Laboratory Procedures Flashcards

Which anticoagulant is found in a purple-top (lavender) tube and is used for complete blood counts?

Answer: EDTA

EDTA (ethylenediaminetetraacetic acid) chelates calcium and is the anticoagulant of choice for CBCs because it preserves cell morphology.

A urine specific gravity of 1.008–1.012 in a dog is classified as:

Answer: Isosthenuria

Isosthenuria refers to urine specific gravity in the range of 1.008–1.012, which is similar to glomerular filtrate and indicates inadequate concentrating or diluting ability.

When performing a blood smear, the feathered edge is used to evaluate:

Answer: Platelet clumps and large cells

The feathered edge of a blood smear is where platelets tend to clump and large cells such as monocytes accumulate, making it an important area to scan.

Which stain is used to identify reticulocytes in a peripheral blood smear?

Answer: New methylene blue stain

New methylene blue is a supravital stain that precipitates residual RNA in reticulocytes, making them identifiable as cells with blue granular network.

A sample for blood glucose measurement is collected in a gray-top tube. What additive does it contain?

Answer: Sodium fluoride and potassium oxalate

Gray-top tubes contain sodium fluoride (a glycolytic inhibitor) and potassium oxalate (an anticoagulant), preserving glucose levels for accurate measurement.

On a urinalysis, which finding is considered NORMAL in small animals?

Answer: Occasional hyaline casts (0–2/lpf)

Occasional hyaline casts (0–2 per low-power field) can be a normal finding, as they form from Tamm-Horsfall protein secreted by tubular cells.

Which QC procedure should be performed each time a new lot of reagent strips is opened for urinalysis?

Answer: Run positive and negative control solutions

Running both positive and negative controls verifies that the new reagent strip lot is performing correctly before patient samples are tested.