Retrospective and observational investigation of canine microcytosis in relationship to sex, breed, diseases, and other complete blood count parameters

The prevalence of canine microcytosis, detected as reduced mean corpuscolar volume (MCV) by impedance cell counter was investigated retrospectively in relationship to sex, breed, diseases, and other blood count parameters. One thousand and twelve (1,012) canine medical records with complete blood count (CBC) were evaluated for MCV results. CBCs were performed using impedance cell counter and stained blood smears for leukocyte differential count, erythrocyte morphology, and platelet estimation. Statistical analysis included both comparative and descriptive investigations in dogs showing microcytosis (MICRO) versus dogs with normal MCV (control, CTR). MCV was lower than the reference range in 8. 5% of medical records (86/1,012). Only 47. 7% of MICRO dogs were affected by different degrees of anemia. In MICRO dogs, thrombocytosis was present in 19. 8%, while 16. 3% showed thrombocytopenia, and mild leukocytosis was found in 30. 2%. Statistical analysis showed significant difference about sex and breeds in MICRO vs. CTR dogs while different disorders did not affect the MICRO vs. CTR dogs; few CBC parameters such as erythrocyte count, hematocrit, and red cell dimension width were both significantly related to MCV of MICRO dogs and between CTR and MICRO dogs. Multivariate hierarchical cluster analysis showed significant difference among clusters considering platelets and displayed a subgroup of patients in MICRO dogs. Microcytosis detected at low rate in CBC of clinical records is not always related to anemia. The comparison in MICRO and CTR dogs showed a significant difference for most blood count parameters dealing with erythrocytes and leukocytes but not for platelets.