Evaluation of an in-house centrifugal hematology analyzer for use in veterinary practice.

This research paper compares the results of Complete Blood Count (CBC) tests administered to several species of animals using a centrifugal analyzer with those obtained from a traditional reference method. The results indicate that while there was a strong correlation for some elements in different species, the inability of the centrifugal analyzer to identify abnormal cells, along with a high error rate for samples with irregular White Blood Cell counts, prohibits its standalone use for differential cell counts.

Research Methodology

• For this study, blood samples were collected from a variety of animals (147 dogs, 42 cats, 60 horses, and 24 cows) admitted to a veterinary teaching hospital or a commercial dairy herd.
• The results by a centrifugal analyzer were compared against an established reference method, which involved an electrical-impedance light-scatter hematology analyzer and a manual differential cell count.

Findings

• The centrifugal analyzer produced error messages in 50 out of 273 samples, accounting for an 18% error rate. The errors were more frequent in samples with values outside of the established reference ranges.
• Correlation coefficients varied widely depending on the blood component and species being analyzed. For example, the correlation for Haematocrit (Hct) ranged from 0.80 to 0.99, while for total White Blood Cell (WBC) count it ranged from 0.76 to 0.95.
• Correlation for mononuclear cell counts (a combination of lymphocyte and monocyte) varied from 0.56 in cats to 0.92 in cattle.

Conclusions

• According to the results, the centrifugal analyzer showed excellent correlation with the reference method in specific cases only – namely, Hct in cats, dogs, and horses; WBC count in dogs and horses; granulocyte count in dogs and horses; and reticulocyte count in dogs.
• However, the inability of the analyzer to identify abnormal cells, its high error rate specifically for samples with abnormal WBC counts, and the wide confidence intervals, indicate that differential cell counts derived from the centrifugal analyzer cannot be relied upon independently of the reference method.