11. The Guinea Pig and Hamster in Research Flashcards
Guinea pigs are in what suborder?
Histricomorphs (Porcupine like) - masseter passes through large infraorbital foramen
Guinea pigs are old or new world rodents?
New world
Guinea pigs were the first to b emaintained in axenic state. what does this mean?
Free of other microorganisms
Describe length and texture of coats in English, Peruvian, Abyssinian GPs
English: Short and straight
Peruvian: Long (whorled or straight)
Abyssinian: Short, rough hair in whorls
Outbred stock of GP
Dunkin-Hartley
Inbred strain of GP
Strain 2, Strain 13, JY1, JY2, Weiser-Maple
JY1 and JY2 GPs
Used for superovulation, embryo transfer, embryo culture
Weiser-Maple strain
Radical and vertical growth patterns of melanocytes
Strain 2 and Strain 13
multicolored, lower growth rates, less robust
Hartley A
Natural resistance to T. pallidum
Complement 4 deficient
100% susceptible to T. pallidum - partial autosomal dominant
Waltzing GPs
Deafness and circling behavior - Autosomal dominant
German waltzing
Inner ear deficiency - deafness, ataxia, circling - recessive
Homozygotes affected, hets have increased resistance to noise induced trauma
Hairless athymic
immunodeficient (agammaglobulinemia)
Hairless euthymic
Immunocompetent
Life span of GPs
2-8yrs
Sexual maturity of GPs
60-90days
Estrus cycle length GP
16-18 days
Gestation length GP
60-65 days
Avg litter size GP
2-4
GPs are unable to synthesize Vit C due to lack of what?
L-gulonolactone oxidase
Palatal ostium in GPs
Soft palate is contiuous with tongue, causing small hole - palatal ostium
Unique cytology
Predominant WBCs
Heterophils
Kurloff cells
What are Kurloff cells?
Estradiol-dependent mononuclear leukocyte
Help prevent maternal rejection during pregnancy - form barrier in placenta
What is unique about GP distal bronchi?
Most prominent smooth muscle compared to other mammals
Which cells are abundant in GP lungs?
Mast cells, eos
What’s unique about GP pulmonary arteries?
Marked thickening of media
Surrounded by prominent concentric bands of smooth muscle
Excess dietary cholesterol leads to what in GPs?
Acute hemolytic anemia
What’s unique about GP renal arteries?
2-3 pairs supply each kidney
GP uterus
Bicornuate, single cervix
Why should females be bred <6mos of age?
To prevent dystocia from pelvic symphysis
Preyer response
Pinna tilts rearwards with sharp sounds
Used in otologic research
Why are GPs used in research?
Long gestation period with mature neuro systm at birth
Large TB
Nutritional characteristics
Buehler test
Compound applied to skin topically 3x followed by challenge
GPs are used to study which herpesvirus?
HSV2 (simplex)
Sereny test
Assay for bacterial invasiveness - organisms placed in conjunctival sac, leading to development of keratoconjunctivitis
Suborder of hamsters
Myomorpha
Syrian/golden hamster g/s
Mesocricetus auratus
Chinese/grey hamster g/s
Cricetulus griseus
European/black-belled hamster g/s
Cricetus cricetus
Armenia/migratory hamster g/s
Cricetulus migratorius
Djungarian, Siberian, Dwarf, striped hairy footed hamster g/s
Phodopus sungorus
Lifespan of hamsters
1.2-2 years
Avg litter size of hamsters
5-10
Gestation period for hamsteres
15-16 days
How are hamster cheek pouches unique?
Lack lymphatic drainage pathways - immunologically privileged
Flank glands of hamsters develop neoplasia when what happens?
With simultaneous stimulation by androgens and estrogens
Which strain of hamster is used for cardiomyopathy?
Strain BIO 14.6
Hamsters were the first animal model for Cushing’s or Addison’s?
Addison’s
Application of what to hamster cheek pouches causes SCC?
DMBA
Hamster cheek pouches are ideal for what kind of graft?
Xenograft without rejection
