Laboratory Rodents Flashcards
1
Q
Which organ has its medium sized arteries spared in polyarteritis nodosa? a. kidney b. mesentery c. pancreas d. lung
A
D. lung
2
Q
Which strains of rats are predisposed to polyarteritis nodosa?
A
SD and spontaneous hypertension rats (SHRT); any rat with late stage CPN
3
Q
What are two differentials for a mouse with a head tilt?
A
necrotizing arteritis and mycoplasma otitis –> ischemic necrosis of inner/middle ear
4
Q
Which of the following is the key feature of Sialodacryoadenitis Virus? a. nonkeratinizing squamous metaplasia of ductal and acinar structures of the Harderian gland b. keratinizing squamous metaplasia of ductal and acinar structures of Harderian gland c. chromodacryorrhea d. ductal epithelial hyperplasia of the Harderian gland
A
a. nonkeratinizing squamous metaplasia of the ductal and acinar structures of the Harderian gland. Also coagulative to lytic necrosis of ductal epithelium, inspissated porphyrin and neutrophilic infiltrates
5
Q
Which mouse strain is the most susceptible to Sendaui virus? a. C57BL/6J b. NOD c. BALB/cJ d. DBA
A
d. DBA
6
Q
Necrotizing rhinotracheitis with intracytoplasmic inclusions, syncytia and type II pneumocyte hyperplasia are all common features of which disease in mice? a. Sendai virus b. Sialodacryoadenitis virus c. Ectromelia virus d. Respiratory strains of Mouse Hepatitis Virus
A
a. Sendai virus - infects resp. epithelium, middle ear epi, type II pneumocytes. Causes a perihilar to cranioventral to diffuse consolidation of lungs. Syncytia are also found in MHV but are in multiple organs, have a vasculocentric pattern and do not have the epitheliotropism of Sendai. Ectromelia is mouse pox and SADV affects the Harderian gland with potential secondary bacterial pneumonia.
7
Q
All of the following are factors in developing Ringtail in mice except: a. high temperature b. low humidity c. inherited cornification disorders d. aged mice
A
d. old age. Young mice are predisposed to the disorder
8
Q
Which bacteria is frequently co-infected with Filbacterium rodentium? a. Mycoplasma pulmonis b. Corynebacterium kutscheri c. Pseudomonas aeruginosa] d. Pasteurella multocida
A
a. Mycoplasma pulmonis
9
Q
The mechanism of disease for filobacterium rodentium is? a. impaired mucociliary clearance b. necrosis of tracheal epithelial cells c. pulmonary abscess formation d. vascular degeneration
A
a. impaired mucociliary clearance. Necrosis of tracheal epithelial cells is in Sendai virus. C. kutscheri forms abscesses. Vascular degeneration is in Mouse Hepatitis Virus.
10
Q
Tissue from a mouse. Which of the following is the most likely etiology?
A. C. kutscheri
B. M. pulmonis
C. F. rodentium
D. P. multocida
A
A. C. kutscheri is part of YAACSS and makes clouds of bacteria in its abscesses
11
Q
The compound found in these are primarily:
a. Ym1 Chitinase
b. Major Basic Protein
c. Hemosiderin
A
A. Ym1 chitinase are the component of crytals in acidophilic macrophage pneumonia. They are rhomboid shaped and eosinophilic as opposed to the dark red hemoglobin crystals associated with hemorrhage. They are commonly found secondary to pulmonary tumors, pneumocystis, or chronic pneumonia and are most common in older B6, 129 and Swiss mice.
12
Q
Tissue from a rabbit. Morph only.
A
Renal lymphoma. Kidney is primarily involved in rabbits.
13
Q
Tissue from a guinea pigs. Name the disease and cause.
A
Lumps; similar to strangles. Caused by Streptococcus equi var. zooepidemicus. Morph would be bilateral suppurative submandibular lymphadenitis. Commensal in guinea pigs mouth and tropsim for LN’s of the head and neck. Can rupture and form abscesses in other organs.
14
Q
Mouse. Name the condition.
A
Cutaneous horn. Likey caused by a murine papillomavirus.
15
Q
Gerbil. Morph.
A
Adenocarcinoma of the ventral marking gland of the gerbil. Modified sebaceous glands. Hamsters have paired marking glands on either side of their lumbar spine, also they process testosterone. Gerbils have single marking gland on central abdomen, no other function but marking.
16
Q
Tissue from a mouse. Cause and another organ affected. What is a resistant strain?
A
Murine poxvirus ( or ectromelia virus). Splenic and hepatic necrosis. C57/B6 is resistant.
17
Q
Tissue from a rat. Name the disease, give the morph. Key histologic feature. What is another species that gets similar lesions? What strain of rat gets this spontaneously?
A
Polyarteritis nodosa. Multifocal to coalescing necrotizing and proliferative mesenteric arteritis. Fibrinoid necrosis of vessels. Beagles - beagle pain syndrome. SHR or spontaneous hypertensive rate.
18
Q
Tissue from a ferret. Morph.
A
Caudal vertebral chordoma. Tail most common site, next most common is cervical vertebrae.
19
Q
Tissue from a rat. Morph. Cause. Name another affected organ.
A
suppurative bronchopneumonia with bronchiectasis. Mycoplasma pulmonis = think cilia. Other affected organs are uterus, tympanic bullae (other ciliated areas). Not in joints in rats. Mycoplasma superantigens create lymphoid hyperplasia.
20
Q
Hamster. Morph and cause.
A
Trichoepitheliomas from hamster polyomavirus-1.
21
Q
Tissue from a guinea pig. Etiology?
A
Strep equi var. zooepidemicus. Causes cervical lymphadenitis. Name is “Lumps” disease.
22
Q
What is the receptor for Mouse Hepatitis Virus?
A
CEACAM
23
Q
Enterotropic MHV is also known as ________. What is a classic gross and histo lesion?
A
lethal intestinal virus of infant mice; lack of milk spot, villous bluting of intestine with SYNCYTIA OF VILLOUS TIPS
24
Q
What is the most common clinical sign of murine norovirus (calicivirus) in mice?
A
nothing
25
Which gene defects result in clinically apparent murine norovirus disease?
STAT null mice and IFN-y null mice
26
What gene defects can lead to inability to clear murine norovirus?
STAT, IFN-y or RAG null mice. Either innate or adaptive immune deficit will lead to inability to clear it.
27
Epizootic diarrhea of infant mice (EDIM) is caused by \_\_\_\_\_\_\_\_\_? What is the histo lesion?
rotavirus; villous blunting without syncytia of MHV but has apical vacuolar degeneration of enterocytes.
28
Murine minute virus causes what clinical disease?
nothing!minute virus causes minute changes; cleared readily
29
Tissue from a mouse.Most likely etiology and potential sequelae?
Mouse chapparvovirus. Causes CKD over time.
30
Lactate dehydrogenase virus, an arterivirus, causes poliomyelitis in what strains of mice?
A. BALB/c
B. C3H
C. NSG
C. NSG mice exposed to LDV develop poliomyelitis in those mice that also have the Fv(1)n allele.
31
What paramyxovirus causes BALT hyperplasia, syncytia, intracytoplasmic and intranuclear inclusions, and squamous metaplasia in immunocompetent mice?
Sendai virus
32
Tissue from a mouse.What tissues are you most likely to see this in?
salivary gland, pancreas or kidney. Murine cytomegalovirus. Model for human congenital malformations.
33
What are 5 differentials for this lesion?
34
Tissue from a mouse. Etiology?
Ectromelia virus.This is splenic fibrosis from previous necrosis.
35
Rectal prolapse secondary to chronic typhlocolitis is a sequela of what etiologies in mice?
Helicobacter spp.; Citrobacter rodentium; Mouse Hepatitis Virus in susceptible strains; Mouse norovirus in STAT-/- or IFNy-/-
36
A cause of pronounced colonic hyperplasia in mice is?
Citrobacter rodentium, also causes "hose pipe"colon, thick and short.
37
Tissue from a mouse.2 viral causes and2 bacterial causes.
Ectromelia virus (pox), and MHV (corona). Hepicobacter hepaticus and C. piliforme (Tyzzer's).
38
Tissue from a mouse. Etiology and 2 other affected organs.
This is Tyzzer's disease caused by Clostridium piliforme. Hepatic necrosis with target lesion is classic.Also causes necrosis in heart and intestines (triad).
39
This commensal of the mouse respiratory tract commonly causes retroorbital abscesses in SCID mice.
Rodentibacter pneumotropica, heylii. Also causes subQ abscesses in any mouse, and pneumonia in immunocompromised mice. Also causes conjunctivitis in any mouse.
40
Tissue from a rat. Etiology?
Mycoplasma pulmonis. Typical cobblestone appearance of the lung.
41
Tissue from a rat. Etiology?
Filobacterium rodentium. CARbacillus.
42
Tissue from a mouse. Expected histologic finding.
Gram positive cocci with Splendore-Hoeppeli material, abundant neutrophils surrounded by epitheliod macrophages and then fibroblasts. Staph aureus.Botryomycosis.
43
Tissue from a mouse. Etiology? Significance for the facility?
Hymenolepis nana, rodent dwarf tapeworm with characteristic polar filaments and 3 hooks. This is zoonotic!
44
Tissue from a mouse. Etiology? What is the clinica significance.
A. Myocoptes musculinis
B. Radforida affinis
C. Radfordia ensifera
D. Myobia musculi
D. This is Myobia musculi, fur mite of mice. Has "bulging muscles" which differentiate it from Myocoptes musculinis which is chunky. Causes immune sensitization where M. musculinis does not. Radfordia affinis also has a bulging muscles look to it, but has two unequal claws on its second legs. R ensifera is in rats.
45
Tissue from a mouse. Etiology?
A. Ornithonyssys bacoti
B. Demodex gatoi
C. Psororgates simplex
D. Polyplax serrata
D. Polyplax serrata. This is the common louse of lab mice. A is the tropical rat mite, B. is not found in mice, C. is a follicular mite related to psorpotes. Polyplax serrata causes erythema, pruritis, anemia. Has been a vector for Mycoplasma coccoides (RBC parasite) and Francisella tularensis.
46
What is the significance of Oxyuris (Syphacia obvelata/muris and Aspiculuris tetraptera) infection in mice and rats in laboratory facilities?
Pinworms cause a Th2-skewing of immune system.
47
Tissue from a mouse. Special stain helpful in diagnosis?
A. Gram stain
B. Luna
C. GMS
D. Giemsa
C. GMS. This is the common appearance of Pneumocystis murina infection in an immunocompromised mouse. In immunocompetent mice, the disease is usually transitory. Best appreciated with a GMS or PAS stain, also IHC.
48
A gross differential diagnosis for Trichophyton mentagrophytes in mice is:
A. Staphylococcus aureus
B. Corynebacterium bovis
C. Polyplax serrata
D. Syphacia obvelata
B. Corynebacterium bovis is a good differential for ringworm in mice caused by Trichiphyton mentagrophytes. Causes local crusted, chalky lesions. Ring lesions not common. Is NOT autoflourescent.
49
Tissue from a mouse. Histologic features of hepatic necrosis and cytoplasmic invagination are common with infection of what bacteria? What is a potential sequelae if this mouse is an A strain mouse?
Helicobacter hepaticus or H. rodentium. Also causes proliferative typhlocolitis along with hepatic necrosis, cholangitis, bile duct hyperplasia. LESIONS ONLY FOUND IN IMMUNODEFICIENT MICE (A/JCr, SCID/NCr, BALB/cANCr, C3H/HeNCr, and SJL/NCr). In A strain mice, hepatocellular carcinomas can develop from infection.
50
What is unique about Sendai virus?
It can cause disease in immunocompetent mice.
51
Which strains of mice are predisposed to this lesion?
DBA, BALB/c, C3H
52
Fatty liver in micecan bea result of deficiency of what?
choline
53
This lesion can be associated with what causes?
cilia gene defects, theiler's murine encephalomyelitis virus, polyoma virus, reovirus, LCMV (the zoonotic one!)
54
Clown mouse syndrome, pictured here, is associated with infection and recovery from what disease?
mouse hepatitis virus
55
This lesion is commonly secondary to what?
imperforate vagina - leads to muco/hydrometra.
56
This lesion is mediated by which complement protein?
C3 - membranoproliferative glomerulonephritis;commonly causes ascites/anasarca in mice
57
This condition in a mouse is called _________ and the material is \_\_\_\_\_\_\_\_\_.
hyaline glomerulonephropathy; NOT amyloid, PAS positive. basement membrane expansion. Comparable to CPN in rats.
58
This lesion in the middle or inner ear of a mouse is called \_\_\_\_\_\_\_\_is known for causing this clinical sign?
vestibular syndrome or polyarteritis; head tilt/circline/imbalance. Lesions in other tissues such as kidney.
59
What type of lymphoma is most common in mice?What is a DDx?
Follicular B cell lymphoma; mature lymphomas are more common in mice \> 12 months of age. DDx is diffuse large B cell lymphoma.
60
Most likely etiology?
myoepithelioma. DDx would be mammary tumor, salivary gland tumor. Frequently myoepitheliomas are cystic and have both epithelial and mesenchymal differentiation.
61
Tissue from a mouse. Morph.
Harderian gland adenoma.
62
Name the disease and give 3 potential causes.
Mutlifocal ulcerative dermatitis of B6 mice. Genetic causes, ectoparasite sensitivity, secondary bacterial infection, immune mediated leukocytoclastic vasculitis.
63
Etiology? Histo lesions?
Ectromelia virua (pox virus). Histo lesion is balloon degeneration, ulceration, hyperplasia. eosinophilic intracytoplasmic inclusions. B6 mice are resistant! Intermediate susceptibility mouse strains required for cutaneous lesions to develop, otherwise die acutely.
64
2 etiologic differentials and one predisposing factor.
Corynebacterium bovis or Staphylococcus xylosus; immunodeficiency (not hairlessness). Also consider cutaneous lymphoma with secondary infection.
65
Name the disease and give two etiologies.
Botryomycosis. S. aureus or P. aeruginosa.
66
Morph and 3 causes.
Cutaneous papillomas. Murine papillomavirus. Genotype. Carcinogens.
67
Tissue from a rat. Morph?
Keratoacanthoma.
68
Morph and 2 causes.
Ascites/anasarca. Glomerulonephropathy, glomerular or intestinal amyloidosis. Atrial thrombosis,
69
Morph and 3 causes.
Focal lateral femoral hernia,; Estrogen treatment in males, androgen treatment in females, FVB substrain.
70
Tissue from a mouse. Morph and 3 causes.
Mammary lobuloalveolar hyperplasia. Causes: pregnancy, prolactinoma of pars distalis, FVB strain.
71
Morph and 3 Possible causes.
Mammary adenocarcinoma; carcinogens, mouse mammary tumor retrovirus, hormones, strain.
72
Tissue from a rat. This lesion is associated with:
A. Malignant transformation
B. Retrovirus induction
C. High tubule:stroma ratio
D. Fibroblast proliferation
D. This is a mammary fibroadenoma in rat, which are benign and not associated with retroviruses like they are in mice.
73
Tissue from a rat. Morph and histo feature. What strain of rat are these most common in?
Zymbal's gland carcinoma. This is a modified sebaceous gland with ducts lined by keratinized squamous epithelium. Variable proportions of sebaceous and squamous cells. Differentials on histo are squamous papillomas of zymbal's gland and SCC of adjacent tissue. Gross DDx is mammary tumor. F344 rats have the highest incidence but they occur in all rats, not common at all in mice.
74
Morph. 4 differential etiologies. Histo features.
Preputial gland abscess, bilateral. Caused by Rodentibacter pneumotropicus; Klebsiella oxytoca; Staphylococcus spp.; Streptococcus spp. Ducts lined by squamous epithelium, eosinophilic granular material in glands is normal, abundant neutrophils.
75
Name the condition. Give 3 causes. What is the pathogenesis?
Ringtail. Genetics (epidermal differentiation genes); low humidity; high temperature; hydration status.
Pathogenesis: Disordered cornification --\> hyperkeratosis, abnormal desquamation --\>persistent keratin ring --\> strangulation --\> gangrenous necrosis.
76
Tissue from an FVB mouse. Other location for this lesion and histo features.
This is a dermal coccygeal neural crest tumor. Pinna of the ear is the other common lesion. See image for histo (Schwannoma-looking).
77
Tissue from a mouse. Morph and cause.
Auricular chondritis. Cause is hypersesntivity reaction to copper and iron released from ear tags.
78
Tissue from a mouse. Morph and cause.
Aural squamous papilloma. Murine papillomavirus.
79
Tissue from a rat. Morph and etiology.
Suppurative otitis media/interna; mycoplasma pulmonis
80
Tissue from a mouse. Morph and strain most susceptible.
Microphthalmia, unilateral. C57BL/6 mice most susceptible.
81
3 causes of cataracts in mice are:
aging, irradiation, genetics (C57BL/6 mice, B6C3F1)
82
Tissue from a mouse. Name the condition and give 3 causes.
Calcific band keratopathy.
Predisposing cause: Anesthesia (ketamine inhibits blink response), environmental ammonia, mechanical irritation.
83
Tissue from a mouse. Morph and potential cause.
hyphema. SDAV induced lacrimal damage.
84
Tissue from a mouse. Morph and 3 causes.
ulcerative blepharoconjunctivitis.
Cause: Corynebacterium kutscheri; Staphylococcus spp., Streptococcus spp.; Streptobacillus moniliformis; Rodentibacter pneumotropicus; Pseudomonas aeruginosa.
In nude mice, can be caused by the lack of eyelashes. They have hairfollicles but they break off before they emerge.
85
Etiology?
SDAV (coronavirus). This picture is harderian necrosis from SDAV.
86
Morph.
Harderian gland adenoma with exophthalmia.
87
Morph and 3 causes.
Morph Dx: Bilateral tibiotarsal suppurative arthritis.
Cause: Corynebacterium kutscheri; Streptobacillus moniliformis; Mycoplasma pulmonis.
88
Which strain of mouse has a background lesion of vertebral osteosarcoma, with caudal vertebra having the highest rate of metastasis?
NOD and NOD derived mice (NSG)
89
Tissue from a mouse. Morph and pathogenesis.
Morph Dx: Left auricular thrombosis.
Pathogenesis: Amyloidosis --\> proteinuria and hypoproteinemia --\>loss of antithrombin III --\> auricular thrombosis.
Note: Common cause of dyspnea.
90
Tissue from a rat. Two potential causes.
Mycoplasma pulmonis \>\> Filobacterium rodentium (new name of CARbacillus).
91
Tissue from a rat. Morph and a cause.
Embolic pneumonia. Corynebacterium kutscheri.
92
What is a common underlying genetic mutation in mice with primary lung neoplasms?
KRasmutations. Usually A strains, 129 strains.
93
What is a common secondary change in lungs with primary neoplasms?
acidophilic macrophage pneumonia
94
What is the protein responsible for the eosinophilic nature of acidophilic macrophage pneumonia?
Protein identified as **chitinase-3-like 3 (Chi3l3)** [formerly Ym-1 (AKA eosinophil chemotactic factor) and Ym-2] which is a unique functional marker for alternatively activated macrophages in Th2-mediated inflammation.
95
Associated clin path finding?
lower cholesterol and higher triglyceride in fluid than blood; [Fluid Cholesterol] / [Fluid Triglyceride] = \<1.0.
96
Tissue from a rat. Etiology?
Streptococcus pneumoniae. See fibrin, think Strep.
97
Tissue from a rat. Morph. Cause. Histo feature.
Salivary adenitis with edema and necrosis, SDAV, squamous metaplasia.
98
Tissue from a mouse. Top DDx. Associated condition and most susceptible strain.
salivary gland myoepithelioma. Associated condition: Myeloid hyperplasia of bone marrow.
Note: Common nonthymic tumor in SCID mice.
99
Tissue from a young rat. Cause?
rat adenovirus.
100
Which parvovirus of rats can cause testicular necrois and scrotal hemorrhage? What does it cause in prenant females?
Kilham rat virus,; fetal resporption and cerebellar hypoplasia
101
What virus causes syncytia in the intestinal epithelium of infant mice?
Mouse Hepatitis Virus
102
Tissue from a rat.Etiology?
Clostridium piliforme causes megaloileitis in rats.
103
Diarrhea in rat pups can be caused by:
Cryptosporidium parvum or Rotavirus.
104
The threadworm of rats is:
Strongyloides ratti
105
Syphacia muris is also known as \_\_\_\_\_\_.
pinworms; infects both rats and mice
106
Tissue from a rat. Etiology?
Hymenolepis diminuta
107
Catarrahl enterititis in rats is caused by what tapeworm of rats?
Rodentilepis nana
108
Renal tumors arise spontaneously in what strain of rat?
Eker rat
109
What IHC's are used for nephroblastoma diagnosis?
WT1 and PCNA (both positive)
110
Urinary bladder tummors are associated with what organism in rats?
Trichosomoides crassicauda
111
Granular cell tumors in rats occur in what two common locations?
vagina and brain
112
Lymphocytic choriomeningitis virus occurs in ____ but not \_\_\_\_\_\_\_.
mice; not rats
113
114
Wistar rats commonly develop what neoplasm?
A. Pituitary basophil adenoma
B. Mammary carcinoma
C. Pheochromocytoma
D. Hepatoblastoma
C. Pheochromocytomas are very common in Wistar rats, and common in other rat strains
-most pituitary tumors are chromophobe adenomas so basophil adenomas, mammary carcinoma is rare (mammary fibroadenomas most common) Hepatoblastomas are rare
115
Fisher 344 (F344) rats are known for developing which tumors most commonly?
A. Large granular cell leukemia and Interstitial testicular tumors
B. Pheochromocytomas
C. Endometrial carcinoma and lymphomas
D. Polyarteritis
A. Large granular cell leukemia and interstitial testicular tumors
- pheochromocytoma are known best in Wistar rats
- lymphomas and endometrial carcinoma are in Lewis rats
- Polyarteritis can form nodules, but is not a neoplasm and is best seen in SHR (Spontaneous Hypertensive)
116
Urothelial carcinoma in the bladder is associated with?
A. Brown Norway, *Trichosomoides crassicauda*
B. Sprague-Dawley, Pituitary tumors
C. *Laelaps echidnina*
D. *Notoedres muris*
A. Brown Norway rats are predisposed to spontaneous urinary tract carcinoma (strain also known for asthma model). *Trichosomoides crassicauda bladder threadworm* parasite is associated with proliferative bladder lesions, urolithiasis, and neoplasms!
* Laelaps echidnina* - is the spiny rat mite, transmits *Hepatozoon* sp.
* Notoedres muris* is the ear mange mite causes proliferative dermatitis on pinnae, legs, tail
117
Dahl Salt Sensitive (DSS1-3) rats are most prone to what clinical and pathological disease?
hypertension and cardiomyopathy on high salt diet
also obesity, hyperinsulinemia, and hyperlipidemia
118
Eker rats are known for hereditary renal cell carcinoma due to?
## Footnote
A. WT1 (Wilms tumor 1)
B. PPIB (Peptidylprolyl Isomerase B)
C. TSC2 (tubular sclerosis 2)
Insertional mutation in Tsc2 (tubular sclerosis 2) tumor suppressor gene
WT1 wilms tumor 1 marker on IHC for nephroblastomas in rats, dogs, etc
PPIB is gene mutation in HERDA horses (quarter horses with regional dermal asthenia, stretchy skin)
119
BioBreeding Rat (BB-DP and BB-DR) are diabetes prone due to?
A. lymphocytic thyroiditis
B. lymphocytic destruction of beta cells
C. lymphocytic destruction of alpha cells
D. lymphocytic destruction of delta cells
B. lymphocytic destruction of beta cells! Beta cells produce insulin, so their destruction contributes to pathogenesis of insulin-dependent diabetes mellitus (develops about 60-120 days, they are prone to ketosis, so must be similar to type I diabetics)
BB-DP BB-DR rats are also prone to lymphocytic thyroiditis but that does cause diabetes
in the pancreatic islets alpha cells produce glucagon and delta cells produce somatostatin
120
What strains of rats are prone to hyperbilirubinemia? (can pick one or more options!)
A. GUNN rat with mutation in UGT1A1 (UDP-glucuronosyltransferase 1A1)
B. Long Evans Cinnamon rat (LEC) with deletion in ATP7b (copper transporting ATPase)
C. Nude rat athymic with *Foxn1rnu*
D. Zucker Fatty rat with hyperlipidemia *Leprfa*
A and B GUNN rats and Long Evans Cinnamon (remember cinnamon fur looks kinda yellow), both the enzymes mentioned here are in the hepatocytes and help with bile acid metabolism
Try to reason out that nude rats which are athymic have T cell deficient so are immunocompromised, not liver rat strain
Zucker Fatty rat is obesity model
121
Do rats have tonsils or gallbladders?
Yes or No
NO! no tonsils and no gallbladders!
122
Which maintains their thymus throughout life, mice or rats?
MICE
rats thymus involutes with age, commonly have ultimobranchial cysts
hemosiderin can accumulate and in spleen
123
If you see many mast cells in rat connective tissue this is likely a lesion?
T or F
FALSE, rats have increased mast cells in connective tissue compared to other species, this also means some CT tumors can have infiltrating mast cells and NOT be inflammation
124
Polyarteritis nodosa in Sprague Dawley rats can affect which organs (choose all correct)?
A. mesentery
B. pancreas
C. spermatic cord
D. tongue
E. brain
F. lungs
G. aorta
A. mesentery B. pancreas C. spermatic cord D. tongue
affects MUSCULAR arteries
NO reports of it in brain, lungs, or aorta
126
All are correct about spontaneous progressive cardiomyopathy in rats EXCEPT?
A. Young rats
B. Hypertensive rats
C. Males more than females
D. Idiopathic
A. young rats is WRONG, spontaneous progressive cardiomyopathy happens in aged rats over 1 year and is progressive, myofiber degeneration \>necrosis \>fibroplasia/fibrosis \> mild chronic inflammation/mineral
127
Myocardial mineralization in rats which is age-related and secondary to myocardial injury would be considered?
A. metastatic mineralization
B. dystrophic mineralization
B dystrophic mineralization! this is the most common reason for incidental epicardial and myocardial mineralization in both rats and mice, common in many strains
an example of metastatic mineralization would be secondary to renal disease (renal secondary hyperparathyroidism)
128
Which strain of rats is predisposed to Large granular cell (leukocyte) leukemia?
Fisher 344 (F344) in fact large granular cell leukemia is also called Fisher rat leukemia
129
Large granular leukocyte leukemia can cause all of the following clinical pathologic abnormalities EXCEPT?
A. thrombocytopenia
B. Anemia
C. Leukemia
D. Azurophilic granules in mononuclear cells
E. Polycythemia
LGCL causes anemia so it does not cause polycythemia (increased RBC) it tends to be space occupying in spleen and liver so causes destruction of RBC
all others are features of large granular cell leukemia in Fisher F344 rats
130
Large granular cell leukemia in Fisher rats have what immunophenotype?
T-cell, B-cell, or neither
NEITHER, potentially arise from NK cells as they have natural killer cell activity
granular - think about the mononuclear cells with azurophilic granules and think of cool NK cells
131
Spontaneous lymphoma is more common in mice or rats?
MICE! but rats also get lymphoma
so in rats, fewer types of lymphoma were mentioned: follicular cell lymphoma (low mitoses, in lymphoid organs), lymphoblastic lymphoma (intermediate, multiple organs, secondary leukemia), immunoblastic lymphoma (int to high, invasive sarcoma pattern)
132
In rats it is difficult to histologically distinguish lymphoma and mycoplasmosis
True or False?
TRUE
many lymphomas in tox studies in rats were reviewed and found to have inflammatory lesions associated with Mycoplasma pulmonis
133
What is the lesion and what is the strain?
BALB/c; no corpus collossum.
134
Tissue from a mouse. Name the condition and affected strain.
Alopecia areata, C3H mice get this, "Swarm of bees" around the hair bulb.
135
How does Streptococcus pneumoniae in guinea pigs differ grossly from that of Bordetella bronchiseptica?
Marked pleuropnemonia in Strep
136
Guinea pig adenovirus causes what lesion in the lung grossly?
bilateral consilidation of the lung lobes
137
138
Rhabdomyomatosis in guinea pigs occurs as a result of deposition of cardiac \_\_\_\_\_\_\_.
glycogen; vacuolated myofibers
139
What Cryptosporidium is found in guinea pigs?
Cryptosporidium wrairi; causes catarrahl enteritis and weight loss in young animals
140
Tissue from a guinea pig. 2 differentials?
Cavian leukemia and Strep zoo
141
L-gulonolactone oxidase is responsible for converting glucose to what?
ascorbic acid, lacking in primates and guinea pigs
142
What is the role of ascorbic acid in collagen synthesis?
it is the cofactor for lysl and proline hydroxylases which help form collagen, also responsible for cross-linkng collagen.
143
Trixacarus caviae is the burrowing mite of what species?
guinea pigs; the sarcoptic mange of guinea pigs
144
Guinea pig. Etiology?
Chlamydia caviae. Conjunctivitis.
145
Torticollis in guinea pigs is usually the result of infection with what? What other tissues are affected?
Bordetella bronchiseptica; lungs and uterus (endometritis)
146
Guinea pigs get this type of ovarian cyst most commonly.
Cystic rete ovarii (like dogs and cats)
147
Klossiella cobiyae are found in Guinea pigs. In what tissue and cell type do they occur?
Renal tubular epithelial cells in the kidney.
148
What allele in the parent is responsible for producing the lethal white syndrome in guinea pigs?
roan allele
149
Where does the esophagus enter the stomach of a hamster?
At the junction of the glandular and nonglandular stomach
150
The most common neoplasm of hamsters is ________ and is caused by \_\_\_\_\_\_\_. What is another lesion it can cause? Which lesions contains live virus?
trichoepithelioma; hamster polyomavirus-1 (HaPyV-1); lymphoma. The trichoepitheliomas contain live virus and the hematolymhoid masses don't contain liver virus, only fragments. Expression markers for lymphoma will vary with the organ affected!!
151
T-cell epitheliotropic lymphoma in hamsters occurs as a spontaneous/induced neoplasm.
spontaneous. Not virus-induced.
152
Demodectic mange in hamsters is caused by :
Demodex aurati or creti
153
A common cause of wet tail in hamsters is _______ which causes proliferative ileitis.
Lawsonia intracellulare
154
Which rodent is an excellent model of C. difficile?
Syrian hamsters
155
Gastritis asscoiated carcinoma in hamsters is associated with what bacteria?
Helicobacter spp.; antrum of stomach
156
This organism is a commensal bacteria in the crypts of hamsters.
Spirocerca muris
157
Tissue from a hamster. Disease and etiology. Where do you find the organisms histologically?
Tyzzer's disease, C. piliforme. MF to Coalescing necrotizing hepatitis. In periphery of necrotic region, intracellularly. Stacks. In gerbils, see the trifecta (intestine, heart, liver).
158
Lymphjocytic chriomeningitis virus is found in what two types of rodens?
mice and hamsters; ZOONOTIC. not found in rats
159
Spontaneous hemorrhagic necrrosis in hamsters has this characteristic gross feature.
Streak along the spinal cord; affects fetuses. They are cannibalized.
160
Thrombosis of the right aurciel in hamsters leads to right sided heart failure and what gross feature?
Ascites/subcutaneous edema "jelly hamster". This condition can also occur in systemic amyloidosis in hamsters.
161
What are gerbils used for in research?
Stroke research. Incomplete Circle of Willis
162
The fat sand rat is an intermediate host for what?
Leishmania tropica
163
What is a good model for Type II diabetes?
fat sand rat
164
What causes the red appearance of "red nose" in gerbils?
porphyrin
165
Tail slip in gerbils is the result of what?
Improper restraint; picking up at the end of the tail
166
Seizures in gerbils is the result of what two things?
inheritance and stress; no histo changes
167
Head tilt in gerbils is the result of:
aural cholesteatoma; masses of concentric layered keratinized epithelium
168
Tissue from a gerbil. Etiology?
Rodentolepis nana.
169
Gerbils are susceptible to what toxicity?
lead; lead inclusions in renal tubules
170
Tissue from a rat. Morph.
Endometrial stromal polyp. Usually unilateral and bloody.
171
Epicardial mineralization is common in what strains of mice?
C3H, DBA, BALB/c
172
Associated clin path finding?
proteinuria. Loss of antithrombin-3 predisposes.
173
Differentials for interstitial pneumonia in a mouse?
Pneumocystis murina in immunodeficient mice, Acidophilic macrophage pneumonia, pulmonary alveolar lipoproteinosis (phospholipidosis). Viral: Pneumonia virus of mice - immunodeficient mice only (paramyxovirus), Sendai virus (also a paramyxovirus), mouse norovirus in immunodeficient mice.
174
What are the crystals of acidiphilic macrophage pneumonia composed of?
Ym1 and Ym2 chitinase, containing iron, alpha-1 antitrypsin, immunoglobulin, and breakdown products of granulocytes
175
A strain mice have which activated oncogene?
kRAS
176
The most numerous cicrulating leukocyte in mice is:
the lymphocyte
177
The thymus in mice is different from other species in what way? What other lymphoid organ is missing in mice?
it doesn't involute; they don't have tonsils.
178
Lymphoma in mice are the result of what virus?
Maloney murine leukemia retrovirus; all wild and lab musculis spp.
179
Tissue from a mouse. Morph?
Lymphoma. Even nude mice get it - they still have lymphocytes but they don't work very well.
180
Mouse lymphomas are all of what cell lineage? What organ do they all arise from?
B cell;spleen
181
What strain of mouse gets salivary gland myoepithelialomas? What gender is over-represented? What is an associated finding?
BALB/c; older females; myeloid hyperplasia of bone marrow - unknown cause
182
What are the histo features of salivary gland myoepitheliomas in mice?
cystic with lots of spindle cells with a high nuclear:cytoplasmic ratio arranged in bundles.
183
Megaesophagus is common in what mouse strain?
Swiss ICRC mice; dilation on both sides of the diaphragm, more length of smooth muscle and aplasia of the myenteric plexus. Mucosa is markedly hyperplasia. Get esophageal papillomas more commonly with carcinogens.
184
What are common causes of diarrhea in mouse pups?
LIVIM (enterotropic mouse hepatitis virus i.e. coronavirus); EDIM (rotavirus); norovirus in immunodeficient mice; Salmonella; Clostridium piliforme
185
Mouse pup. Etiology?
Rotavirus - curdled milk. Typica rotaviral histo lesions prevent normal digestion and absorption of milk. Less than 14 days.
186
Tissue froma mouse pup. Etiologies?
Greasy mouse = reovirus type 3 is most common. Steatorrhea. Also rotavirus in young mice. Can also get necrosis in multiple organs, encepahlitis, hepatitis and myocarditis with reovirus.
187
Tissue from a mouse. Give 3 differential etiologies.
Myobia musculi, Myocoptes musculinis, Radfordia. Mites of mice - an appear on other species as well.
188
Tissue from a mouse. Potential sequala?
Polyplax serrata louse (common louse of mice) transmit the blood parasite Eperythrozoon coccoides. .
189
Tissue from a mouse. Name the condition and predisposing causes.
Clown mouse syndrome (any strain can get it). Previous infection with mouse hepatitis virus. Alopecia and hyperkeratotis. Can also occur with severe systemic disease of any kind. Hair regrowth occur first around the head, then posteriorly. So bald in back.
190
A subcuticular mass on the tail of an FVB mouse is most likely what? what is another common site
a neural crest tumor; pinnae
191
Which mouse strain is resistant to mouse pox ?
B6 mice
192
Tissue from a guinea pig.
Streptococcus pneumoniae --\> septicemia. (Strep zoo is "lumps", suppurative lymphadenitis)
193
Tissue from a ferret. 3 causes.
Splenic lymphoma. EMH. Infarction.
194
