Reference Values for the Bone Marrow Aspirates in Adult Dogs

Abstract

Reference ranges for each cell type and six different ratios (M : E ratio = quotient of number of myeloid cells/erythroid precursors; different maturation ratios) were calculated for bone marrow aspirates of adult dogs. These values were based on 2.5 and 97.5% percentiles of differentials of 1000 cells in bone marrow aspirates of 92 healthy 1-8-year-old dogs. The results of intact male and female dogs were compared. No distinct sex-related differences were found (P > 0.05). A wide physiological range was observed in almost all bone marrow cells resulting in broad reference ranges for the ratios. The clinically relevant M : E ratio varied between 0.45 and 2.87. The accurate cytological examination of bone marrow based on the reference ranges presented in this study requires preparation of high-quality bone marrow films with minimal blood contamination.

Automated hematologic analysis of bone marrow aspirate samples from healthy Beagle dogs

“…However, as much of the variability in bone marrow smear composition may reside in acquisition technique, it was considered useful to statistically analyze the results obtained. In general, similar differential counts were obtained to those reported in several previous studies . One study identified fewer granulocytic cells and a lower GE ratio in bone marrow from dogs of a wider range of ages .…”

“…In general, similar differential counts were obtained to those reported in several previous studies. 1,18,21 One study identified fewer granulocytic cells and a lower GE ratio in bone marrow from dogs of a wider range of ages. 1 This may reflect a wide range of hematopoietic activity in healthy animals and differences in technique, and emphasizes the importance of interpreting BM in relation to peripheral blood and clinical findings.…”

“…Subsequent evaluation by a pathologist yields a semi‐quantitative and qualitative interpretation, which may include differential cell counting, calculation of ratios of cell types, and assessment of boney trabeculae, iron, vascular, and other BM constituents. Differential counting of 100–1,000 cells, depending on the desired accuracy, has been suggested in some instances, while estimation of the different cellular components and interpretation of hematopoietic activity in relation to peripheral blood findings appear to be common practice in other settings …”

“…Differential counting of 100-1,000 cells, depending on the desired accuracy, has been suggested in some instances, while estimation of the different cellular components and interpretation of hematopoietic activity in relation to peripheral blood findings appear to be common practice in other settings. [1][2][3] Automated analysis could potentially provide similarly fast and objective characterization of cells in BM aspirates as in peripheral blood. As BM is composed of different hematopoietic cell types that may have similar light scatter and biochemical properties as their mature counterparts in blood, automated hematology analyzers might also recognize RBC and WBC precursors in BM.…”

“…We hypothesized that routinely collected anti-coagulated BM samples from dogs may be analyzed in the Advia 2120 hematology analyzer and that variables from such analysis would be qualitatively and quantitatively similar to microscopically identified cell populations in BM. Hence, the objectives of this study were to (1) examine the practicability of analyzing BM aspirate samples in the Advia 2120; (2) determine if results of automated analysis correlate with cytologic smear assessment; and (3) establish descriptive summary statistics of cell populations for BM aspirates from hematologically normal and clinically healthy Beagle dogs.…”