Mice in Research Flashcards
Taxonomy of mice
Order: Rodentia
Genus: Mus
Species: musculus
Outbred stock
Created by mating unrelated animals in a closed colony
Swiss webster, ICR and CD-1
Inbred mice
Minimum of 20 brother-sister matings
C57L/6, BALB/c, C3H, FVB, 129, DBA
What is significant about mice teeth?
Incisors grow throughout life (hypsodant)
Harderian gland
Produced secretion that lubricates the globe
How do mice respond to the cold?
Non-shivering
Neonates can’t control body temp until past 20 days of age
How do mice respond to heat?
Retreat to burrow to cool down
What is the lifespan of mice?
1-3 years and 4 years max
How are males distinguished from females?
By scrotal sac containing testis and by a longer anogenital distance
Breeding
- Monogamous
- Polygamous/harem= many females 1 male
- Rotating system= male moved between cages of females
Behavior
Nocturnal
Influences on behavior?
Time of day
Genotype
Environment
Pheromones
Environment
Temperature- 64-79F
Humidity- 30-70%
Ring tail
Tail is thermoregulator –> temps are above 80 and humidity under 40%
Nutrition
Fed ab libitum and hard pellets
Common research models
Genetic diseases (congenital muscular dystrophy)
Infectious diseases (listeriosis)
Viral infections (Hep C)
Aids
Xenografting
Signs of pain, distress or illness
Ruffled fur, hunched posture, red stains around the eyes
Mousepox
Viral disease transmitted by direct contact and skin abrasions
Clinical Signs and diagnosis of mousepox
Acute death, dermal rash and conjunctivitis
Serology
Pathology of mousepox
Intracytoplasmic eosinophilic dermal inclusions
Hepatoceullar necrosis (white foci throughout liver)
Treatment of mousepox
Depopulation and disinfection
Mycoplasmosis
Bacterial disease, gram-pos and common in pet and wild populations (resp. tract infection)
Transmitted by direct contact, aerosol and transplacental
Clinical signs of Mycoplasmosis
Suppurative rhinitis
Otitis media
Chronic pneumonia
Chattering
Dyspnea
Pathology of Mycoplasmosis
Squamous metaplasia, hyperplasia of submucosal glands, lymphoid infiltration of submucosa, suppurative bronchopneumonia
Diagnosis of Mycoplasmosis
ELISA, radioimmunosorbent assay, solid- phase radioimmunoassay
Culture (upper resp. tract)
Treatment of Mycoplasmosis
Tetracyclines (doesn’t eliminate infection)
Syphacia Obvelata
Common mouse pinworm diagnosed with anal tape impression and PCR
Lifecycle: 11-15 days
S. Obvelata eggs
Thin-shelled, crescent shape, flattened on one side
Deposited on perianal region
Infective in 6 hours
Airborne dissemination
S. Obvelata clinical signs
Usually asymptomatic
Heavy infestation:
Rectal prolapse
Intussusception
Enteritis
Fecal impaction
S. Obvelata treatment
Fenbendazole- medicated feed (9 weeks)
Ivermectin (6 weeks)
Piperazine (2 weeks)
Aspiculara tetraptera
Eggs are ellipsoidal and asymmetrical
Deposited @ night & excreted in mucous layer covering feces
Infective in 6-7 days
Diagnosis and treatment of A. tetraptera
Fecal float and cecal and colonic contents (necropsy)
Fendendazole and Ivermectin 1%
Hymenolepis nana (dwarf tapeworm)
Zoonotic
Asymptomatic but catarrhal enteritis, diarrhea, emaciation,chronic weight loss occurs with heavy infections
Diagnosis of Hymenolepis nana
Necropsy: worm in small intestine
Fecal float: hexacanth ova
Microscopy: segmented parasites or larve in small intestine
Treatment of Hymenolepis nana
Niclosamide: 2 treatments @ 7 day intervals
Myocoptes musculinus
Most common parasitic disease
Occurs in conjunction with Myobia musculi
Inguinal region, abdominal skin and dorsum, superficial dermis
Myobia musculi
Feed on skin secretions and interstitial fluid
Thermotactic
C57BL mice susceptible
Ulcerative Dermatitis
Most common in C57BL/6 and C57BL/10
Diet is a contributing factor
Clinical signs of ulcetative dermatitis
Alopecia, skin ulceration (scarring and disfigurement), pruritus
Older mice concerns
Chronic renal failure
Amyoid (alzheimers)
Lymphocytic coloal meningitis (zoonotic)
Mammary tumors
Viral: mouse mammary tumor viruses (MMTV)- C3H, BALB/c and GR strains
Found all over the body
