14 have
been shown to be linked to Type 1 Diabetes in the BB rat. Non-obese
diabetic or NOD mice, like the Biobreeding rat, are used as an
animal model for type 1 diabetes. NOD mice exhibit a susceptibility
to spontaneous development of autoimmune insulin dependent diabetes
mellitus...
50. Why rats cant vomit ? Rats have a powerful and effective
gastroesophageal barrier (1) Rats can't relax the crural sling
while contracting the rest of the diaphragm. The diaphragm has two
muscles: the crural (muscle fibers attached to the vertebrae,
called the crural sling) and the costal (muscle fibers attached to
the rib cage). For vomiting costal muscle contraction and crural
muscle relaxation required. Doesnt occur in rat. (2) they can't
wrench open the esophageal sphincter. esophageal sphincter is
opened during vomiting with the help of the longitudinal muscle of
the esophagus. Weak in rat. (3) rats lack the necessary neural
connections to coordinate the muscles involved in vomiting.
Brainstem nuclei and the muscle systems used in vomiting, rats dont
have complex connections between the nuclei or between the
brainstem and the viscera that are required for such a coordinated
behavior. E. g Rat, mouse, guinea pig, rabbit
51. Alternative to vomiting Rats do experience nausea and have
evolved an alternative to vomiting: pica, the consumption of
non-nutritive substances When rats feel nauseous they eat things
like clay, kaolin, dirt and even hardwood bedding (eating clay and
dirt is a type of pica called geophagia). Clay -- binds and
inactivates chemicals so deactivates toxins. Food avoidance
Response- First line defence Pica -- second line of defense against
toxins.
52. kangaroo rats Norway rats, kangaroo rats, and cotton rats
all look like "rats" to the casual eye, even though they have many
other subtle differences that indicate they are not as closely
related as they look. Their resemblance to each other is actually
only superficial -- they're all rodents with long tails, Kangaroo
rats are only distantly related to Norway rats. They are both
rodent species (they belong to the order Rodentia) Kangaroo rats
belong to the family Heteromyidae, while Norway rats belong to a
different family called Muridae. In fact, Norway rats are more
closely related to house mice than they are to kangaroo rats, as
both rats and mice belong to the same family Muridae.
53. Kingdom: Animalia Phylum: Chordata Class: Mammalia Order:
Rodentia Family: Heteromyidae Subfamily: Dipodomyinae Genus:
Dipodomys Kangaroo Rat
54. Kangaroo Rat
55. Characteristics of Kangaroo rat 19 species Size : 10 to 20
cm, with a tail of equal or slightly greater length Weight : 35 to
180 grams Most distinctive features: very long hind legs &
efficient kidneys. Longer loop of Henle in the nephrons which
permit a greater magnitude of countercurrent multiplication , can
produce urine up to an osmolarity of almost 6,000 mosm/liter, which
is five times more concentrated than maximally concentrated human
urine at 1,200 mosm/liter. Because of this tremendous concentration
ability, kangaroo rats never have to drink; the water produced
metabolically within their cells during oxidation of foodstuff
(food plus O2 yields CO2 + H2O + energy) is sufficient for their
body. Dont lose water by perspiring because have no sweat glands.
Can recover 90% of the loss by using metabolic water gaining the
remaining 10% from the small amount of water in their diet.
56. Kangaroo rat
57. Cotton Rat Cotton Rat Origin In 1996, Harlan obtained a
cotton rat breeding nucleus from National Institutes of Health,
Bethesda, Maryland, and Virion Systems, Inc. Any member of the
rodent having genus Sigmodon. build their nests out of cotton, and
can damage cotton crops. small ears and dark coats North and South
America primarily herbivores
58. Cotton rats are a little more closely related to Norway
rats. They belong to the same family Muridae, but cotton rats are
in a different genus, called Sigmodon, while Norway rats are in the
genus Rattus. Molars of cotton rats are S-shaped when viewed from
above (genus- meaning S- tooth). Sigmodon hispidus was the first
model organism to be used in polio research. Cotton Rat
61. Cotton Rat Characteristics Coat: color combination varies;
gray, brown, black Litter average: 5.5 New World rodent: Sigmodon
hispidus Susceptible to a wide range of human infectious disease
agents
62. Cotton rats as model of infectious diseases Adenoviral
vector-based gene therapy Infectious disease pathogenesis
Respiratory Syncytial Virus Herpes Simplex (Type 1 & Type 2)
Parainfluenza Type 3 Polio Measles Monkeypox Metapneumovirus Human
Immunodeficiency Virus Influenza Virus
63. Cotton rats as model of infectious diseases Bacterial
infections Mycobyterium tuberculosis bovis Haemophilus influenzae
Rickettsial infections Staphylococcus aureus Fungal infections
Parasitic infections
65. Hamsters Stout - bodied, stubby tailed, virtually tailless,
broad - headed, velvet-furred , cheek - pouched, burrowing and nest
building rodents. Origin: Middle East and Southeastern Europe
Commonly used: Syrian hamster ( Mesocricetus auratus ), known also
as Golden Hamster Less often used: Chinese (Cricetus griseus )
European hamsters (Cricetus cricetus ) Djungarian hamster (Phodopus
sungorus), also known as the Winter white Russian dwarf hamster,
Dzungarian dwarf hamster, Russian dwarf hamsters, Siberian hamster,
Winter white hamsters, and Sapphire winter white Russian dwarf
hamster
66. Hamsters characteristics Color and hair-type: cinnamon,
cream, white, and "teddy bear" (the long-haired variety). Unique
anatomic feature of hamster: 1. cheek pouches =pouching of the oral
(mouth) cavity on both sides, extending alongside the head and neck
to the shoulders. Use : to store food and allow the hamster to
transport food from where it is gathered to the hamster's den or
nest. The food is then eaten later, at the hamster's leisure.
Represents false appearnace of tumors or abscesses. 2. paired
glands in the skin over the flanks: Appear as dark spots within the
haircoat and are much more obvious in males than females. Glands
are used to mark a hamster's territory and also have a role in
sexual behavior.
67. Syrian/Golden hamster
68. Syrian/Golden hamster
69. Syrian/Golden hamster
70. Golden Hamster Unusual and unique features which make them
particularly useful for certain experimental studies. Immuno
genetic characteristics : marked tolerance to homologous,
heterologous and human tumours, parasites, viruses and bacteria.
Reversible cheek pouches: allow tumour grafts from other species,
including man, to grow freely and symmetrically without the need to
induce immunosuppression. Dental research: form and occlusion of
their molar teeth closely resemble those of humans and the
induction of lesions is possible without fracturing of the teeth,
as in rats. Teratology: short gestation period is advantageous
Thermophysiology and circadian rhythm studies Use of Syrian hamster
oocyte in assessing human spermatozoal fertilising potential.
Quantifying the effects of various factors affecting human sperm
function in vivo.
71. Chinese Hamster
72. Chinese Hamster with Pups
73. European hamster
74. Laboratory mouse most widely used vertebrate species in
biomedical research Adv: short reproductive cycle, Short lifespan,
small size low cost of maintenance cancer and drug research,
vaccine and monoclonal antibody preparation and evaluation of the
safety and effectiveness of pharmaceutical products.
75. Inbred mice Immunology Oncology Microbiology Biochemistry
Pharmacology Physiology Anatomy Radiobiology offer a high degree of
genetic uniformity
76. Dog Kingdom: Animalia Phylum: Chordata Class: Mammalia
Order: Carnivora Family: Canidae Genus: Canis Species: C. lupus
Subspecies: C. l. familiaris and C. l. dingo
77. Beagle dog
78. Beagle dog
79. Beagle dog
80. Beagle dog with puppy
81. Mongrel dogs
82. Use of dog dog genome is similar in size to the genomes of
humans and other mammals, containing an estimated 2.8 billion DNA
base pairs. excellent model for researching numerous diseases
requiring subtle phenotyping many breeds of dogs are prone to
genetic diseases including cancer and autoimmune disorders that are
difficult to study in humans
83. Ferrets Kingdom: Animalia Phylum: Chordata Class: Mammalia
Order: Carnivora Family: Mustelidae Genus: Mustela Species: M.
putorius Subspecies: M. p. furo
84. Ferrets
85. Dentition 4 types of teeth (the number includes maxillary
(upper) and mandibular (lower) teeth) 12 small teeth incisors (only
a couple of mm) located between the canines in the front of the
mouth. used for grooming. 4 canines used for killing prey. 12
premolarlocated at the sides of the mouth, directly behind the
canines. The ferret uses these teeth to cut through flesh, using
them in a scissors action to cut the meat into digestible chunks
and to chew food 6 molars (two on top and four on the bottom) at
the far back of the mouth are used to crush food.
86. Dentition of ferret
87. Uses of ferrets Share many anatomical and physiological
features with humans virology, reproductive physiology, anatomy,
endocrinology, and neuroscience Experimental animal model for human
influenza Used to study the 2009 H1N1 (swine flu) virus Smith,
Andrews, Laidlaw (1933) inoculated ferrets intra-nasally with human
naso-pharyngeal washes, which produced a form of influenza that
spread to other cage mates. pathogenesis and treatment in a variety
of human disease e. g cardiovascular disease, nutrition Respiratory
diseases such as SARS and human influenza, airway physiology,
cystic fibrosis and gastrointestinal disease.
88. Study all aspects of canine distemper, a serious and fatal
disease of dogs and many forms of wildlife. Behavioral research:
suited to certain studies regarding learned behaviors.
Neuroendocrinology studies : domesticated species whose estrous
cycle in the female is easily monitored so an important animal
model for reproduction research Alternative to the use of dogs and
non- human primates in toxicology studies. Uses of ferrets
90. Mongolian gerbil known as the jird, clawed jird, sand rat,
or desert rat. Native to China and Mongolia Introduced into the US
in 1954. The most common color is the agouti, shown here: light
buff to white ventrum, with mixed white, yellow and black hairs
dorsally, giving an overall brown fur color.
91. Gerbils
92. Mongolian Gerbil
93. Gerbils
94. Pups of Gerbil
95. Behavior usually nonaggressive, curious and social. If a
gerbil escapes, it does not attempt to hide as other rodents do and
will often return to its cage. Nocturnal: most active in the
evening with cycles of activity during the day. Gerbils may form
stable, monogamous pairs and the male may assist the female in
rearing young. When they are excited or agitated they may audibly
stomp their large hindlimbs.
96. Uses of Mongolian gerbil Avg life : 3-4 years Good capacity
for temperature regulation High incidence of spontaneous neoplasms
with increasing frequency in aging animals ( 2 year). So unsuitable
for chronic toxicity studies. Malignancies involving the ovaries,
ventral sebaceous glands, kidney, adrenal glands and skin.
Abdominal sebaceous gland pad in the gerbil is androgen dependent
and readily observable
97. Uses Radiation studies: because they can tolerate much
greater whole-body radiation exposure than other animal species.
Endocrine gland metabolism studies: one of the largest ratios of
adrenal weight to body weight of all animals. Experimental
atherosclerosis Valuable animal model for stroke research. Most
animal species have a major arterial vascular supply to the base of
the brain - the Circle of Willis. This circle is incomplete in the
gerbil. Unilateral carotid ligation in the gerbil results in
ipsilateral cerebral ischemia. High incidence of spontaneous
epileptiform seizures, usually precipitated by a novel environment.
Parasitology research- successfully infected with parasites common
to other species
98. Uses of Gerbil Lipid metabolism: display lipemia and
hypercholesterolemia even on rodent diets with standard fat
composition. this results in hepatic lipidosis and gallstones, but
not in atherosclerosis. Reproduction studies to evaluate
antifertility drugs Auditory research: hearing curve is closer to
man's than most common laboratory animals. Psychology studies: due
to exploratory and territorial marking behaviors Toxicology
research: studies of food additives, pesticides, industrial
solvents and heavy metals. Infectious disease research:
99. Kingdom: Animalia Phylum: Chordata lass: Mammalia Order:
Lagomorpha Family: Leporidae Genus: Oryctolagus Lilljeborg, 1873
Species: O. cuniculus Rabbits
100. Rabbits small mammals 8 different genera in the family
classified as rabbits, including European rabbit (Oryctolagus
cuniculus), Cottontail rabbits (genus Sylvilagus; 13 species),
Amami rabbit (Pentalagus furnessi, an endangered species on Amami
shima, Japan). There are many other species of rabbit, and these,
along with pikas and hares, make up the order Lagomorpha. two
living families, the Leporidae (hares and rabbits), and the
Ochotonidae (pikas). The male -- buck The female doe young rabbit
is a kitten or kit
101. Rabbits Use is declined over the last decade because of
gradual and slight decline of the use of polyclonal antibodies
produced in rabbits Polyclonal antibodies still required bec they
are quicker and easier to produce than the monoclonal antibodies
Pyrogen testing of intravenous fluids and other technical products
intended for patients even though other test methods without live
animals are being evaluated Development of bio implant products
such as dental implants and devices for orthopaedic surgery Study
of atherosclerosis after being given high - fat and high -
cholesterol diets, which lead to the development of atherosclerotic
lesions in the major arteries after approximately 2 months.
102. Rabbits WHHL (Watanabe heritable hyperlipidaemic):
Spontaneously mutated strain develop atherosclerotic lesions in
their blood vessels even without the high - fat diet Toxicology:
detection of teratogenic effects of drugs because the embryological
development of the rabbit foetus is well known, the gestation
period is short and rabbits produce a fairly large number of
offspring Experimental teratology Cardiac surgery and disease,
joint surgery, ophthalmology and studies of hypertension
103. Opossum Kingdom: Animalia Phylum: Chordata Class: Mammalia
Order: Didelphimorphia Family: Didelphidae Subfamily: Didelphinae
Genus: Monodelphis Species: M. domestica
104. Order: Didelphimorphia small to medium-sized marsupials,
with the largest just exceeding the size of a large house cat, and
the smallest the size of a small mouse. semi-arboreal (often
inhabiting and frequenting trees but not completely arboreal =in
burrows) omnivores (eat everything), although there are many
exceptions. Most members of this taxon have long snouts (projecting
nose, jaws, or anterior facial part of an animal's head.), a narrow
braincase, Prominent sagittal crest (ridge of bone running
lengthwise along the midline of the top of the skull (at the
sagittal suture) of many mammalian and reptilian skulls). dental
formula is : 5.1.3.4: 4.1.3.4 By mammalian standards, this is a
very full jaw. The incisors are very small, the canines large, and
the molars are tricuspid.
105. Opossum Gray short-tailed opossum (Monodelphis domestica)
Small member of the Didelphidae family Possum = white dog The first
marsupial to have its genome sequenced. Marsupiam: fold of skin,
supported by epipubic bones, containing the mammary glands into
which young ones are placed. Habitat: Bolivia , Brazil and Paraguay
Frequently found in the exotic pet trade Biomedical research Also
known as the Brazilian opossum, rainforest opossum and in a
research setting the laboratory opossum.
106. Opossum
107. Opossum Readily available animals Suited for use in
studies of Melanoma Hypercholesterolemia Development of
arteriosclerosis, angiogenesis and corneal cancer because they are
altricial, Developmental studies are also done on their extremely
immature young. An increasing number of researchers are using the
laboratory opossum and considerable baseline data are now
available. M. domestica are easily cared for in standard rodent
cages and can be fed standard pelleted fox laboratory diet.
108. Primates Primates: Primates should only be used in
research programmes where there is particular need in justified
research programmes and where it can be demonstrated that the
benefits to society outweigh the harms inflicted on the animals
that are used.
109. Cat (Felis catus) Kingdom: Animalia Phylum: Chordata
Class: Mammalia Order: Carnivora Family: Felidae Genus: Felis
Species: F. catus
110. Primates The total number of primates used in research
worldwide is estimated at between 100 000 and 200 000, with 64.7%
involving Old World monkeys Most (up to 70 %) are used in
regulatory toxicology. The most common research areas for which
primates are used are: infectious diseases (including HIV/AIDS) 26%
neuroscience 19 % biochemistry 12 % pharmacology/physiology 11
%
111. New and old World monkeys New World monkeys E. g Squirrel
monkey, marmoset Native to Central and South America belong to
family : Callitrichidae, Cebidae, Aotidae, Pitheciidae, and
Atelidae Old World monkeys E. g Rhesus monkey Native to Africa and
Asia belong to family : Cercopithecidae
112. Rhesus monkey Rhesus Macaque (Macaca mulatta), also called
the Rhesus Monkey One of the best known species of Old World
monkeys. Kingdom: Animalia Phylum: Chordata Class: Mammalia Order:
Primates Family: Cercopithecidae Genus: Macaca Species: M.
mulatta
113. Rhesus monkey
114. Rhesus monkey
115. Squirrel monkey Squirrel monkeys and marmosets share many
physical characteristics, including small size and ease of handling
that contribute to their desirability as research subjects.
Squirrel monkeys ( Saimiri spp.) -- most commonly used neotropical
primates in US. Europe marmoset is used Adv: The mean body weight
of adult squirrel monkeys is less than 1 kg compared with female
rhesus monkeys, which usually weigh 4 5 kg. Smaller doses necessary
sp. Expensive medications easily adapt to laboratory housing
116. Squirrel monkey
117. Advs. of squirrel monkey smaller spaces and less expensive
cages req than larger primates, such as macaques and baboons. Less
risk of serious zoonotic disease transmission with squirrel monkeys
and other neotropical primates than with macaques and other Old
World primates. Accidental exposures from bites and scratches can
be managed in a manner similar to those from dogs and cats, and
personal protective equipment required for handling squirrel
monkeys is less extensive. Reduced risk to laboratory workers
combined with ease of handling, allow more procedures to be carried
out without chemical restraint or expensive handling equipment.
Easily habituated to handling, which further reduces stress from
manipulation. Experimental procedures that must be performed
without sedation can be carried out relatively easily in squirrel
monkeys.
118. Research models of squirrel monkey Physiological studies
of the effects of space flight -- ability to tolerate high
gravitational forces Atherosclerosis research- Wild squirrel
monkeys also have naturally occurring atherosclerotic lesions;
fatty streaks and plaques in aortas resembling human
atherosclerosis in lab. monkeys Experimental induction of
cholelithiasis Reproductive biology
119. Research models of squirrel monkey malaria vaccine
development studies- important animal model Plasmodium spp. are
host specific; therefore the animals used for studies of human
malaria must be susceptible to the same strains of Plasmodium that
cause disease in humans. The Bolivian squirrel monkey are superior
model than the Guyanese squirrel monkeys (S. sciureus sciureus) P.
Falciparum
120. One of the most susceptible non -human primate species to
experimental infection with Creutzfeldt - Jakob disease (CJD)
Transmissible spongiform encephalopathies Research models of
squirrel monkey
121. Transgenic animals Genetically engineered or modifi ed
mice are those with induced mutations, including mice with
transgenes, with targeted mutations (knockouts) and with
retroviral, proviral or chemically induced mutations . Transgenic
technology focuses on the introduction or exclusion (knockouts) of
functional genetic material in the germ line of an animal, thus
changing the genetic characteristics of an organism and its
progeny.
122. The most frequently used methods for genetic
transformation of the germ line are microinjection of DNA into the
pro nucleus of fertilized oocytes and the injection of transfected
embryonic stem (ES) cells into normal mouse blastocysts, resulting
in a subsequent generation of chimeras. These techniques have led
to the rapid development of a variety of animal models, designed
for the study of gene regulation, gene expression, pathogenesis and
the treatment of human and animal diseases (eg, Alzheimer s
disease, growth hormone disturbances, poliovirus vaccine testing ).
Transgenic animals