Changes of hematological references depends on storage period and temperature conditions in rats and dogs.

Because changes in rat and dog hematological parameters according to storage conditions have been poorly documented, we sought to examine such changes. Blood analysis was performed using two hematology analyzers (ADVIA 2120 and Sysmex XN-V) after storage at room temperature and in cold storage for 5, 24, and 48 h, respectively. Interassay coefficients of variation for hematological parameters analyzed with the ADVIA 2120 and the XN-V showed similar. The levels of hematocrit, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, and platelet (PLT) showed significant variations with time in blood samples of rats and dogs. The leukocyte subpopulation showed high variation with storage conditions. The data for leukocyte differential counts obtained using the ADVIA 2120, XN-V, and a manual differential counting procedure showed good agreement for neutrophils and lymphocyte counts, but monocytes, eosinophils, and basophils showed differences between the procedures. In conclusions, most rat and dog hematological parameters showed minimal changes; however, some showed high variation with storage time and temperature, especially PLT and leukocyte subpopulations. In conclusion, when performing hematological analysis in dogs and rats, it will be exactitude to analyze blood samples in fresh condition and at least within 24 h in the cold storage.