Evaluation of blood erythroid parameters in male broiler chickens (Ross 308) with the Sysmex XT-2000iV and Sysmex XN-1000V analyzers and determination of hematological reference intervals obtained with manual and instrumental methods.

Abstract

BACKGROUND: The presence of both nucleated RBC and thrombocytes in birds makes the determination of hematological variables difficult. This leads to time-consuming manual evaluation. New-generation analyzers are hypothesized to be both time-saving and accurate. OBJECTIVES: The objective was to evaluate the performance of two hematology analyzers in 27-day-old broilers and to establish reference intervals (RIs) for RBC and WBC variables obtained by automated and manual methods. METHODS: Automated HCT, WBC count, and differentials obtained using Sysmex XT-2000iV and XN-1000V on 309 and 56 EDTA blood samples from Ross 308 male broilers, respectively, were compared to manual PCV, manual WBC count, and differentials from November 2021 to November 2022. RIs for automated HCT and RBC variables (from impedance channel) on one hand, and manual PCV and WBC's variables on the other hand, were established. RESULTS: The Sysmex XT-2000iV was accurate for HCT and outperformed the XN-1000V but, both automated methods and manual methods cannot be considered interchangeable. Constant error, proportional error, and bias were identified and calculated for each analyzer for HCT. Both analyzers were unable to enumerate WBC. RIs were established as follows: HCT-XT (L/L) [0.27-0.36]; HCT-XN (L/L) [0.24-0.38]; manual PCV (L/L) [0.27-0.37]; manual WBC (×10/L) [10.0-38.4]; manual differential (×10/L) with heterophils [1.5-16.2]; lymphocytes [5.1-18.9]; monocytes [0.0-2.1]; eosinophils [0.0-2.2]; basophils [0.0-3.1]. CONCLUSIONS: Both analyzers are usable for the evaluation of HCT in Ross 308 chickens and in specific conditions for the other RBC variables. Manual methods are still preferred for the evaluation of WBC variables.