Common complications: Dystocia, hypocalcemia, uterine prolapse
Guinea pig Nutritional Requirements
Type of eater:
Special nutritional requirements:
Type of eater: Herbivores and cecal fermenters - Coprophagy for Vit B and K - Grass is primary constituent of natural diet
Food intake: 6 grams feed/100 g body weight/day
Water intake: 10 mL/100g body weight/day
Special nutritional requirements: Only laboratory animal (other than primates) that require Vitamin C (ascorbic acid) because they are unable to synthesize it
List 5 Complications associated with Guinea pigs becoming Vitamin C deficient
Delayed wound healing
Impaired tooth and bone formation
List 6 Guinea pig behaviors
1. Very social- always house together if possible
2. Thigmotactic (feels way around cage)
3. Not aggressive with people
4. Will bite one another, chew off ear tags
5. "stampeding" behavior - Haphazard running to confuse predators/aggressors
6. Messy eaters - tend to stuff bedding into sipper tubes
What are 4 Rodent husbandry considerations?
Describe the housing
Shoebox caging using Mouse micro isolator cages with filter in tops that excludes pathogens, traps moisture and gases. The caging is made up of polycarbonate material (strongest, most expensive)
The shoebox caging is stored on Rack systems that are Flat shelves and ventilated. Ventilated systems help to keep the cages dry and allows for longer intervals between change outs. Ventilated systems can be used with water bottles or auto water systems
Water and water delivery
What type of water is used?
What are 4 types of water treatments that are used?
3 Methods for Water delivery
Describe the process of using Inhalation anesthesia.
Place the animal in a closed container containing cotton or gauze soaked with agent; vapors are inhaled, animal becomes deeply anesthetized, respiration ceases and animal expires. Do not allow animal to come into contact with agent or allow air to circulate in the container. Not commonly used as a stand alone method. May be used to anesthetize an animal before a secondary method is used.
What are 3 Advantages and 3 Disadvantages to using Inhalation Agents?
Advantages 1) Good for small animals or for animals that are hard to restrain; 2) Many clinics have anesthesia machines; 3) Most agents are nonflammable and non-explosive
Disadvantages 1) Some struggling and anxiety may occur; 2) Cannot be used without good ventilation or an anesthetic machine; 3) May require a secondary method
Inhalant anesthetic is recommended for what animals?
Small animals that are hard to restrain and birds - most likely will just anesthetize the animal and then inject with a barbiturate or exsanguinate
Describe the process of using Carbon dioxide for eusthansia
Place animal in chamber filled with CO2. Animal loses consciousness due to anesthetizing effect of CO2, then asphyxiates. This method is commonly used for rodents in research. A secondary method must be used, such as tissue removal or exsanguination
What are 3 Advantages and 1 Disadvantage to using Carbon dioxide
Disadvantages - Cannot be used on neonatal animals
Carbon dioxide is recommended for what animals?
Good for small laboratory animals, except neonates or very young animals
What are 2 types of Injectible agents used for euthanasia?
List 2 agents used with barbiturate euthanasia and describe the method/process.
Method-intravenous in most animals, or other routes if animal is already unconscious. Pentobarbital overdose can be given IP to rodents. Thiopental must be given IV.
What are 2 Advantages and 4 Disadvantages to using Barbiturates?
Advantages - Fast and Minimal discomfort to the animal in most cases
Disadvantages - 1) Necessitates trained personnel to restrain animal and give injection; 2) Regulated-must have DEA number; 3) Terminal gasp is aesthetically objectionable; 4) Excitability is occasionally possible as animal passes through stages of anesthesia
Barbiturates are recommended for what animals?
Preferred method for dogs, cats and many other small animals, can be used in large animals
IP injection of pentobarbital is acceptable in rodents
Apprehensive animals may require pre-tranquilization with Valium, acepromazine or other sedatives
List the agent used with Potassium chloride euthanasia and describe the method/process.
Agent-Supersaturated solution of potassium chloride (KCI)
Method-Given IV only in DEEPLY anesthetized animals. Too much KCI added to IV fluids could also harm the animal-be careful if you're adding this to IV fluids!
What are 3 Advantages and 2 Disadvantages to using Potassium Chloride?
Advantages - Inexpensive; Fast; and Non-regulated
Disadvantages - Animal must be anesthetized; and Painful if animal is not deeply anesthetized
Which method is used mainly in research. Could be an alternative to other injectable
drugs if animal is already anesthetized.
List the agent/device used with physical method of euthanasia and describe the method and action of the process.
Captive bolt pistol
Method - Animal is restrained. Pistol is placed between the eyes and perpendicular to the skull and then discharged.
Action - The bolt penetrates the skull and significantly damages the brain to cause unconsciousness.
What is an Advantage and 2 Disadvantages to using Captive bolt pistol?
Advantages - Humane method for large animals that cannot be euthanized with drugs if used correctly
Disadvantages - Aesthetically displeasing and Death may not occur
Captive bolt pistol is recommended for what animals?
Acceptable for large animals when chemical agents cannot be used, as long as it is followed by exsanguination or transection of spinal cord at base of brain to ensure death.
List 3 secondary methods to ensure death in euthanasia.
Describe the Cervical dislocation Method of euthanisia
Method - Place thumb and index finger on either side of the neck at the base of the skull. With the other hand, the base of the tail is quickly pulled to separate the neck vertebrae.
Cervical dislocation is recommended for what animals?
Must be done in anesthetized animals.
Considered appropriate for small birds, mice and rats under 200 grams; and rabbits under 1 kg
Describe the Exsanguination Method of euthanisia
Method - Remove 75% of the blood volume after the animal has been anesthetized
Exsanguination is recommended for what animals?
Can be used in all anesthetized animals to ensure death. In research, is used when large volumes of blood are needed or when tissues must be used for histopathology or other tests.
Describe the Method -
It is recommended for use in what animals?
Method - liquid nitrogen is used to freeze brain tissues
Used in research when brain biochemistry is important for the study
What precautions should you take if you have allergies to rodents?
Wear PPE (personal protective equipment) consisting of mask, gloves and gown
Discard PPE when finished and wash hands well
Leave room if necessary
____________ was the first mammal to be used in research
Rattus norvegicus, the Norway rat,
______________________ is the most frequently used animal in biomedical research
Mus musculus, the house mouse of N. America and Europe
When and for what animal(s) can you use the tail hold?
Describe this method of handling
What can happen with incorrect handling?
Short term handling only for the mouse and rat
grasp tail at the base (fat part) not the tip
Grasping tail tip may cause the skin to "slough" off
Describe the Scruff hold and indicate what animal this technique is used for.
Used for: mouse - Provides greater restraint
Start with tail hold, place mouse on surface it can grip. Continue to hold tail, then grasp the loose skin at the back of the neck (the "scruff'). Grasp the skin close to the head to prevent bites. Hold tail between 4th and 5th fingers to steady mouse
Describe the Body hold and indicate what animal this technique is used for.
Used for: rat - Provides better restraint of rat
Place hand over rat's body. Restrain head with first and second fingers. Place thumb and third finger behind front legs. For aggressive rats, wear leather or mail gloves
What type of restraint device could you use that allows access to tail, other areas for injections, drawing blood?
Plexiglas restrainer - tail, other areas for injections, drawing blood
What is the name of the Plastic "baggie" used to place rodent inside that leaves the tail free for injections or you can inject IP/IM through baggie
What restraint device is useful when taking blood sample from saphenous vein in mice?
What precaution do you need to take when using this device?
Cut hole in end for air
What are 3 pros and 4 Cons to anesthetize a rodent for procedures
Pros: 1. No movement; 2. Good access anywhere on body; 3. Short or long periods
Cons: 1. Must monitor anesthetic depth; 2. Vaporizers are expensive; 3. Chemical anesthetics - need DEA number; 4. Anesthetics may cause vasoconstriction
List 2 animals identification methods
What information must be on cage ID card?
Should list investigator's name, species, strain, vendor, age, sex, arrival date
What are 6 types of individual IDs that may be used in research?
Toe amputation (hairless neonates only)
Shave patterns into fur
Indicate the size of the Oral gavage Needle:
Mice: 20 gauge, 1 ½ inch
Rats: 18 gauge, 3 inch
Describe the procedure for oral gavage
Restrain animal and measure distance from mouth to last rib with feeding needle. Note how far you have to pass needle to be in stomach Place gavage needle in mouth and pass it down esophagus by sliding it along roof of mouth. Animal should swallow as needle passes. At correct depth, give fluid. Monitor for signs of discomfort, difficulty breathing, abnormal behavior
What are 2 methods for giving oral medications?
Some antibiotics or pain medications can be placed in the animal's water bottle
A sweet flavored antibiotic can be given by dropper into the back of the mouth
Grasp tail, rotate slightly to see veins and choose injection site a little over half way down the tail
Insert needle through skin with the bevel up
Usually cannot check for placement by aspirating
Inject fluid and check for clearing of vein
If SQ lump forms, you are not in vein - Withdraw needle, try again closer to body
How much fluid can be given via Tail Vein injection to a mouse and a rat?
up to 0.2 mls (mice); 0.5 mls (rats)
Which type of injection is not recommended in a mouse?
Intramuscular Injections -
Needle size for rats:
How do you restrain?
Where do you inject fluid?
How much fluid can you give?
Needle: rat: 25 gauge, ½ inch
Restrain rat: hand-held, restrainer, anesthesia
Inject fluid into posterior (caudal) thigh muscles
Can give up to 0.3 mls (rats)
Blood Collection - Blood volume
Mouse: 70-80 ml/kg or approx. 5.5% of body weight
Rat: 50-65 ml/kg or 6-7% of body weight
5 locations for blood collection
Lateral tail vein
Ventral tail artery
Retro-orbital venous sinus
Describe the procedure for collecting blood from the Lateral Tail Vein for a mouse.
Vasodilate tail vessels
Restrain mouse so that vein is visible
Use a scalpel blade to nick the skin and pierce the vein
Collect blood as droplet wells up in Microtainer or capillary tube
When finished, hold pressure on site or cauterize
Can obtain up to 0.2 mls of blood
Describe the procedure for collecting blood from the Lateral Tail Vein for a rat.
Vasodilate tail vessels
Restrain rat so that vein is visible
Use a 25 gauge needle on a 1 cc syringe to withdraw blood
Alternatively, place a 25 gauge needle in vein without syringe and collect blood in capillary tube
Describe the procedure for collecting blood from the Ventral Tail Artery for a mouse or rat.
Vasodilate tail vessels
Restrain animal and lift tail - Artery runs on the ventral side
Use a scalpel blade to nick the skin and pierce the vessel and collect blood as the droplet wells up in a Microtainer or capillary tube
Can also use a 25 gauge and 1 cc syringe to withdraw blood in rats
How much blood can you obtain from the Ventral Tail Artery from a mouse and rat?
up to 0.4 mls (mice); 1.0 ml (rats)
Describe the procedure for collecting blood from the Saphenous Artery for a mouse
Vasodilate the animal with a heating lamp/pad
Restrain mouse in centrifuge tube
Can use Isoflurane anesthesia for rat
Use clippers to shave fur over site on rear leg
Place small amount petroleum jelly on site
Use a 20-22 gauge needle to pierce the skin and nick the vessel
Collect the blood as a droplet wells using a Microtainer or capillary tube
When finished, hold pressure on the site or cauterize
Monitor for further bleeding from site
Describe the procedure for collecting blood from the Retro-orbital Venus Sinus
The animal MUST be anesthetized
Use a capillary tube or Pasteur pipette to place pressure on the conjunctiva at the medial canthus (inner comer) of the eye
Twist slightly until the tube pops into the venous sinus
Place a gauze pad over eye, closing eyelids and use gentle pressure to prevent hematomas
How much blood can you obtain from the Retro-orbital Venus Sinus from a mouse and rat?
0.2 mls (mice)
0.5 mls (rats)
Describe the procedure for collecting blood via a Cardiac Punture
Animal MUST be anesthetized
After anesthetized place animal on its back
Insert the needle (22 gauge, 1 inch) under the xiphoid cartilage at a 30o angle
Aspirate slowly as needle is advanced slightly until blood enters syringe
Can also approach from behind left foreleg with animal lying on its right side
What animals would you use the cardiac Puncture method of blood collection?
Recommend that this be used as a terminal procedure only
How much blood can you obtain from the Cardiac Puncture from a mouse and rat?
up to 1.0 ml (mice); 6 mls or more(rats)
What are the steps for an experimental study?
1. Identify the problem
2. Review peer literature, interview experts in field and obtain other information on your subject through literary search.
3. Determine the system or model to be used in experimental study.
4. Create a clear and concise hypothesis
5. Test theory using step by step schedules, baselines, control groups and experimental treatment groups
6. Record the findings
7. Analyze and document the results
8. Report findings
What is a hypothesis?
An educated theory on the outcome of the experiment.
What are some concerns that should be addressed in your experimental proposal?
Safety concerns and how to minimize them
Describe any animal manipulations and methods for minimizing adverse effects on animals
Make sure all personnel are properly trained on seaftey precautions, handling and accessing the animals welfare (eating, drinking, activity)
Who must you submit a proposal for research experiment to?
To funding agency
To safety committee
To institutional animal care and use committee
Animal Research is Governed by
State and local governments
Institutional regulations and policies
Define the following terms and give an example of each
Epizootic: Acute outbreak; usually associated with clinical signs. Example - Mouse Pox virus
Enzootic: Disease exists within the colony but usually at a subclinical level. Example - Mouse Parvo virus
Fomite: an inanimate object that transmits a disease agent. Examples - bedding, gloves, instruments
Vector: a living thing that transmits a disease agent. Example - mosquitoes and Heartworm disease
Define burn out
to stop breeding and introductions of new animals while allowing a colony to be infected by, and recover from, a disease agent. Results in immunity of resident animals and stops transmission to new inhabitants. Example - Mouse Hepatitis Virus
List 5 Viral diseases of mice
Mouse hepatitis virus
Mouse Parvovirus/Minute virus of mice
Epizootic diarrhea of infant mice
Immunodeficient mice with clinical signs of hunched posture, failure to thrive and progressive wasting (nude mice) are signs of what disease of mice?
Mouse Hepatitis Virus (MHV)(Corona Virus)
What are 6 ways the Mouse Hepatitis Virus (MHV)(Corona virus) is transmitted?
Fecal-oral, aerosol, direct contact, vertical, fomites, and Biologic products
What is the treatment for Mouse Hepatitis Virus (MHV) (Corona Virus)?
None. Virus eventually clears itself. May consider burn-out
What are the 3 ways the Mouse parvovirus/minute virus of mice is transmitted?
Fomites: resistant to disinfection
Direct contact with feces or urine
What is the treatment of Mouse parvovirus/minute virus of mice?
None. Some strains clear the virus; in others can persist for months
Once established in a colony, cannot be eliminated (no burn-out)
What disease is characterized by clinical signs of diarrhea, wasting and death in unweaned mice?
Epizootic Diarrhea of Infant Mice - EDIM (Rotavirus)
What are 2 methods of transmission for Epizootic Diarrhea of Infant Mice - EDIM?
What is the effect of Epizootic Diarrhea of Infant Mice on research?
Stunted growth; animal losses
What is the treatment of Epizootic Diarrhea of Infant Mice?
older mice resistant and can be carriers.
Supportive care of affected infants
What disease is characterized by clinical signs of severe pneumonia in DBA mice?
What are the methods of transmission for Sendai Virus in mice?
What is the effect of Sendai Virus on research mice?
Effects on immune system; death of susceptible mice
What disease in mice is characterized by clinical signs of typical pox lesions, loss of extremities, death that can destroy a colony of mice?
Ectromelia (Pox virus)
Which mice are resistent and which are susceptible to Ectromelia (Pox virus)?
C57BL/6 more resrstant
C3H and BALB/c susceptible
What are the methods of transmission for Ectromelia (Pox virus) in mice?
Biological products- most common vector today
Direct contact, fomites
What prevents the transmission of Ectromelia in mice?