Normal hematologic values of various age groups of Calomys callosus (Rodentia Cricetidae).

Hematologic values for Calomys callosus, a wild rodent, were established. Males and females from a colony raised in Animal Housing of the Institute of Tropical Medicine of São Paulo were examined individually. For the red blood cell series, the number of erythrocytes, hemoglobin concentration, hematocrit, and platelet and reticulocyte numbers were measured. All values except hemoglobin concentration were slightly higher in aged animals than in young animals. The white blood cell series had a predominance of lymphocytes, with no age-associated changes.