CVA Laboratory Techniques & Diagnostic Procedures 4 — Questions and Answers
Question 1: A dog's blood glucose is 320 mg/dL. This finding is most consistent with:
- Diabetes mellitus (Correct answer)
- Addison's disease
- Hypoglycemia
- Normal postprandial value
Correct answer: Diabetes mellitus
Normal canine blood glucose is approximately 70–120 mg/dL; a value of 320 mg/dL is significantly elevated, consistent with diabetes mellitus.
Question 2: Which stain is used to identify Mycobacterium species (acid-fast bacteria)?
- Ziehl-Neelsen (acid-fast) stain (Correct answer)
- Gram stain
- Diff-Quik
- PAS stain
Correct answer: Ziehl-Neelsen (acid-fast) stain
Ziehl-Neelsen stain uses carbol fuchsin dye that acid-fast bacteria retain after acid-alcohol decolorization, making them appear red.
Question 3: When centrifuging a blood sample, the buffy coat layer located between the red blood cells and plasma primarily contains:
- White blood cells and platelets (Correct answer)
- Only red blood cells
- Serum proteins
- Plasma electrolytes
Correct answer: White blood cells and platelets
The buffy coat is the thin white layer that forms between packed red cells and plasma, consisting of leukocytes and platelets.
Question 4: A vaginal cytology smear from a dog showing predominantly cornified (anuclear) squamous epithelial cells indicates:
- Estrus (standing heat) (Correct answer)
- Anestrus
- Proestrus
- Diestrus
Correct answer: Estrus (standing heat)
Cornified anuclear squamous cells predominate during estrus due to peak estrogen stimulation of the vaginal epithelium.
Question 5: Which parameter is NOT typically measured in a standard complete blood count (CBC)?
- Blood urea nitrogen (BUN) (Correct answer)
- Red blood cell count
- White blood cell count
- Hemoglobin concentration
Correct answer: Blood urea nitrogen (BUN)
BUN is a chemistry panel value that reflects kidney function; it is not part of the CBC, which evaluates cellular blood components.
Question 6: What is the proper handling of a blood smear immediately after spreading it on a slide?
- Allow it to air dry completely before staining (Correct answer)
- Immediately place it in fixative while still wet
- Refrigerate it before staining
- Cover it with a coverslip right away
Correct answer: Allow it to air dry completely before staining
Blood smears must air dry completely before staining to ensure proper cell morphology and prevent cell distortion.
Question 7: A urine pH of 5.0 in a dog on a high-protein diet is considered:
- Normal and expected (Correct answer)
- Abnormally alkaline
- Indicative of urinary infection
- A sign of kidney failure
Correct answer: Normal and expected
High-protein diets produce acid metabolites that lower urine pH; a pH of 5.0 is normal for dogs consuming high-protein food.
CVA Laboratory Techniques & Diagnostic Procedures 4
A dog's blood glucose is 320 mg/dL.
This finding is most consistent with: