Syrian Hamsters BB/P&B Flashcards Preview

Hamsters, GPs, other rodents > Syrian Hamsters BB/P&B > Flashcards

Flashcards in Syrian Hamsters BB/P&B Deck (131)
Loading flashcards...
1
Q

What is the genus and species of the:

Syrian Hamster

Chinese Hamster

Armenian Hamster

European Hamster

Djungarian Hamster

A

Mesocricetus auratus

Cricetulus griseus

Cricetulus migratorius

Cricetus cricetus

Phodopus cambelli (Russian dwarf) and Phodopus sungorus (Siberian dwarf).

2
Q

To which taxonomic family do hamsters belong?

What are some distinguishing characteristics of this family?

A

Cricetidae - large cheek pouches, short tails, and excess loose skin. They have incisors that grow continuously and cuspidate molars that do not continue to grow.

3
Q

T/F The Syrian hamster is diurnal.

A

False. They are nocturnal.

4
Q

What is the life span and breeding life span of the Syrian hamster?

A

Ave. life span = 2 years (max. = 3 years) - lifespan may be shorter in female than male depending on strain and source

Breeding life = 1 year (6-8 weeks of age to 15 months of age).

5
Q

What is a commonly used strain to study CHF and is used extensively in cardiomyopathy research?

Name two additional cardiomyopathic strains

A

BIO 14.6

BIO 82.62, BIO-TO-2, BIO 53.58 (idiopathic dilative cardiomyopathy), UMX (model of severe childhood autosomal recessive muscular dystrophy).

6
Q

T/F Hamsters have relatively few spontaneous diseases, but are susceptible to many experimentally induced diseases.

A

T

7
Q

T/F The Syrian hamster is resistant to tumor induction by viruses of other species (e.g. SV40).

A

F - The hamster is susceptible to tumor induction by viruses of other species, such as polyomavirus of mice, SV40, and human adenovirus

8
Q

T/F Histoplasmosis has been studied extensively in hamsters as they are sensitive to small inocula and are useful for diagnostic purposes.

A

True - they are susceptible to most deep fungal infections

9
Q

Conchoid Schaumann bodies are produced during __________ and __________ infections.

A

mycobacterial and leishmanial

10
Q

Hamsters infected with ___________are used as models of local infection of the respiratory tract.

A

Mycoplasma pneumoniae

11
Q

Name two other infectious diseases to which Syrian hamsters are susceptible.

A

tuberculosis, leprosy, atypical mycobacterial infections, leptospirosis, and various viral, protozoal and helminthic infections.

12
Q

Hamsters are useful models of prion diseases because of their susceptibility to agents such as____________________.

A

scrapie, transmissible mink encepholopathy (TME), CJD, and Gerstmann-Staussler syndrome (GSS)

13
Q

List the unique attributes of the hamster cheek pouch and name two types of studies for which this anatomic site is useful.

A

They do not contain glands, they are rich in mast cells, easily everted with blood flow intact, lack an intact lymphatic drainage pathway (“immunologically privileged”), decreased density of Langerhans cells.

Used for microvascular studies of inflammation, tumor growth, vascular smooth muscle function

Transplantation of foreign tissue without immunologic rejection - this research use has largely been replaced by the nude mouse

Considered the best carcinogenesis model for evaluation of human oral cancer development.

14
Q

T/F Related to the short gestation period of the Syrian hamster, the ontogeny of the thymic system and associated cellular immunity is delayed compared to other rodents.

A

True

15
Q

Which class of immunoglobulin has not been defined in the hamster?

A

IgD; also, some inbred strains are deficient in the sixth component of complement and another isotype of IgG (IgG3) has been described in others.

16
Q

At what temperature will hamsters generally hibernate?

A

5 C +/- 2

17
Q

T/F A hamster does not fatten prior to hibernation, and will starve if it does not wake periodically to eat.

A

T

18
Q

Hibernation is associated with desaturation of white or brown adipose tissue? Select one.

A

White

19
Q

Syrian and Chinese hamsters are among the most radioresistant or radiosensitive mammals known.

A

Radioresistant

20
Q

What type of dental studies are Syrian hamsters used for?

A

Study of etiological factors for caries development - they develop caries in response to CHO in diets

21
Q

The flank glands of Syrian hamsters are ____________glands that produce secretions in response to ________________.

A

Sebaceous

Androgens

22
Q

Are flank glands more prominent in the male or female hamsters?

A

Male

23
Q

True or False: Antibodies to the MAdV-2 (K87) strain of mouse adenovirus are commonly present in hamsters from commercial suppliers in the US.

A

True

24
Q

True or False: Adenovirus commonly causes clinical signs in hamsters.

A

False - infected hamsters are asymptomatic

25
Q

Name the pathologic hallmark of adenoviral infection in the hamster.

A

Large, amphophilic intranuclear inclusions in enterocytes lining villi & goblet cells of jejunum & ileum

26
Q

Malformed or missing incisors in suckling and weanling hamster pups is indicative of what?

A

Toolan H-1 virus - a rat parvovirus

Recent data suggests that Hamster Parvovirus is distinct from rat parvovirus, although very closely related

27
Q

True or False: Hamster parvovirus is over 98% homologous to MPV-3.

A

True.

Infection in hamsters occurs through interspecies transmission from mice, which are the natural rodent host for this virus.

28
Q

Name the etiology of transmissible lymphoma in hamsters.

A

Hamster polyoma virus (HaPV)

Transmissible lymphoma occurs in epizootics among young hamsters

29
Q

Keratinizing skin tumors of hair follicle origin are caused by what virus?

A

HaPV - not to be called hamster papillomavirus even though the polyoma virus can cause papilloma-like skin lesions

30
Q

HaPV is spread by environmental contamination with what excrement?

A

Urine

31
Q

True or False: HaPV is oncogenic, but tumor formation is a side effect of infection and not critical to the virus life cycle.

A

True

32
Q

Do lymphomas caused by HaPV have detectable infectious virus?

A

No - this is because HaPV can infect cells lytically with virus replication or transform cells without virus replication.

33
Q

True or False: HaPV epitheliomas have virus replication in keratinizing epithelium, similar to the behavior of papillomaviruses.

A

True - HaPV epitheliomas do shed infectious virus, unlike HaPV lymphomas

34
Q

Explain what may happen when HaPV is introduced into a naïve population of breeding hamsters.

A

Epizootic of lymphoma with attack rates as high as 80% among young hamsters within 4-30 wk postexposure - this is a diagnostic phenomenon

Infected hamsters may also have epitheliomas, usually around the face and feet.

Once enzootic, incidence of lymphoma declines to much lower levels.

35
Q

Hamsters with lymphoma appear thin and often have palpable masses in their abdomens. Where do lymphomas usually arise?

A

In the mesentery, without involvement of the spleen.

Can also occur in axillary & cervical lymphadenopathy

Infiltration of liver, kidney, thymus, other organs may occur.

36
Q

Why is epizootic HaPV unmistakable?

A

Lymphoid tumors are otherwise rare in hamsters (especially YOUNG hamsters) and when they occur it is in aged hamsters.

37
Q

True or False: Trichoepitheliomas have been described in hamsters due to causes other than HaPV.

A

False

38
Q

Describe how to effectively eliminate HaPV.

A

Total depopulation and thorough decontamination of the premises.

The virus is resistant to environmental decontamination.

39
Q

What is the proposed function of flank glands in Syrian hamsters?

A

They appear to play a role in the conversion of testosterone to dihydrotestosterone

Used in territorial marking

40
Q

Flank glands are (resistant/sensitive) to locally applied carcinogens but are (resistant/sensitive) to transformation associated with the administration of estrogens and androgens.

A

Resistant

Sensitive

41
Q

T/F Spontaneous bronchiogenic and pulmonary tumors are relatively common in the Syrian hamster.

A

F: Spontaneous bronchiogenic and pulmonary tumors are rare

Syrian hamsters are good models for chemical carcinogenesis of the respiratory tract.

42
Q

What two factors make the Syrian hamster a good model for the effects of long term smoke inhalation?

A

They are resistant to pulmonary infection and are able to decompose nicotine.

43
Q

What is unique about the stomach of the Syrian hamster?

A

The esophagus enters between a forestomach and a glandular stomach compartment

The forestomach is similar to that of ruminants in that it has an elevated pH and microorganisms contribute to digestion through fermentation.

44
Q

T/F Spontaneous tumors of the GI tract are relatively common in the Syrian hamster.

A

True

45
Q

Helicobacter aurati has been associated with what disease condition in the Syrian hamster?

A

Gastritis and intestinal metaplasia

46
Q

T/F The hamster is similar to mice and rats in that the pancreatic ducts join the common bile duct prior to entering the duodenum.

A

T

47
Q

Why is the hamster a good model of pancreatic carcinogenesis?

A

It is the only animal model in which pancreatic tumors can be induced that are comparable to human tumors, both morphologically and clinically.

48
Q

The administration of estrogen to male hamsters causes ______________.

A

Renal tumors

This makes Syrian hamsters one the best models of renal cancer

49
Q

T/F The hamster is reported to be the first model in which the equivalent of Addisonian adrenal necrosis could be studied.

A

T

50
Q

The adrenal glands are larger in the male or female hamsters?

A

Male - their zona reticularis is upto 3X larger than females

51
Q

T/F: Sexual dimorphism is seen in the harderian gland of all species of hamsters, with females secreting 100-1000 times more porphyrin than males.

A

F: This has only been reported in the Syrian hamster.

52
Q

What unique feature of the hamster oocyte has made it a useful tool in the assessment of human fertility?

A

The hamster oocyte is penetrable by human spermatozoa, making it useful to aid in the assessment of human fertility using the zona-free hamster oocyte assay. It can also be used to investigate treatments for human male infertility.

53
Q

Syrian hamsters are an excellent model for studying teratogenic agents because of their short life cycle (18-24 mths).

What day of gestation is the optimal time for teratogenic effects?

A

The 8th day - when hourly development of the fetal pups can be observed

54
Q

At what age in M. auratus do the following occur:

Eruption of incisors

Ears open

Hair growth observed

Eyes open

A

Incisors are present at birth

Ears open at day 5

Hair growth observed at day 9

Eyes open at day 15

55
Q

Name three ways male and female hamsters distinguished?

A

Adult females are larger than adult males

Shorter anogenital distance in females

Presence of mammae in female

Observation of posterior scrotum in male.

56
Q

T/F Serum chemistry parameters may deffer between sexes and strains of hamsters.

A

True - serum chemistries may differ b/w the sexes, but specifics are not listed in BB

57
Q

What is the diploid chromosome number of M. auratus?

A

2N = 44

58
Q

What is the food consumption of M. auratus during growth and development?

A

5.5-7 g/day

59
Q

What is the fluid requirement for hamsters?

A

30ml/animal/day

60
Q

How do the nutritional requirements of the Syrian hamster differ from mice and rats with respect to protein source in the diet?

A

For hamsters, unlike other rodents, soybean meal offers better nutritional efficiency than fish meal.

61
Q

How does the stomach differ in hamsters compared to other rodents?

A

The hamster has a forestomach in which the first stage of digestion is a fermentation process that affects the utilization of nutrients.

62
Q

Syrian hamsters require sources of many of the ________vitamins and also need a source of nonnutritive bulk.

A

B vitamins

63
Q

Vitamin__________ has been reported as essential for preventing myocytolysis in cardiomyopathic hamster strains.

A

Vitamin E

64
Q

T/F Hamsters changed from a diet of rodent chow to semipurified feed are susceptible to colocolic intussusception within 7-10 days.

A

True

65
Q

Due to the hamster’s broad muzzle, how do feeding recommendations for this species differ from those for other rodents?

A

Feed pellets must be able to fall through the slots of the hopper to the floor or food may be placed directly on the floor of the cage.

66
Q

Hamsters are more sensitive to the metabolic effects of _____________ and less responsive to ____________ compared to other laboratory rodents.

A

Corticosteroids

Histamine

67
Q

Hamsters are very resistant to which opioid?

A

Morphine - generally has no sedative or hypnotic effects in this species

68
Q

Male Syrian hamsters are sexually mature when they reach a weight of ________.

A

90 grams

69
Q

In female hamsters, estrus begins by 6-8 weeks of age, but it is recommended to withhold breeding until they reach _________grams in weight.

A

90-100

70
Q

How long is the estrous cycle in the Syrian hamster?

A

Four days

71
Q

Based on the presence of the postovulatory discharge, when is the optimum time to breed the female?

Describe how to manage the breeding animals.

A

The discharge marks the end of ovulation - usually day 2 of the cycle

Optimum timing for breeding is in the evening of the 3rd day after the postovulatory discharge.

Introduce the female to the male’s cage 2 hours after beginning of the dark cycle. Remove if fighting occurs or if there is no mating within 5 minutes.

72
Q

How does a female hamster indicate that she is receptive to mating?

A

She will assume a position of lordosis with hindlegs spread and tail erect

73
Q

What is the gestation period of the Syrian hamster?

A

15-18 days

74
Q

Infertile mating often results in ___________.

A

Pseudopregnancy

75
Q

A hamster that is pregnant will have a distinct gain in weight with abdominal distention by _________ days after mating.

A

10 days after mating

76
Q

T/F The most common time for parturition is on day 17 of gestation and parturition itself rarely lasts for more than an hour.

A

False

Parturition usually occurs on day 16 of gestation and usually lasts for >3 hours

77
Q

In order to decrease the likelihood of cannibalism by the dam, pups should be left undisturbed for the first _________days after birth.

A

7-10 days

78
Q

Weaning usually occurs at ___________days of age.

A

21-28 days

79
Q

Mature hamsters should be housed:

a) in pairs
b) in groups up to 4 animals
c) singly

A

c) singly - due to their tendency to fight

80
Q

_______________ in cedar and pine bedding may induce____________ and should therefore not be used.

A

Aromatic hydrocarbons

Nonspecific hepatic enzymes - cytochrome P450

81
Q

What photoperiod is recommended for adult hamsters?

A

12-14 hour light period

The longer 14 hour period is recommended for breeding

82
Q

T/F Females are more docile and easier to handle than males.

A

False: males are more docile than females

83
Q

What is the causative agent of proliferative enteritis?

Is this a common or uncommon disease of hamsters?

Describe levels of morbidity & mortality.

What age group is affected?

A

Lawsonia intracellularis

It is among the most commonly recognized disease of the Syrian hamster

It produces high morbidity and high mortality

Young animals - postweaning

84
Q

What gross lesions are associated with proliferative enteritis?

A

Segmental thickening & congestion of the ileum

Enlargement of the mesenteric lymph nodes

Peritonitis & adhesions.

85
Q

Lawsonia organisms can often be identified in the ____________ using ___________ stain.

A

Apical cytoplasm of crypt enterocytes

Warthin-Starry silver stain

86
Q

Lesions associated with proliferative enteritis develop in two stages. The first involves________________ and the second involves_______________.

A

Hyperplasia of the epithelium lining the crypts and villi

Granulomatous inflammation in the submucosa and muscularis

87
Q

Name three bacteria associated with pneumonia in hamsters.

A

Streptococcus pneumoniae, Pasteurella pneumotropica, Corynebacterium paulometabulum

88
Q

What is the etilogic agent of Tyzzer’s disease in hamsters?

What clinical signs are associated with Tyzzer’s disease in hamsters?

What age group is primarily affected?

What gross & histopathologic lesions are observed?

A

Clostridium piliforme

Roughened hair coat, diarrhea, & high mortality

Usually in animals of weaning age or immunosuppressed animals

Enterocolitis, multifocal necrotizing hepatitis & myocarditis w/ bundles of intracellular bacilli ID with silver stain

89
Q

Enteritis associated with what organism has been linked to inappropriate antibiotic administration, stress, and experimental administration?

What antibiotics are associated with enterocolitis in hamsters?

What is the typical presentation of antibiotic associated enterocolitis?

A

Clostridium difficile

Lincomycin, clindamycin, ampicillin, erythromycin, cephalosporins, gentamicin, penicillin

Profuse diarrhea with high mortality occurring 2-10 days following administration of antibiotics

90
Q

T/F: Hamster models of atherosclerosis placed on high-fat diets may be prone to develop enteric disease associated with toxigenic C. difficile.

A

True

91
Q

T/F: Salmonellosis is relatively common in hamsters.

What serotypes are Syrian hamsters susceptible to?

A

False - although Syrian hamsters are very susceptible to infection with Salmonella

S. typhimurium and S. enteritidis are the most frequent isolates

92
Q

What gross lesions are associated with salmonellosis in the hamster?

A

Multifocal hepatic necrosi & interstitial pneumonitis, but no enteritis

93
Q

Name five viral pathogens for which it is recommended to monitor hamsters colonies.

A
  1. LCMV
  2. PVM
  3. Reo 3
  4. Sendai virus
  5. Rodent protoparvovirus
94
Q

Name two types of disease caused by LCMV in hamsters.

A
  1. Chronic, progressive fatal characterized by wasting (congenital or newborn infection)
  2. Subclinical infection (adult infection)
95
Q

How is LCMV transmitted in hamsters?

A
  1. Transplantable tumors - SIGNIFICANT source of virus in the laboratory
  2. Direct contact
  3. Fomites
  4. Aerosols (attributable to excretion of high viral titers in urine) - cage to cage transmission via aerosols DOES NOT appear to occur commonly
  5. Vertical transmission
96
Q

What histopathologic lesions are associated with LCMV?

How is LCMV diagnosed in hamsters?

A

lymphocytic infiltration of the liver, lung, pancreas, kidney, spleen, meninges, and brain

Chronic glomerulonephropathy and vasculitis - immune complex dz

Serology is used to confirm the diagnosis: animals usually remain seropositive for a long time

Some infected hamsters have anti-complement activity that complicates interpretation of the complement fixation test

97
Q

T/F: LCMV is not transmissible from hamsters to humans.

A

False: LCMV infected hamsters are recognized to be a major source of zoonotic infection in human patients

98
Q

Sendai Virus is a single stranded-stranded RNA or DNA virus in what family of viruses?

A

RNA virus in the Paramyxoviridae family

99
Q

What is the most common clinical course of Sendai virus in the hamster?

What lesions may be seen in affected animals?

A

Usually subclinical, but may lead to mortality in newborn Syrian and Chinese hamsters

Focal to segmental rhinitis progressing to necrotizing tracheitis and multifocal bronchoalveolitis

100
Q

What is the best way to prevent Sendai virus infection in hamsters?

A

Exclusion

101
Q

To which group of viruses does type C virus belong?

What is it’s signficance in hamsters?

A

Oncovirus - it is an endogenous retrovirus

It is expressed in tissues & cells as C-type particles without evidence of oncogenicity, but other Oncoviruses are known leukemic agents (FeLV, BoLeukV) so it’s presence may complicate oncology studies

102
Q

T/F: Protozoa are found in large numbers in fecal smears of hamsters, but their role in enteric disease is not clearly defined.

A

True

103
Q

Which oxyurids can infect hamsters?

What are their significance in hamsters?

A

Infection with S. obvelata (mouse pinworm) is most common

Syphacia criceti & S. mesocriceti are natural hamster pinworms

S. muris (rat pinworm) can infect hamsters

Aspiculuris tetraptera infects Siberian dwarf hamsters

Significance: may affect GI studies & cross-species transmission is a concern

104
Q

What is the most important internal parasite found in hamsters?

A

Rodentolepis nana

105
Q

What is the host range of Rodentolepis nana?

What is significant about the life cycle of R. nana?

A

Mice, rats, NHPs, & humans

It has both a direct and indirect life cycle

106
Q

What clinical signs are associated with H.nana in the hamster?

A

Usually none, but may be associated with intestinal impaction depending on the number of parasites.

107
Q

What are the two most common causes of acariasis in the hamster?

When are these infestations associated with skin lesions?

A

Demodex criceti and Demodex aurati

When there identifiable predisposing factors, such as experimental manipulations and/or advanced age

108
Q

What other mites reportedly infect hamsters?

A
  • Notoedres spp. *
  • Ornithonyssus bacoti* (tropical rat mite)
  • Spleorodens clethrionomys* (a nasal mite)
109
Q

What is the most frequently reported malignant neoplasia in the Syrian hamster?

A

Lymphosarcoma

110
Q

In which sex is the reported incidence of malignant melanoma higher?

A

Males (10:1)

111
Q

What noninfectious disease is a principle cause of death in hamsters in long term studies?

Which sex is more commonly affected by this condition?

A

Amyloidosis

Females

112
Q

Name two components of amyloid.

A

Amyloid A (AA) - derived from amyloid fibrils

AmyloidP (AP), also known as hamster female protein (FP) - regulated by sex hormones

113
Q

Injection of what compound can experimentally induce amyloidosis in hamsters?

What are the typical lesions observed in amyloidosis?

What stains are used to verify amyloid?

A

Casein

Kidneys are pale & livers are swollen - kidney, liver & adrenal glands are most commonly affected

Congo red or thioflavin T

114
Q

Polycystic disease is common in hamsters and __________is the most frequently affected site.

What is the etiology of polycystic disease?

Where else might lesions be identified?

A

LIVER

Congenital

Epididymis, seminal vesicles, & pancreas

115
Q

T/F: There is a higher reported incidence of intraperitoneal cysts in European hamsters compared to Syrian hamsters.

A

True

116
Q

Antibiotic-associated enterocolitis is observed following administration of antibiotics that are selective for gram_______organisms.

A

POSITIVE

117
Q

Hamsters were inadvertently infected with what Leptospira species by inoculation with contaminated tissue?

A

Leptospira ballum

Hamsters are highly susceptible to experimental inoculation with a number of Leptospira species, but no natural infections have been reported.

118
Q

Are Syrian hamsters considered permissive or obligatory hibernators? How can hypernation induced?

Are Syrian hamsters capable of estuvation?

A

Permissive hibernators - induced by low temp, short days, solitude, nesting material, inadequate food stores

Yes - induced by high temperature, low water, and other factors that require a state of dormancy and reduced metabolic activity

119
Q

Administration of nitrosamides to hamsters is a model for?

A

pancreatic duct adenocarcinoma

120
Q

Administration of PGHAM-1 cell line to hamsters is a model for what?

A

metastatic pancreatic cancer

121
Q

Name 3 ways to induce diabetes mellitus in hamsters

A

adminstration of streptozocin

administration of alloxan

high-fat (15%) diet with modest cholesterol

122
Q

In what way does the hamster serve as a model of Alzheimer’s disease?

A

Hamsters develop amyloid-like deposits in their brains.

123
Q

What is the weaning age of hamsters?

age of maturity?

weight at maturity?

A

21 days

6-8 weeks

110-120 g

124
Q

What makes the hamster an excellen model for the evaluation of human oral cancer development?

A

Cheek pouches are immunologically privileged - they have a lower surface density fo Langerhans cells and no intact lymphatic drainage

125
Q

Administration of estrogen to male hamsters results in?

A

renal t umors

126
Q

Two things of note regarding hamster harderian glands:

A

1: female Syrian hamsters have up to a thousand times more porphyrin than males.
1. this sexual dimorphism is only seen in the syrian hamster

127
Q

Infection with HaPyV is associated with what two clinical syndromes?

A

HaPyV = hamster polyomavirus

  1. epizootic multicentric lymphoma involving the mesentery, intestines, liver, kidney, and thymus in infected juvenile hamsters
  2. trichoepitheliomas on the face, feet, neck, back, flanks, and abdomen in juvenile to adult hamsters
128
Q

What is unusual about HaPyV?

A

It has tropism for both undifferentiated keratinocytes and lympocytes.

129
Q

Hamster parvovirus is most homologous to what viral agent in mice?

A

MPV-3

130
Q

What is nephrotic syndrome, and what condition is it associated with in hamsters?

A

low ablumin, ascites, proteinuria

amyloidosis

131
Q

Demodex cricetuli infests which species of hamster?

A

Armenian