Hematology of Raptors

Sample sites for blood collection in raptor species vary with patient size and potential use of sedation or anesthesia. The medial metatarsal vein, cutaneous ulnar vein, basilic vein, and jugular vein are common peripheral blood collection sites. As with other nonmammalian species, avian hematologic methods generally rely on manual counting of white blood cells and thrombocytes. Thrombocytes can generally be distinguished from lymphocytes by their clear to pale blue cytoplasm, oval to slightly elongated nuclei, and smaller nuclear size. Many reference intervals used for raptors were not created in accordance with American Society for Veterinary Clinical Pathology guidelines and medical care may be affected. Reference intervals for PCV in raptor species vary with age. Stress leukograms are occasionally reported in raptors and are similar to corticosteroid-mediated stress leukograms in mammals, with heterophilia and lymphopenia noted. A variety of blood-sucking arthropods serve as biological vectors for different Trypanosoma species.