Cytology of Turkey Blood-Reactive Hemograms and Measures of Stress

Abstract

The current study was intended to offer a cytological counterbalance to published descriptions of how processing or other procedures affect turkey welfare. Cytology represents a detailed description of morphological atypia or unusual intracellular or intercellular behavior. The study aimed to describe the variation of blood cells of commercial turkeys. Blood films were collected from 4 turkeys at four different ages of 6, 12, 17, and 19 weeks at commercial farms by a qualified veterinarian. The slides, stained by Wright-Giemsa, were photographed and interpreted off-site. Normal cells of the lymphocyte (L) and heterophil (H) series were described first, followed by examples of atypical cells of other series. These were shown with descriptions of cellularity defined as the proportion of leukocytes in each microscopic field. The results indicated examples of cells whose presence in a standard differential count (SDC) was important enough to disqualify the simple H/L ratio as a stress measure. These cells were atypical members of the lymphoid series, plasmacytes, and other cell types. Atypical granulocytes were heterophils with irregular shapes and faint nuclear staining (hypochromia). An example of a representative total white count revealed how the H/L value could depend on where the cells were counted on the slide. In conclusion, the cytology clearly shows that the presence of atypical cells in a hemogram highlights the inadequacy of relying solely on the simple H/L ratio to estimate stress status.