What is the purpose of performing a differential leukocyte count?

Performing a differential leukocyte count serves the specific purpose of identifying the proportions of different types of white blood cells in a sample. This test is critical in diagnosing and monitoring various conditions, including infections, inflammatory diseases, and hematologic disorders. Each type of white blood cell has distinct functions and can respond differently to various pathologies. By assessing the relative amounts of each cell type, veterinarians and medical professionals can glean valuable insights into a patient’s immune response and underlying health issues.

The other options reflect different blood tests that serve separate purposes. Evaluating overall blood glucose levels refers to a specific test for monitoring diabetes and metabolic functions. Measuring hemoglobin levels pertains to assessing an animal's oxygen-carrying capacity, which is crucial for diagnosing anemia and other blood disorders. Determining blood plasma volume relates to fluid balance and hydration status rather than the immune response, which is the focus of a differential leukocyte count. Each of these tests provides important information, but only the differential leukocyte count directly assesses the variety and proportions of white blood cells in the blood.