Crenation is identified as the presence of many regular membrane projections involving most of the cells. It is usually an artifact due to slow drying of the blood film. It is commonly observed in blood films from pigs, but can also be observed on blood films from normal cats and cattle. Poikilocytes or schistocytes are erythrocytes having an abnormal shape. Schistocytes are observed in fragmentation hemolysis caused by DIC, vascular neoplasia, endocarditis, and may also be observed with iron deficiency anemia.
Acanthocytes are erythrocytes having irregular projections from the surface.
They have been observed in dogs and cats with severe liver disease and are probably the result of alteration of lipid content of the red cell membrane. Target Cells and Folded Cells . These are two types of leptocytes observed mainly in dogs. The change is not specific for any particular disease. A target cell and a folded cell are seen in the center.