What are mice mainly used for?
most common animal used for research
Are mice popular pets?
What are mice raised for?
to feed predators
What is the life span of a mouse?
about 3 years
Do mice get sick easy?
no, they are hardy animals
How much do mice weigh?
about 30 grams
What are nude mice missing?
What are nude mice used for?
Do nude mice have the same life span as other mice?
no, they have a shortened lifespan
What tools can you use to restrain mice?
- mesh gloves
- light weight leather gloves
- sponge forceps to grab scruff or base of tail
- clear plastic jar
Are mice continuously polyestrous?
What is the gestation length of mice?
about 21 days
When are mice weaned?
at 3 weeks
How old are mice when we first breed them?
about 50 days old
When do we stop breeding mice?
around 8 months old
Do mice have postpartum estrus?
What is monogamous?
one pair breeding together
What is polygamous?
- 1 male stays with 2 - 3 females
- male moves from female to female
What is the Bruce effect?
recently bred mice abort if exposed to strangle male
What is Whitten effect?
- anestrus in females housed together with no male
- estrus synchronization
How do we collect blood from the orbital sinus?
- anesthetize patient
- use a heparinized capillary tube
- push tube through the conjunctiva and when it hits the sinus it will start to bleed and fill up the tube
Other than the orbital sinus, where else can we collect blood from a mouse?
- cephalic and lateral tail vein
- patient can be awake
What can we put on a vein to make it stand up better to see?
an irritating astringent or hot water
How do we collect blood using the cardiac puncture?
- anesthetize patient
- stick patient right beside the xyphoid
What are the different types of injections we can do for mice?
- intraperitoneal (into abdominal cavity)
- intramuscular (avoid if possible)
Why do we avoid doing intramuscular injections in mice?
easy to damage nerves and muscle
How do we use a gavage on a mouse?
- measure dosing needle from tip of nose to last rib
- restrain mouse
- follow curve of GI tract - don't force it
Why do we need to be concerned about the food intake of mice?
mice have a high metabolic rate and can starve to death easily
When do we usually see pneumonia in mice?
stress in large numbers
What are the clinical signs of pneumonia in mice?
- teeth chattering
- dyspnea (difficulty breathing)
- weight loss
Does bacteria or viruses cause pneumonia in mice?
both can cause pneumonia
What are some of the etiology for pneumonia in mice?
- cilia associated with respiratory bacillus
- sendai virus (most common)
What does Helicobacter sp. cause in humans?
What causes Helicobacter sp. in mice?
- inflammatory bowel disease
How do we treat Helicobacter sp.?
antibiotics (injection or gavage)
What causes Tyzzer's disease?
Can we culture clostridium piliforme easily?
no, it is anaerobic
Which mice do we usually see Tyzzer's disease in?
young and stressed (usually due to transport)
What are the clinical signs of Tyzzer's disease?
- sudden death
- milliary pale foci in liver (lesions on liver seen on a necropsy)
What causes staph/strep infection in mice?
- bite wounds
- cervical lymphadenitis
What is cervical lymphadenitis?
swelling under the jaw
What type of virus is the mouse hepatitis virus?
a corona virus
What does the mouse hepatitis virus affect?
Is mouse hepatitis virus contagious?
yes, it is highly contagious
What environments do we usually see the mouse hepatitis virus in?
Mouse hepatitis virus is a subclinical virus. What does this mean?
we don't see any clinical signs and in pet mice we don't even know they have it but it can affect the results of some research
What does LIVIM stand for and what is it related to?
- lethal intestinal virus in infant mice
- mouse hepatitis virus that is transfered to baby from the mother and kills it at birth
If mouse hepatitis virus is in a breeding program, what do we do?
stop breeding for 8 - 15 weeks and then start breeding again
What is Epizootic Diarrhea of Infant Mice? When do we see this infection start? What are the clinical signs of this infection?
- rotoviral infection
- 1 - 3 weeks of age
- stunted growth and soft yellow feces
What is lymphocytic choriomeningitis?
- zoonotic flu like viral disease
- transmitted from handling rodent
What are some other diseases mice can get?
- ectromelia (pox virus, uncommon)
- parvovirus (uncommon)
- encephalomyocarditis virus (elephants get this from mice)
- hantavirus (seen in wild mice and is zoonotic, spread in feces of mice)
What are the parasites that mice can get?
- pinworms - Syphacia (hair loss around base of the tail, very common and irritating)
- tapeworms - Hymenolepsis
When do we typically find pinworms (Syphacia) in mice?
- usually seen when doing a fecal on an animal that has eaten the mouse
- banana shaped worm that we don't treat
What is the most common parasite in mice?
How do we diagnose and treat mites in mice?
- do a skin scraping
- treat with ivermectin
What is barbering in mice?
animal chewing on another animal
What are the signs of barbering?
- rough hair coat
- skin lesions in extreme cases
How do we treat barbering?
remove the animal that is doing the chewing...it is usually the animal without the rough hair coat or lesions
What is the most common subcutaneous tumor in mice?
Are most mammary tumors malignant?
Which mice do we typically see mammary tumors in?
older mice...>1 1/2 years old
What is the problem with malocclusion in mice?
can interfere with the mouse eating