Final answer:
To estimate the hemoglobin concentration in canine blood, divide the PCV by 3. For a patient with a hematocrit of 42%, approximately 58% of their blood is plasma.
Step-by-step explanation:
To estimate the hemoglobin concentration in the blood of a canine, you would divide the PCV (packed cell volume) by 3. So the correct answer to the question is d. 3. This is a rough estimate used in veterinary practice to get a quick idea of the hemoglobin levels; it assumes that each dl (deciliter) of PCV equates to approximately 3 g of hemoglobin. For example, if a dog's PCV is 45%, dividing this number by 3 would give an estimated hemoglobin concentration of 15 g/dl.
CRITICAL THINKING QUESTIONS: If a patient's hematocrit is 42 percent, approximately 58 percent of the patient's blood is plasma (because hematocrit represents the percentage of blood volume occupied by red cells).