Rats Flashcards
Scientific name of the norway rat
Rattus norvegicus
scientific name of the black rat
Rattus rattus
Primary research use for: ACI rat
genitorurinary congenital issues
prostate adenocarcinoma
Primary research use for: biobreeding (BB/Wor) rat
diabetes mellitus type 1
Primary research use for: brown norway (BN) rat
myeloid leukemia
hydronephrosis
bladder carcinoma
Primary research use for: buffalo (BUF) rat
thyroiditis
hepatoma
Primary research use for: Copenhagen (COP) rat
prostate adenocarcinoma
Primary research use for: F344 rat
toxicology
leukemia
Primary research use for: Lewis rat
MS
autoimmune dz
Primary research use for: LOU/C rat
myeloma antibody production (IgG)
Primary research use for: SHR rat
hypertension
Primary research use for: WF (Wistar-Furth) rat
leukemia
Primary research use for: Zucker rat
obesity
Primary research use for: brattleboro rat
diabetes insipidus
Primary research use for: Gunn rat
jaundice, kernicterus
Primary research use for: nude rat
T cell deficiency
Primary research use for: Obese SHR rat
type 4 hyperlipoproteinemia (obesity + hypertension)
Space required by the guide for a rat <100g?
17in2
Space required by the guide for a rat <200g?
23in2
Space required by the guide for a rat <300g?
29in2
Space required by the guide for a rat <400g
40in2
Space required by the guide for a rat <500g
60in2
Space required by the guide for a rat >500g
> 70in2
Space required by the guide for a rat with her litter?
124in2
Cage height required by the guide for rats?
7in
Stress and illness result in what symptom characterized by red pigment around the eyes?
chromodacryorrhea
How can porphyrin pigment be differentiated from blood?
Porphyrin fluoresces
Hearing range of rats?
250Hz- 80kHz
What limiting ridge separates the glandular and nonglandular portions of the stomach?
Margo plicatus
T/F: Rats have a gallbladder.
F
What gland is near the maxillary sinus and may regulate mucous viscosity in the nose?
Steno’s gland
Describe the female uterus in rats.
2distinct ossa uteri and cervices
What is characteristic of the cerebrum in rats and mice?
Lissencephalic (no sulci/gyri)
What sits behind the optic chiasm in the rat and is attached by an infundibular stalk to the brain?
pituitary hypophysis
T/F: Rats have a foramen of Magendie.
F.
What is special about atrial blood supply in rats?
It is mostly extracoronary (unlike most mammals)
Most common circulating blood leukocyte in rats?
lymphocyte
What type of diet formulation is accessible to the public?
open formula
What type of diet formulation is NOT accessible to the public?
closed formula
What is a certified diet?
Diet assayed to not exceed a max concentration of certain contaminants that may influence study results
What are the 4 pathways mediating calorie restriction?
(1) IGF-1/insulin signaling pathway
(2) sirtuin pathway
(3) AMP-activated protein kinase (AMPK) pathway
(4) TOR (target of rapamycin) pathway
When does the vaginal plate open in rats?
40-50d
When is puberty in the rat?
40-60d
How long is the rat estrus cycle?
4 days
How long is rat gestation?
21-23d
How much do rats eat/day?
5% of BW/day
How much do rats drink per day?
8-11% of BW/day
What are 2 ways to detect estrus in rats?
Vaginal cytology
Electrical impedence
When is the earliest GD to palpate rat fetuses transabdominally?
10d
Chronic exposure to low light levels results in what peripubertal change/
Earlier vaginal opening, ovarian atrophy
What husbandry parameter may contribute to male infertility?
high ambient temperatures- irreversible
What is pregnancy wastage?
Fetal loss occuring during pregnancy
When do incisors erupt in rats?
6-8d
When are pups fully haired?
7-10d
When are rat pups first able to hear?
9d
When do eyelids open in rats?
14-17d
When is the micturition reflex mature in rats? Significance?
15d- need stimulation to urinate prior to this
How are embryos preserved prior to implantation into a recipient?
PBS and fetal calf serum
When are embyros collected for manipulation?
1-5d after breeding
What test differentiates alpha-hemolytic Strep pneumoniae vs other alpha-hemolytic Step samples?
optochin inhibition test- Strep pneumo is inhibited, others aren’t
Characteristic fibrinopurulent polyserositis is seen with what bacterial etiology in rats?
Strep pneumoniae
What pathologic findings are seen with Strep pneumoniae in rats?
inflammation of upper respiratory tract- rhinitis, sinusitis, conjunctivitis, pleuritis, bronchopneumonia, vestibular dz
What pathogenic serotypes of Strep pneumo are found in rats?
2,3,8,16,19
How is Strep pneumo diagnosed in rats?
Histopath + culture of nasopharyngeal swab on blood agar or PCR of lung/nasopharyngeal swab
What bacteria produces pseudomembranous colitis in germ-free rats?
C. difficile
What bacteria is associated with adenocarcinomas in Wistar rats?
Lawsonia intracellularis
What is the causative agent of streptococcal enteropathy in stunted suckling rats?
Lancefield Group D enterococci
Causative agent of pseudotuberculosis?
Corynebacterium kutscheri
Species that C. kutscheri affects?
Rats, mice, GPs, hamsters
What organ is most commonly affected by C. kutscheri in rats?
lung
What type of inflammation is seen in pseudotuberculosis?
suppurative inflammation with caseous necrosis
How is pseudotuberculosis controlled?
Rederivation and bioexclusion
How is pseudotuberculosis diagnosed?
PCR of LN, oropharynx, nasopharynx, preputial glands, feces
Causative agent of Tyzzer’s?
Clostridium piliforme
What triad of organs are affected by C. piliforme?
Intestine, heart, liver
What stains are used to identify C. piliforme?
Warthin-Starry, H&E, Giemsa, methylene blue stain
What is the hallmark lesion of Tyzzer’s dz in rats?
coagulative necrosis of the liver
What clinical signs are seen with Leptospirosis infection in rats?
None- silent carriers
How is Pasteurella pneumotropica diagnosed in rats?
culture/PCR screening
How is P. pneumotropica treated in rats?
enrofloxacin + rederivation
What Salmonella is usually seen in rats?
S. enterica
What pathology is seen with Salmonella infection in rats?
mural thickening, mucosal ulcers in cecum and ileum
splenomegaly
white foci on liver
How is Salmonella diagnosed in rats?
Culture of mesenteric lymph nodes at nx
PCR of feces
What type of rats have a high incidence of Staph aureus- associated ulcerative dermatitis?
Beige rats w Chediak-Hegashi syndrome (NK cell deficiency)
What organ is most affected by Pseudomonas aeruginosa in immunocompromised rats?
lung
How is Pseudomonas aeruginosa treated in rats?
Gentamycin
Chlorinate/acidify water
Improve environment
What is the causative agent of rat bite fever?
Strep moniliformis
Spirillum muris in Asia
How is Strep moniliformis transmitted in rats?
excreted in blood and urine
transmitted by bites, aerosol, fomites
What are the two most common Helicobacters id’ed in rats?
H. muridarum
H. trogontum
How is Helicobacter diagnosed in rats?
PCR
How is CAR bacillus transmitted?
Direct contact
What pathology is seen with CAR bacillus infection?
suppurative bronchopneumia
What stain can be used to ID CAR bacillus?
Warthin-starry
Methenamine silver
How is CAR bacillus diagnosed?
Serology + confirmatory Steiner stain of tracheal mucosal scraping
PCR of nasal swab
What is the cause of respiratory mycoplasmosis in rats?
Mycoplasma pulmonis
How is M. pulmonis transmitted?
direct contact, aerosol, in utero
What clinical signs are associated with respiratory mycoplasmosis?
dyspnea, snuffling, chattering, oculonasal discharge, chromodacryorrhea, eye rubbing
Also: head tilt, infertility, arthritis
What disease is associated with ‘cobblestone lung’ on gross necropsy?
respiratory mycoplasmosis
What is the best method of diagnosing mycoplasmosis in rats?
PCR of affected site or nasopharyngeal wash
What is the primary cause of early mortality in conventional or non-SPF rat colonies?
respiratory mycoplasmosis
What is the causative agent of hemobartonellosis in rats?
Mycoplasma haemomuris
How is Mycoplasma haemomuris transmitted?
spiny rat louse (Polyplax spinulosa)
What organ is needed to clear infection with Mycoplasma haemomuris?
spleen
What bacteria is associated with impaired ciliary clearance in multiple species and may lead to bronchopneumonia?
Bordetella bronchiseptica
How is Mycoplasma haemomuris treated?
Rederivation
What family is Sendai virus from?
Paramyxoviridae
What genus is Sendai virus?
Respirovirus
How is Sendai transmitted?
aerosol, direct contact
What rat strains have the most severe lesions with Sendai?
BN, LEW
What is the best method for diagnosing Sendai?
MFIA, then IFA and WB to confirm for monitoring
PCR of trachea and lungs for active infection
What is the best way to prevent inadvertent introduction of Sendai into a colony?
PCR on all transplantable biological materials
Quarantine with serologic testing
How is Sendai eliminated from rat colonies?
cease breeding and don’t introduce new mice; burnout in 4-8w
What two types of coronaviruses are found in rats?
Parker’s rat coronavirus
sialodacryoadenitis virus
Are rats infected with one coronavirus protected against infection with the other?
No- antigenic differences result in no cross-protection
How are coronaviruses transmitted in rats?
aerosol, direct contact, fmoites
What tissue tropisms do rat coronaviruses have?
salivary glands, lacrimal glands, Harderian glands, respiratory epithleium
How do endemic infections with coronavirus pressent?
mild conjunctivitis in pre-weaning rats
how do epizootic infections with coronavirus present?
cervical swelling d/t salivary gland edema, oculonasal discharge, photophobia, corneal opacity or ulceration
How long do clinical signs last with sialodacryoadenitis virus?
7-10 days, reparative process takes ~4w
What clinical signs are associated with nude rats affected by coronavirus?
persistent infection with wasting
How is an outbreak with rat coronavirus controlled?
Allow virus to spread through colony, prevent new entries and allow to burn out for 6-8w
What 4 parvovirus serotypes infect rats?
(1) Kilham’s rat virus (RV)
(2) Toolan’s H-1 virus
(3) Rat parvovirus (RPV)
(4) Rat minute virus (RMV)
What is the most pathogenic parvovirus in rats?
Kilham’s rat virus (RV)
What is the most prevalent virus in domestic rat colonies?
Rat parvovirus
What is the parvovirus species?
Rodent protoparvovirus 1
Rat parvovirus has a tropism for what tissue?
Lymphoid
How is rat parvovirus transmitted?
urine/milk, aerosol, direct contact, fomites, transplacental
Reduced litter size, runted litters, fetal death, and cyanotic scrotum are associated with what very common rat virus?
rat parvovirus
Scrotal hemorrhage and cerebellar hypoplasia with intranuclear inclusions are associated with what disease in rats?
rat parvovirus
PCR for what component of rat parvovirus is cross-reactive with multiple serotypes?
NS1
PCR for what component of rat parvovirus is highly specific for each serotype?
VP2
What genus is Theiler’s murine encephalomyelitis virus in and what rat virus is is related to?
Cardiovirus
rat theilovirus
Where does rat theilovirus replicate
small intestinal enterocytes
Experimental injection with which theilovirus strain induces paralysis in weanling rats?
MHG
What is the best way to diagnose rat theilovirus?
serology best
PCR of feces/intestine for active infection
What is the reservoir host for group B rotavirus in rats?
humans (eww)
Epithelial syncytia in the small intestine of infant rats is pathognomonic for what disease?
group B rotavirus
Pneumonia virus of mice is in what family?
Paramyxoviridae
Pneumonia virus of mice is diagnosed how in rats?
serology, PCR of trachea/lungs for active infection
How is hantavirus diagnosed in rats?
serology
Norway rats are natural hosts for what type of hantavirus?
Seoul
Cotton rats are the primary reservoir for hantaviruses resulting in what syndrome?
Hantavirus pulmonary syndrome
Seoul and Hantaan virus result in what syndrome in humans?
hemorrhagic fever with renal syndrome
Hantavirus has a tropism for what tissues?
vascular smooth muscle, endothelium
What is the reservoir of cowpox virus in Europe?
wild rats
What are the 3 most significant protozoal diseases in rats?
Giardia
Spironucleus
Encephalitozoon
Rats are the intermediate host for what apicomplexan parasite that affects cats?
Toxoplasma gondii
What is a significant side effect of treatment with metronidazole in rats and mice?
carcinogenic, teratogenic
What is the most common oxyurid of rats?
Syphacia muris
How is S. muris differentiated from Syphacia obvelata?
Syphacia muris slightly smaller with longer tail and smaller eggs that are only slightly flattened on one side
How long is the life cycle of Syphacia?
11-15d
How long is the life cycle of Aspicularis?
23-25d
How is Aspicularis diagnosed?
fecal float, PCR, intestinal contents
How is Syphacia diagnosed?
PCR, tape test, intestinal contents
How are Aspicularis and Syphacia treated?
fenbendazole, ivermectin, avermectin, levamisole
What nematode infests the urinary bladder of rats?
Trichosomoides crassicauda
How is Trichosomoides crassicauda diagnosed?
urine filtration + exam of filter medium antemortem
postmortem by exam of bladder wall + histopath
How is Trichosomoides crassicauda treated?
ivermectin
What are the two most important cestodes in rats?
Rodentolepis nana
Hymenolepis diminuta
What cestode can have a direct OR indirect life cycle?
Rodentolepis nana
How do you differentiate H. diminuta from R. nana?
R. nana have a polar filament and hooked rostellum on adults
Cysts of Taenia taeniaformis on the liver are associated with what sequela?
hepatic sarcoma
Where is R. nana found in the GIT?
SI
What immune response is elicited by infection with cestodes?
host Th2 type immune response
What is the most common fur mite in rats?
Radfordia ensifera
What clinical signs are seen with fur mites in rats?
Pruritis, 2’ bacterial infection
What is the most sensitive way to diagnose fur mites?
PCR
How are fur mites treated in rats?
Selamectin, cross-fostering, rederivation
What immune response is elicited by infection with fur mites?
host Th2 immune response resulting in elevated IgE
What are two blood sucking mites that live in the environment and are only found on rats during feeding?
Ornithonyssus bacoti
Laelaps echidnina
What is the most common rat louse?
Polyplax spinulosa
What fungal organism causes uncontrolled proliferation of foamy material in the alveoli when it infects immunocompromised mice?
Pneumocystis carinii
What stain is used to identify Pneumocystis carinii?
methenamine silver stain
What disease is caused by Pneumocystis carinii?
interstitial pneumonia
How is Pneumocystis carinii diagnosed?
PCR of lung tissue, serology 6-8w after infection
P. carinii infection in rats is a model of what disease?
P. jirovecii pneumonitis in humans
What are 3 rat models of hypertension?
SHR
Fawn-hooded
Dahl salt-sensitive
A high incidence of eosinophilic granulomatous pulmonary inflammation is found in what rat strain?
brown norway
What is the primary use of brown norway rats?
allergy and asthma
Polyarteritis nodosa is found in what two rat strains?
Sprague-Dawley
SHR
What organ is NOT affected by polyarteritis nodosa in rats?
lung
High light levels can result in what 3 conditions?
Retinal degeneration
Harderian gland necrosis
Infertility
Chloral hydrate administration results in what condition?
adynamic ileus up to 5w after administration
What anesthetic combination results in corneal lesions due to vasoconstriction of ciliary and iridial vessels?
ketamine-xylazine
NSAIDS result in what sequelae?
renal papillary and tubular necrosis
What is the most common tumor type in rats?
mammary tumors
What type of rat has the highest incidence of mammary gland tumors?
SD
Also F344, Wistar Han
Interstitial cell tumors are found most often in what rat?
F344
Pituitary gland tumors are seen most often in what rats?
SD, F344, Wistar Han
Pituitary gland tumors are most often what origin?
Chromophobe adenoma from pars distalis
Prolactin-producing most common
What type of adrenal gland tumor is most common in rats?
pheochromocytoma
What is a major cause of death in F344 rats?
large granular lymphocytic leukemia
What type of rat is prone to mesothelioma?
F344
What is the most common congenital abnormality in rats?
hydronephrosis
What rat strain has the highest incidence of congenital hydronephrosis?
Gunn (dominant inheritance)
Wistar-kyoto rats have a high incidence of what congenital abnormalities?
ventricular septal defects, right ventricular hypertrophy
What is the primary use of Wistar-kyoto rats?
control for outbred SHR rats
What rat is used as a model of audogenic seizures?
Wistar
What rat type has a predisposition to corneal mineralization?
F344
The testicular-feminized rat is prone to what condition?
tfm is gene
see male pseudohermaphroditism
What is one of the most common causes of death in rats on long-term/lifetime studies?
chronic progressive nephropathy
What sequela of CPN leads to dystrophic mineralization?
Secondary hyperparathyroidism
What gender and type of rat most commonly get CPN?
male SD, F344
Pitting of the cortical surface of the kidney in aged rats is most often due to what condition?
CPN
Nephrocalcinosis is seen most often in what rats?
female F344, BDIX
What is deposited in the tissues with nephrocalcinosis?
calcium phosphate at the renal corticomedullary junction
UTIs are most common in what type of rat?
Zucker Diabetic Fatty rat
What is a major cause of death in ad lib-fed SD males?
chronic myocardial disease
What are gross lesions characteristic of chronic myocardial disease?
ventricular hypertrophy, pale streaks
Age-associated hair loss is most common in what type of rat?
BN
T or F: Rats show the Whitten and Bruce effect.
F
When does implantation of the blastocyst occur?
5 days
How many pairs of mammary glands do rats have?
6
Reflexive withdrawal from noxious stimulation is observed as early as what embryonic day in the rat?
a. E14
b. E15
c. E16
d. E17
e. E18
d. E17
