lab animals

1. GUINEA PIG, HAMSTER, RABBIT
By
Dr.Elza Joy
Munjely

2. GUINEA PIG

3. • Cavia porcellus
• Suborder “Hystricomorpha”
• Herbivorous-green foods,seeds &
roots,readymade chow diet

4. • Very docile
• Require vit C in diet
• If greens -1 g/L of drinking water
per week
• If chow -200mg/L per day

5. BIOLOGICAL DATA
PARAMETER DATA
Mass 0.7 to 1.2 kg
Length 20 to 25 cm
Lifespan 4 to 8 years
Gestational
period
59 to 72 days

6. • Best mated after 3 months of age
• Sensitive to various diseases &
infections  so suitable for
diagnostic tests

7. GUINEA PIG AS EXPERIMENTAL ANIMAL
Ideal model for
• Enteric amoebiasis
• Hypersensitivity
• Immune response
• Anaphylactic shock
• Encephalomyelitis
• Tuberculosis
• Bronchial asthma
• COPD
• Ascorbic acid metabolism
• Screening of local anaesthetics
• Bioassay of digitalis

8. • Highly sensitive to HISTAMINE &
PENICILLIN
• Serum contain Asparaginase
Antileukaemic action

9. HANDLING TECHNIQUE
Can be easily handled
• Way 1By using both hands,
calmly grasp it with one
hand under the chest &
use your other hand
to support its hindquarters

10. • Way 2Handle guinea pig with one hand , by
holding its hind quarter

11. SEX DETERMINATION
• Female-detectable pink nipple on
either side
• Male-Penis & testes are palpable in
adults

12. Bleeding & I.V injection
• Small quantities from marginal ear vein
• Heart puncture after anaesthesia or
Carotid A after stunning/inducing anaesthesia
• Males penile Vs

13. INTRAGASTRIC ADMINISTRATION
• Similar to rat
• 15 to 16 gauge hypodermic needle of 7.5 to
10 cm length is blunted

14. HAMSTER

15. • Mesocricetus auratus
• Different strains
–Syrian hamsters-most commonly used,rapid
development & short life cycle
–Chinese hamster-lowest number of
chromosomes(22)used for cytogenesis research
–European hamstersuitable for smoke
inhalational studies
–Armenian hamsterspecific for carcinogenic
& mutagenic agents

16. BIOLOGICAL DATA
Parameter Data
Mass 20-40g
Lifespan 3 years
Gestational
period
22 days

17. • Cheek pouchcollection & transport of food
materials,lack intact lymphatics.
• Whiskersfound on face & side of the body
to navigate the surroundings & object around
them esp. at night,= “vibrissae”
• Small tail & very loosely packed skin

18. Hamsters as experimental animals
Spontaneous model of human diseases such as
• Diabetes mellitus due to deficiency of β
cells/presence of defective β cells in the
pancreas
• Syrian hamster dystrophy
• Cholesterol cholelithiasis
• Polycystic diseases
• Dental caries

19. • Slow virus type C,Oncovirus,influenza virus,respiratory
syncytial virus studies & vaccine production
• Cheek pouches lack lymphatic drainage, so ideal site for
tissue transplants,such as tumours & grafts,pouch can be
pulled out under anaesthesia & can be stretched over an
illuminated surface for observation
• Strips cut from cheek pouchassay for prostaglandins E & F
• Invivo & invitro diagnostic techniques for infectious agents
i.e Clostridium spp,Leptospirosis spp

20. HANDLING TECHNIQUES
• Way 1Hold the complete body by grabbing
at the nap of neck by thumb & index finger&
grasp the complete body by using rest of
fingers

21. • Way 2Hold the complete
body by grabbing back
by using complete palm

22. RABBIT AS AN EXPERIMENTAL ANIMAL &
INJECTION TECHNIQUES IN IT

23. Rabbit (oryctolagus cuniculus)
• Rabbits are very docile animals (2n =44 )
• FamilyLeporidae OrderLagomorpha
• Domestic - Oryctolagus cuniculus
• Wild - Sylvilagus,
Coprolagus,
Nesolagus,
Brachylagus

24. Common Strains
• Newzealand white rabbits most
commonly used
• Dutch
• Flemish Giant
• 1916 - WS Preshaw bred first litter of
Newzealand white rabbits

25. StrainsNewzealand white
Dutch
Flemish Giant
Wild

26. ANATOMICAL PECULIARITIES
• Simple cardiac conductive tissueAnimal of
choice for many cardiac studies
• No adrenergic vasodilator nerves No
Vasomotor reversal phenomenon
• Dopamine - fall in BP
• Histamine - rise in BP
• Very sensitive to histamine

27. ANATOMICAL PECULIARITIES
• Cannot vomit
• Genetic relationship b/w atropine esterase &
black pigmentation of the fur
• Wide field of vision
• Long ears-heat regulation
• Cytochrome 3A4 is absent

28. Reproductive cycle
• Non spontaneous ovulation
• Coitus induced Ovulation
• LH release 10 hrs after coitus
• Progesterone inhibits ovulation
• No seasonal anoestrum
• Short gestation period --31 days
• Duration sexual life - 36 months
• No of litters per year - 4

29. Biological Data
PARAMETER DATA
Adult weight 1.5-5 kg
Average life span 4-6 years
Age suitable for experiment 6 months
Age of first mating 6-7 months
Breeding habits (no of females to 1
male)
1
Gestation period 31 days
No of litters per year 4

30. Guidelines for animal handling
• Pet or soothe the animal by slow deliberate
movement on their body.
• Overcrowding near animal cage to be avoided.
• Noise - minimum as possible.
• Do not hold the animal too hard
• Agitation - lead to violent behavior for self
protection

31. Handling techniques----
By using single hand ,hold
the pelvic region
By using both hands ,calmly grasp
it with one hand supporting back of
neck & the other hand supporting
its hindquarters

32. Handling techniques---
By using both the hands, hold the
complete hindquarter

33. Sex differentiation
FEMALEFEMALE MALEMALE

34. Rabbit as an experimental animal
• Pyrogen testing in IV fluids
• To test toxic effects of cosmetics &
pharmaceuticals
• Good model for production of antibodies &
antiserums
• Study of agents affecting capillary
permeability

35. Contd-
• Screening of drugs for
TB, diabetes, diphtheria, cancer, heart
disease,embryotoxic drugs
• Study of topical irritants
• Insulin & other antidiabetic drugs
• Curare & sex hormones
• Studying circadian rhythmicity -

36. Contd -
• Suitable for research in reproductory
studies
- no seasonal anoestrum
- ovulation non spontaneous
- short gestation period
- semen easily collected

37. Contd -
• Widely used in eye experiments
 Underdeveloped tear mechanisms
 Very clear eyes , effects easily visualised
• Biomedical research studies
Immunology, Genetics, Nutrition, Toxicology,
Physiology

38. Isolated tissues
Tissue Assay Effect
Heart Adr,NA,Hist,Ach Contraction
Duodenum Adr,NA Relaxation
Ileum Barium,Ach Spasms
Jejunum ,, ,,
Ear artery NA,Hist,5HT Constriction

39. Zoonotic diseases spread while
handling rabbits
• Ring worm infection
• Mites
• Allergens
Glycoprotein in fur
proteins found in urine and saliva

40. Diet
• An average 1kg rabbit can be given 40g
concentrated feed and 40g green fodder.
• Concentrated feed available as pellets

41. INJECTION TECHNIQUES

42. Precautions before injection
1. Injection site to be cleaned with a suitable
disinfectant/antiseptic(75%
alcohol/betadine)
2. Sterile syringes and needles to be used.
3. Always select smallest possible gauge to
limit tissue trauma.
4. Aspiration technique is an important aspect
before pushing injection solution at the site.
5. Ensure no air bubble in syringe

43. Intravenous injection
• Marginal ear vein preferred
• Restrain the rabbit
• Lateral margin of ear is shaved
& swabbed with disinfectant
• 22-24G needle used

45. Insert needle into the ear vein with
the bevel up

47. • Maximum volume that can be injected iv in
rabbit is 10ml

48. Subcutaneous injection
• Easy due to laxity of skin
• Not to be done on neck
• 22 G needle used
• Not more than 5 ml/site

49. Intra muscular injection
• Mainly for antibiotics
• Less than 1.5 ml injected
• Lateral thigh and buttocks preferred
• 21 -22G needle used

50. Methods of blood collection
Sites
Marginal ear vein
Central ear artery
Cardiac puncture

51. Marginal ear vein-
Bruising and hemorrhage can occur
22-24 G needle used

53. Central ear artery
• Large quantity can be collected(5-50 ml)
• 24-26 Gauge needle used

54. Cardiac puncture
• Terminal method
• 19-2l G needle used
• Base of sternum under xiphoid at 30-45
degree angle lateral to midline

55. Intragastric administration
Wooden gag with a small hole
is placed in the mouth
No.12 french catheter
or
No 9 soft rubber catheter
used