A veterinary technician counts leukocytes in four areas, sums them, and multiplies by 50 to obtain the leukocyte count. If the counts are 23, 27, 28 and 34, what is the correct leukocyte count?

• A. 5800 leukocytes
• B. 5900 leukocytes
• C. 5600 leukocytes
• D. 5700 leukocytes

Answer: (C)

Estimating leukocyte concentration with a hemocytometer involves counting cells in four small squares, adding those counts, and then multiplying by a factor to scale to a per-microliter value. The factor 50 comes from the known volume that those four squares represent, converting the summed counts into cells per microliter.

Add the four counts: 23 + 27 + 28 + 34 = 112. Multiply by 50: 112 × 50 = 5600.

So the leukocyte count is 5600 leukocytes per microliter. This aligns with the standard method where the sum of counts in the four squares is scaled by 50 to yield the concentration.