AALAS Laboratory Animal Technician
Comprehensive Practice Examination
Laboratory Animal Health and Diseases
Questions And Correct Answers (Verified
Answers) Plus Rationales 2026 Q&A |
Instant Download Pdf
1. Which causative agent is responsible for Tyzzer’s disease in
laboratory rodents?
A. Corynebacterium kutscheri
B. Clostridium piliforme
C. Mycoplasma pulmonis
D. Helicobacter hepaticus
Answer: B
Rationale: Tyzzer’s disease is caused by Clostridium piliforme, an
obligate intracellular, spore-forming bacterium. It primarily affects the
gastrointestinal tract and liver of rodents, leading to diarrhea,
dehydration, and high mortality, especially in young or
immunocompromised animals.
2. Which viral pathogen in mice causes severe diarrhea, high
mortality in suckling mice, and characteristic syncytia formation in
the intestinal epithelium?
A. Mouse Hepatitis Virus
B. Epizootic Diarrhea of Infant Mice virus
,C. Sendai Virus
D. Murine Norovirus
Answer: B
Rationale: Epizootic Diarrhea of Infant Mice (EDIM) is caused by a
rotavirus that targets enterocytes of the small intestine in suckling
mice, causing watery diarrhea, stunt in growth, and syncytia
formation. Older mice usually experience subclinical infection.
3. What clinical condition in guinea pigs is characterized by
hypovertebral calcification, swollen joints, cutaneous hemorrhages,
and delayed wound healing due to a metabolic deficiency?
A. Pregnancy toxemia
B. Scurvy
C. Ulcerative pododermatitis
D. Metastatic calcification
Answer: B
Rationale: Guinea pigs lack the enzyme L-gulonolactone oxidase
required to synthesize Vitamin C (ascorbic acid). A deficiency in
dietary Vitamin C leads to scurvy, manifested by impaired collagen
synthesis, joint hemorrhage, and subcutaneous bleeding.
4. Which organism is the etiology of ringworm in laboratory rabbits
and rodents?
A. Pasteurella multocida
B. Trichophyton mentagrophytes
C. Bordetella bronchiseptica
,D. Streptobacillus moniliformis
Answer: B
Rationale: Dermatophytosis (ringworm) in rodents and rabbits is most
frequently caused by Trichophyton mentagrophytes, a zoonotic fungal
pathogen causing patchy alopecia, crusting, and scaling of the skin.
5. Which pathogen is responsible for "Snuffles" in European rabbits
(Oryctolagus cuniculus)?
A. Bordetella bronchiseptica
B. Pasteurella multocida
C. Pseudomonas aeruginosa
D. Mycoplasma pulmonis
Answer: B
Rationale: Pasteurella multocida is the primary causative organism of
snuffles in rabbits, leading to mucopurulent nasal discharge, sneezing,
conjunctivitis, otitis media, and pneumonia.
6. What is the pathognomonic clinical sign of Mycoplasma pulmonis
infection in rats?
A. Chromodacryorrhea and head tilt
B. Watery diarrhea and rectal prolapse
C. Severe hindlimb paralysis
D. Hematuria and polyuria
Answer: A
Rationale: Mycoplasma pulmonis causes Murine Respiratory
Mycoplasmosis (MRM), presenting with upper and lower respiratory
, signs, porphyrin staining around the eyes and nares
(chromodacryorrhea), and inner ear infection causing head tilt
(torticollis).
7. Which virus is a major cause of interstitial pneumonia, rhinitis, and
high mortality in susceptible mouse colonies?
A. Sendai Virus
B. Mouse Cytomegalovirus
C. Lymphocytic Choriomeningitis Virus
D. Mouse Parvovirus
Answer: A
Rationale: Sendai virus is a paramyxovirus that causes acute, highly
contagious respiratory disease in mice and rats, characterized by
necrosis of the respiratory epithelium and interstitial pneumonia.
8. What condition in non-human primates is caused by
Mycobacterium tuberculosis or Mycobacterium bovis and requires
routine tuberculin skin testing for detection?
A. Measles
B. Tuberculosis
C. Shigellosis
D. Candidiasis
Answer: B
Rationale: Tuberculosis in non-human primates is a severe, zoonotic,
chronic granulomatous disease primarily caused by M. tuberculosis or
M. bovis. Intradermal tuberculin skin testing in the eyelid is a
standard surveillance procedure.
Comprehensive Practice Examination
Laboratory Animal Health and Diseases
Questions And Correct Answers (Verified
Answers) Plus Rationales 2026 Q&A |
Instant Download Pdf
1. Which causative agent is responsible for Tyzzer’s disease in
laboratory rodents?
A. Corynebacterium kutscheri
B. Clostridium piliforme
C. Mycoplasma pulmonis
D. Helicobacter hepaticus
Answer: B
Rationale: Tyzzer’s disease is caused by Clostridium piliforme, an
obligate intracellular, spore-forming bacterium. It primarily affects the
gastrointestinal tract and liver of rodents, leading to diarrhea,
dehydration, and high mortality, especially in young or
immunocompromised animals.
2. Which viral pathogen in mice causes severe diarrhea, high
mortality in suckling mice, and characteristic syncytia formation in
the intestinal epithelium?
A. Mouse Hepatitis Virus
B. Epizootic Diarrhea of Infant Mice virus
,C. Sendai Virus
D. Murine Norovirus
Answer: B
Rationale: Epizootic Diarrhea of Infant Mice (EDIM) is caused by a
rotavirus that targets enterocytes of the small intestine in suckling
mice, causing watery diarrhea, stunt in growth, and syncytia
formation. Older mice usually experience subclinical infection.
3. What clinical condition in guinea pigs is characterized by
hypovertebral calcification, swollen joints, cutaneous hemorrhages,
and delayed wound healing due to a metabolic deficiency?
A. Pregnancy toxemia
B. Scurvy
C. Ulcerative pododermatitis
D. Metastatic calcification
Answer: B
Rationale: Guinea pigs lack the enzyme L-gulonolactone oxidase
required to synthesize Vitamin C (ascorbic acid). A deficiency in
dietary Vitamin C leads to scurvy, manifested by impaired collagen
synthesis, joint hemorrhage, and subcutaneous bleeding.
4. Which organism is the etiology of ringworm in laboratory rabbits
and rodents?
A. Pasteurella multocida
B. Trichophyton mentagrophytes
C. Bordetella bronchiseptica
,D. Streptobacillus moniliformis
Answer: B
Rationale: Dermatophytosis (ringworm) in rodents and rabbits is most
frequently caused by Trichophyton mentagrophytes, a zoonotic fungal
pathogen causing patchy alopecia, crusting, and scaling of the skin.
5. Which pathogen is responsible for "Snuffles" in European rabbits
(Oryctolagus cuniculus)?
A. Bordetella bronchiseptica
B. Pasteurella multocida
C. Pseudomonas aeruginosa
D. Mycoplasma pulmonis
Answer: B
Rationale: Pasteurella multocida is the primary causative organism of
snuffles in rabbits, leading to mucopurulent nasal discharge, sneezing,
conjunctivitis, otitis media, and pneumonia.
6. What is the pathognomonic clinical sign of Mycoplasma pulmonis
infection in rats?
A. Chromodacryorrhea and head tilt
B. Watery diarrhea and rectal prolapse
C. Severe hindlimb paralysis
D. Hematuria and polyuria
Answer: A
Rationale: Mycoplasma pulmonis causes Murine Respiratory
Mycoplasmosis (MRM), presenting with upper and lower respiratory
, signs, porphyrin staining around the eyes and nares
(chromodacryorrhea), and inner ear infection causing head tilt
(torticollis).
7. Which virus is a major cause of interstitial pneumonia, rhinitis, and
high mortality in susceptible mouse colonies?
A. Sendai Virus
B. Mouse Cytomegalovirus
C. Lymphocytic Choriomeningitis Virus
D. Mouse Parvovirus
Answer: A
Rationale: Sendai virus is a paramyxovirus that causes acute, highly
contagious respiratory disease in mice and rats, characterized by
necrosis of the respiratory epithelium and interstitial pneumonia.
8. What condition in non-human primates is caused by
Mycobacterium tuberculosis or Mycobacterium bovis and requires
routine tuberculin skin testing for detection?
A. Measles
B. Tuberculosis
C. Shigellosis
D. Candidiasis
Answer: B
Rationale: Tuberculosis in non-human primates is a severe, zoonotic,
chronic granulomatous disease primarily caused by M. tuberculosis or
M. bovis. Intradermal tuberculin skin testing in the eyelid is a
standard surveillance procedure.
