Pure red cell aplasia in a Holstein calf

A 3-month-old Holstein calf presented with lethargy. Hematological examination showed severe non-regenerative anemia without reduction in white blood cell and platelet counts. Serum biochemical analysis revealed both high erythropoietin activity and high serum iron concentration. Bone marrow examination revealed selectively decreased erythroid precursors and an increased myeloid:erythroid ratio of 7:1. Lesions that could have caused anemia were found only in bone marrow by necropsy. The calf was diagnosed with pure red cell aplasia (PRCA) based on these clinical and pathological findings. Although the cause of PRCA was not identified, this is the first confirmed clinical report of PRCA in a Holstein calf.