What is the name for a nonnucleated, immature erythrocyte found in small numbers in the peripheral blood of dogs?

What is the name for a nonnucleated, immature erythrocyte found in small numbers in the peripheral blood of dogs?

• A. Reticulocyte
• B. Metarubricyte
• C. Rubriblast
• D. Rubricyte

Answer: (A)

In mammals, the final stage of red blood cell development that can be seen circulating in the blood is a reticulocyte. These cells are immature but nonnucleated, meaning they have shed their nucleus as part of normal maturation. What makes reticulocytes distinctive is that they still contain residual RNA, so they can be visualized with special stains and often look slightly bluish or nealy polychromatophilic on a standard smear. In dogs, small numbers of reticulocytes in peripheral blood are a normal finding. If the reticulocyte count rises (reticulocytosis), it usually means the bone marrow is actively producing new red cells in response to anemia or blood loss. The other stages listed are nucleated precursors that reside in the bone marrow: rubriblast and rubricyte are earlier erythroblast stages, and metarubricyte is a late nucleated stage just before nucleus extrusion. Those are not the nonnucleated immature cells circulating in normal peripheral blood. Therefore, the description fits the reticulocyte best.

In mammals, the final stage of red blood cell development that can be seen circulating in the blood is a reticulocyte. These cells are immature but nonnucleated, meaning they have shed their nucleus as part of normal maturation. What makes reticulocytes distinctive is that they still contain residual RNA, so they can be visualized with special stains and often look slightly bluish or nealy polychromatophilic on a standard smear.

In dogs, small numbers of reticulocytes in peripheral blood are a normal finding. If the reticulocyte count rises (reticulocytosis), it usually means the bone marrow is actively producing new red cells in response to anemia or blood loss. The other stages listed are nucleated precursors that reside in the bone marrow: rubriblast and rubricyte are earlier erythroblast stages, and metarubricyte is a late nucleated stage just before nucleus extrusion. Those are not the nonnucleated immature cells circulating in normal peripheral blood. Therefore, the description fits the reticulocyte best.