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tvpjournal.com | July/August 2015 | TodAy's VeTerinAry PrAcTice in-cLinic HeMAToLoGy Peer reviewed 47 absence of a regenerative response or obvious sepsis or hyperthermia—indicate that a pathologist should evaluate the blood flm. Typically, these are metarubricytes, though earlier precursors can sometimes be observed. Inclusions that may be present: • Howell-Jolly bodies, dense, round purple inclusions, which are common and represent retained nuclear material normally observed in cats, or associated with increased red cell turnover or decreased splenic function. • Red cell parasites, which may appear as pyriform (Babesia species), flat, or round inclusions on the cell surface that may detach with time if smears are not prepared immediately after sample collection (Mycoplasma species) (Figure 12). • Viral inclusions, such as those occasionally seen in the acute phase of canine distemper, which are rare but diagnostically invaluable (Figure 13). White Blood Cells Morphologic observations of white blood cells (WBcs) are made while performing a 100-cell differential cell count at high magnifcation within the counting area. Toxic change of neutrophils is a common and diagnostically critical morphologic abnormality indicative of infammation that may be observed even with normal cell counts (Figure 14). common components include cytoplasmic basophilia, vacuolization, and presence of döhle bodies—small irregular inclusions that, in small numbers, can be present in healthy cats. Left shift indicates the presence of granulocyte precursors, mostly band forms in which nuclear segmentation is incomplete (Figure 15). Left shift often occurs along with toxic change, which indicates the release of granulocyte precursors due FIGURE 13. Distemper inclusions in RBCs ( arrows ) and neutrophils ( arrowheads ) are displayed. This example shows distemper inclusions visible in both Wright-Giemsa (A) and Diff-Quik (B) stained samples. The inclusions stain more faintly on the Wright-Giemsa stain than the Diff-Quik stain. Be aware that distemper inclusions are more easily visible with Diff-Quik preparations, and can be extremely diffcult to identify in Wright's-Giemsa stained preparations due to poor staining characteristics. Magnifcation, 1000×. A B FIGURE 14. WBC morphology: Toxic change revealed in 2 segmented neutrophils; toxic change appears as increased cytoplasmic basophilia, foaminess, and Döhle bodies (arrows). Wright-Giemsa stain; magnifcation, 1000×. FIGURE 15. WBC morphology: Two band neutrophils that exhibit toxic change. Wright- Giemsa stain; magnifcation, 1000×. View images of normal leukocyte morphology by visiting the American Society for veterinary Clinical Pathology's website (asvcp .org): Click on the Students/ Residents tab and select "Download visual hematology Guide — leukocytes as a PDF fle" from the new page that opens. V i e