The short answer
This guide holds 12 original practice questions on veterinary laboratory procedures, written by our desk for exam preparation. They are not real VTNE items. The questions are grouped into three areas: hematology and blood sample handling, urinalysis, and fecal parasitology. Each answer comes with a short rationale tied to a cited reference. The fetched AAVSB page confirms that the VTNE has a published content outline and 10 domain areas, but it does not state the name or weight of any individual domain.
Key takeaways
- The Merck Veterinary Manual states that blood for hematology should be collected into EDTA and mixed immediately to prevent clotting [2].
- Merck notes that a hemolyzed sample shows a lower PCV with unchanged hemoglobin, which produces a falsely high MCHC [2].
- According to Merck, urine that cannot be examined within 30 minutes may be refrigerated for up to 24 hours, which may precipitate crystals but does not change pH or specific gravity [3].
- Today's Veterinary Practice reports that the dipstick pads for specific gravity, urobilinogen, nitrite and leukocytes are not used for veterinary patients [9].
- Merck describes zinc sulfate centrifugal flotation (specific gravity 1.18) as the best option for detecting Giardia duodenalis cysts in small animals [4].
- Per Merck, Baermann examination is the method of choice for nematode larvae and simple sedimentation is the method of choice for operculate eggs [4].
About these questionsPractice questions written by our editorial team for study purposes. These are not real VTNE items and are not affiliated with AAVSB.
Laboratory procedures on the VTNE
The AAVSB describes its content outline as "one of the most important materials to review" before the exam [1]. According to the AAVSB study page, the exam covers 10 domain areas, and the organization sells three versions of an online practice test, each with 75 questions over 90 minutes at $50 USD per attempt [1]. The fetched page does not list the domain names or the share of the exam assigned to laboratory work, so this guide does not state a weight. The AAVSB says the species covered follow the AVMA accreditation list of essential and recommended student skills [1].
Hematology and blood sample handling
Question 1
A technician is collecting blood from a dog for a complete blood count. Which tube additive does the Merck hematology chapter specify for this sample?
- A. Fluoride/oxalate
- B. EDTA
- C. Citrate
- D. No additive (plain serum tube)
Answer: B. The Merck Veterinary Manual says hematology samples go into EDTA and should be mixed at once to avoid clotting [2]. Merck lists fluoride/oxalate plasma for glucose measurement [5], and Today's Veterinary Nurse describes citrated plasma as the sample for coagulation studies [8].
Question 2
PCV, hemoglobin concentration and RBC count are measured routinely. Which two indices can be calculated from them?
- A. MCV and platelet count
- B. RBC count and PCV
- C. MCV and MCHC
- D. Hemoglobin and WBC count
Answer: C. Merck explains that because the three red cell measurements vary in relation to each other, they allow calculation of mean corpuscular volume (MCV) and mean corpuscular hemoglobin concentration (MCHC) [2].
Question 3
When a manual blood smear is made, at what angle does the spreader slide sit in front of the blood drop?
- A. 5 to 10 degrees
- B. 60 to 70 degrees
- C. 85 to 90 degrees
- D. 30 to 40 degrees
Answer: D. Today's Veterinary Nurse describes holding the spreader slide at a 30 to 40 degree angle, adjusted as needed, and pushing it forward in one smooth motion without changing the angle [6].
Question 4
A blood sample arrives at the laboratory markedly hemolyzed. Which artifactual result does the Merck hematology chapter associate with hemolysis?
- A. Falsely high MCHC
- B. Falsely low MCHC
- C. Falsely high PCV
- D. Falsely low hemoglobin
Answer: A. Merck states that hemolysis lowers the PCV while hemoglobin stays the same, "again leading to a falsely high MCHC" [2].
Urinalysis
Question 5
A cystocentesis sample cannot be examined within 30 minutes and is refrigerated for several hours. Which change does Merck list as a possible consequence of refrigeration?
- A. A rise in urine pH
- B. Crystal precipitation
- C. A falsely low specific gravity
- D. A falsely high specific gravity
Answer: B. According to Merck, urine may be refrigerated for up to 24 hours, but this may result in crystal precipitation, and refrigeration does not alter urine pH or specific gravity [3].
Question 6
Which reagent strip test pad is considered valid for routine use on a canine urine sample?
- A. Nitrite
- B. Leukocyte esterase
- C. Specific gravity
- D. Glucose
Answer: D. Merck lists glucose among the routine dipstick tests and says the leukocyte esterase, nitrite and specific gravity pads are not valid in animals [3]. Today's Veterinary Practice gives the same list of pads not used in veterinary patients, adding urobilinogen [9].
Question 7
A dog's urine has an alkaline pH. Which crystal type does Merck describe as forming in alkaline urine?
- A. Struvite
- B. Cystine
- C. Ammonium acid urate
- D. The picket-fence form of calcium oxalate seen with ethylene glycol toxicity
Answer: A. Merck states that struvite forms in alkaline urine, while cystine and ammonium acid urate crystals occur in acidic urine and the ethylene glycol-associated calcium oxalate form is found in neutral to acidic urine [3].
Question 8
Sediment from a cat's urine shows an average of 3 red blood cells per high-power field across 10 fields. How does this count compare with published expectations for healthy animals?
- A. It indicates marked hematuria
- B. It meets the definition of pyuria
- C. It falls within the number that may be present in healthy animals
- D. It confirms renal cast formation
Answer: C. Today's Veterinary Practice reports that up to 5 red blood cells per high-power field may be present in healthy animals, with elements averaged over 10 fields [9]. Merck similarly states that normal urine should contain fewer than 5 RBCs per field at 400x [3].
Fecal parasitology
Question 9
Which fecal examination method does Merck consider the best option for detecting Giardia duodenalis cysts in small animals?
- A. Baermann examination
- B. Simple sedimentation
- C. Modified Knott's test
- D. Centrifugal flotation with zinc sulfate
Answer: D. Merck names centrifugal flotation using zinc sulfate (specific gravity 1.18) as "the best option for detecting Giardia duodenalis cysts" [4]. The modified Knott's test is a blood test for microfilariae [4].
Question 10
A cat with respiratory signs is suspected of having Aelurostrongylus abstrusus infection. Which fecal method does Merck describe as the method of choice?
- A. Simple flotation with zinc sulfate
- B. Baermann examination
- C. Modified Knott's test
- D. Urine sediment examination
Answer: B. Merck identifies the Baermann examination as the method of choice for nematode larvae, including cardiorespiratory infections caused by A. abstrusus in cats [4].
Question 11
Paragonimus kellicotti is suspected in a dog. Which method does Merck describe as the method of choice for the operculate eggs of trematodes such as this one?
- A. Simple sedimentation
- B. Centrifugal flotation
- C. Baermann examination
- D. Heartworm antigen test
Answer: A. Merck says operculate eggs are not reliably detected by flotation and that simple sedimentation is the method of choice for trematodes including P. kellicotti [4].
Question 12
A sedimentation is being set up for a dog suspected of infection with the blood fluke Heterobilharzia americana. Which liquid does Merck specify for the procedure?
- A. Tap water
- B. Hot tap water
- C. Saline solution
- D. Zinc sulfate flotation solution
Answer: C. Merck states that saline must replace water for this procedure, because water causes the eggs to hatch and the released miracidia are poured off with the supernatant, producing false-negative results [4].
