ICVA NAVLE Exam 1
Practice Test (2025)
NAVLE Exam Review
Exam for Veterinary Medicine
-
,Fifteen of a group of 200, 7 month old feedlot calves are lame. The calves arrived at the feedlot approximately
one month ago, and one week later, 40 of the animals developed pneumonia. These calves were treated with
oxytetracycline, and the pneumonia appeared to resolve. On physical examination, the affect calves have
swellings in the carpi, tarsi, and stifles with distension of associated tendon sheaths, and stiff gait. Two calves
are euthanized. Postmortem eamination shows fibrinous pleuritis and papillary muscle necrosis. Which of the
following organisms is the most likely cuase of these signs?
a) arcanobacterium (actinomyces) pyogenes
b) histophilus somni
c ) mannheimia hemolytica
d) pasteurella multocida
e) salmonella thyphimurium - CORRECT ANSWER -B) histophilus somni
Histophilus somni is a well known cause of systemic disease in feedlot cattle, including respiratory disease,
speticemia, and polyarthritis. In this case, the calves initially developed pneumonia, and now soe of them
show signs of lameness, joint swelling, and stiff gait, which are consistent with septic arthritis, and
polyarthritis that can occur after a histophilus somni infection
- additionally the post mortem finding of fibrinous pleuritis and papillary muscle necrosis also strongly
suggest histophilus soni as the causative agent.
-Known to cause arthritis, pleuritis, myocarditis, and septicemia in calves
What is hyperkalemic periodic paralysis in a horse - CORRECT ANSWER --a genetic disorder that affects
muscles causing episodes of muscle weakness or paralysis.
-It is autosomal dominant
What is the cause of hyperkalemic periodic paralysis - CORRECT ANSWER -THe disorder is caused by a
mutation in the sodium channel gene, leading to increased potassium levels in the blood. This affects the
electrical activity of muscle cells, causing the muscles to contract abnormally
What are symptoms of hyperkalemic periodic paralysis in horses - CORRECT ANSWER --muscle twitching
or trembling
,-weakness or partial paralysis especially in hindquarters
-episodes of muscle stiffness
-respiratory issues in severe cases
-horse remains alert
what are triggers of hyperkalemic periodic paralysis - CORRECT ANSWER --high potassium intake from
feed such as alfalfa, molasses or certain grains
-stress, exercise or fasting
how would you manage hyperkalemic periodic paralysis - CORRECT ANSWER --dietary modification like
feeding low potassium diets and aoiding alfala and monitor potassium intake
-medicate with acetazolamide and hydrochlorothiazide
-consistent exercise and minimize stress
A 3-year old Percheron mare is undergoing routine dental evaluation. Physical examination shows bilateral
prolapse of the nictitating membrane and muscle fasciculations of the neck, shoulders, and flank. During
examination, the mare's hindlimbs give way, and she leans back in a dog-sitting posture. Rectal temperature is
100.4 degrees F (38.0 degrees C), heart rate is 60 beats/min, and respiratory rate is 30 breaths/min.
Which of the following is the most likely diagnosis?
A) Equine degenerative myeloneuropathy
B) Equine motor neuron disease
C) Exertional rhabdomyolysis
D) Hyperkalemic periodic paralysis
E) Tetanus - CORRECT ANSWER -D) hyperkalemic periodic paralysis
HYPP leads to episodes of periodic muscle weakness or paralysis.
, -Prolapse of the nictitating membrane is characteristic of HYPP due to muscle weakness in the face
-Weakness and collapse suggest muscle paralysis or severe weakness, dog sitting posture strongly supports this
A 3-year old Percheron mare is undergoing routine dental evaluation. Physical examination shows bilateral
prolapse of the nictitating membrane and muscle fasciculations of the neck, shoulders, and flank. During
examination, the mare's hindlimbs give way, and she leans back in a dog-sitting posture. Rectal temperature is
100.4 degrees F (38.0 degrees C), heart rate is 60 beats/min, and respiratory rate is 30 breaths/min.
This is a case of HYPP, why would Equine Degenerative Myeloneuropathy be incorrect - CORRECT
ANSWER -EDM is a neurodegenerative disease that causes progresse ataxia ( incoordination) and weakness
in young horses, particularly those deficient in vitamin E.
Although it causes weakness, EDM is more associated with ataxia ( uncoordinated movement) rather than
acute muscle fasciculations or prolapse of the nictitating membrane. It is a chronic, progressive condition,
unlike the episodic nature of HYPP
A 3-year old Percheron mare is undergoing routine dental evaluation. Physical examination shows bilateral
prolapse of the nictitating membrane and muscle fasciculations of the neck, shoulders, and flank. During
examination, the mare's hindlimbs give way, and she leans back in a dog-sitting posture. Rectal temperature is
100.4 degrees F (38.0 degrees C), heart rate is 60 beats/min, and respiratory rate is 30 breaths/min.
This is a case of HYPP, why would Equine Motor Neuron Disease be incorrect - CORRECT ANSWER -
EMND is a neurodegeneratie disorder and is associated with vitamin E deficiency
-EMND causes muscle atrophy and weakness, primarily affecting posture and gait over time. However it does
not typically cause acute episodes of weakness with fasciculation and prolapse of the third eyelid like HYPP
does. EMND is also more chronic in its progression, not episodic.
A 3-year old Percheron mare is undergoing routine dental evaluation. Physical examination shows bilateral
prolapse of the nictitating membrane and muscle fasciculations of the neck, shoulders, and flank. During
examination, the mare's hindlimbs give way, and she leans back in a dog-sitting posture. Rectal temperature is
100.4 degrees F (38.0 degrees C), heart rate is 60 beats/min, and respiratory rate is 30 breaths/min.
Practice Test (2025)
NAVLE Exam Review
Exam for Veterinary Medicine
-
,Fifteen of a group of 200, 7 month old feedlot calves are lame. The calves arrived at the feedlot approximately
one month ago, and one week later, 40 of the animals developed pneumonia. These calves were treated with
oxytetracycline, and the pneumonia appeared to resolve. On physical examination, the affect calves have
swellings in the carpi, tarsi, and stifles with distension of associated tendon sheaths, and stiff gait. Two calves
are euthanized. Postmortem eamination shows fibrinous pleuritis and papillary muscle necrosis. Which of the
following organisms is the most likely cuase of these signs?
a) arcanobacterium (actinomyces) pyogenes
b) histophilus somni
c ) mannheimia hemolytica
d) pasteurella multocida
e) salmonella thyphimurium - CORRECT ANSWER -B) histophilus somni
Histophilus somni is a well known cause of systemic disease in feedlot cattle, including respiratory disease,
speticemia, and polyarthritis. In this case, the calves initially developed pneumonia, and now soe of them
show signs of lameness, joint swelling, and stiff gait, which are consistent with septic arthritis, and
polyarthritis that can occur after a histophilus somni infection
- additionally the post mortem finding of fibrinous pleuritis and papillary muscle necrosis also strongly
suggest histophilus soni as the causative agent.
-Known to cause arthritis, pleuritis, myocarditis, and septicemia in calves
What is hyperkalemic periodic paralysis in a horse - CORRECT ANSWER --a genetic disorder that affects
muscles causing episodes of muscle weakness or paralysis.
-It is autosomal dominant
What is the cause of hyperkalemic periodic paralysis - CORRECT ANSWER -THe disorder is caused by a
mutation in the sodium channel gene, leading to increased potassium levels in the blood. This affects the
electrical activity of muscle cells, causing the muscles to contract abnormally
What are symptoms of hyperkalemic periodic paralysis in horses - CORRECT ANSWER --muscle twitching
or trembling
,-weakness or partial paralysis especially in hindquarters
-episodes of muscle stiffness
-respiratory issues in severe cases
-horse remains alert
what are triggers of hyperkalemic periodic paralysis - CORRECT ANSWER --high potassium intake from
feed such as alfalfa, molasses or certain grains
-stress, exercise or fasting
how would you manage hyperkalemic periodic paralysis - CORRECT ANSWER --dietary modification like
feeding low potassium diets and aoiding alfala and monitor potassium intake
-medicate with acetazolamide and hydrochlorothiazide
-consistent exercise and minimize stress
A 3-year old Percheron mare is undergoing routine dental evaluation. Physical examination shows bilateral
prolapse of the nictitating membrane and muscle fasciculations of the neck, shoulders, and flank. During
examination, the mare's hindlimbs give way, and she leans back in a dog-sitting posture. Rectal temperature is
100.4 degrees F (38.0 degrees C), heart rate is 60 beats/min, and respiratory rate is 30 breaths/min.
Which of the following is the most likely diagnosis?
A) Equine degenerative myeloneuropathy
B) Equine motor neuron disease
C) Exertional rhabdomyolysis
D) Hyperkalemic periodic paralysis
E) Tetanus - CORRECT ANSWER -D) hyperkalemic periodic paralysis
HYPP leads to episodes of periodic muscle weakness or paralysis.
, -Prolapse of the nictitating membrane is characteristic of HYPP due to muscle weakness in the face
-Weakness and collapse suggest muscle paralysis or severe weakness, dog sitting posture strongly supports this
A 3-year old Percheron mare is undergoing routine dental evaluation. Physical examination shows bilateral
prolapse of the nictitating membrane and muscle fasciculations of the neck, shoulders, and flank. During
examination, the mare's hindlimbs give way, and she leans back in a dog-sitting posture. Rectal temperature is
100.4 degrees F (38.0 degrees C), heart rate is 60 beats/min, and respiratory rate is 30 breaths/min.
This is a case of HYPP, why would Equine Degenerative Myeloneuropathy be incorrect - CORRECT
ANSWER -EDM is a neurodegenerative disease that causes progresse ataxia ( incoordination) and weakness
in young horses, particularly those deficient in vitamin E.
Although it causes weakness, EDM is more associated with ataxia ( uncoordinated movement) rather than
acute muscle fasciculations or prolapse of the nictitating membrane. It is a chronic, progressive condition,
unlike the episodic nature of HYPP
A 3-year old Percheron mare is undergoing routine dental evaluation. Physical examination shows bilateral
prolapse of the nictitating membrane and muscle fasciculations of the neck, shoulders, and flank. During
examination, the mare's hindlimbs give way, and she leans back in a dog-sitting posture. Rectal temperature is
100.4 degrees F (38.0 degrees C), heart rate is 60 beats/min, and respiratory rate is 30 breaths/min.
This is a case of HYPP, why would Equine Motor Neuron Disease be incorrect - CORRECT ANSWER -
EMND is a neurodegeneratie disorder and is associated with vitamin E deficiency
-EMND causes muscle atrophy and weakness, primarily affecting posture and gait over time. However it does
not typically cause acute episodes of weakness with fasciculation and prolapse of the third eyelid like HYPP
does. EMND is also more chronic in its progression, not episodic.
A 3-year old Percheron mare is undergoing routine dental evaluation. Physical examination shows bilateral
prolapse of the nictitating membrane and muscle fasciculations of the neck, shoulders, and flank. During
examination, the mare's hindlimbs give way, and she leans back in a dog-sitting posture. Rectal temperature is
100.4 degrees F (38.0 degrees C), heart rate is 60 beats/min, and respiratory rate is 30 breaths/min.
