You may not like needles or giving blood when you go to the doctor’s office, but did you know that blood is an important diagnostic tool for veterinarians? When an animal is feeling sick, one of the very first steps in a veterinarian’s diagnosis (i.e., the process of identifying the cause of a patient’s disease) and treatment process is often to obtain a blood sample for analysis. When examined under a microscope, a tiny drop of blood can provide a wealth of information about an animal’s disease status.
Hematology, which is used commonly in both human and veterinary medicine, refers to the process of analyzing blood, including using a microscope. For this diagnostic technique, a “blood smear” is prepared: a tiny drop of blood is spread to a thin, single-cell layer on a microscope slide. This allows the veterinarian to observe the animal’s blood cells on high magnification with a microscope to determine whether they are healthy. This is done by evaluating the number of cells, as well as cell shape and color (or “morphology”).