Morphological,cytochemical, and biochemical observations on the blood of the tuatara,Sphenodon punctatus

Abstract

Morphological features of the circulating blood cells of an adult female tuatara are described and illustrated. Mitosis in circulating erythrocytes and the occurrence of an intraerythrocytic haemogregarine parasite are noted. The packed cell volume (haematocrit) was 35%. There were about 310 000 erythrocytes and 7200 leucocytes per mm³ of blood. The lymphocyte was the predominant leucocyte, followed by the eosinophil, monocyte, neutrophil, and basophil. The eosinophils and neutrophils reacted positively to acid phosphatase and peroxidase; the neutrophils were also esterase positive, and all three granulocytes were PAS positive. Haemoglobin, plasma protein, glucose, sodium, potassium, cholesterol, and triglyceride levels were determined. The primitive nature of the tuatara is reflected in the morphological. mensural, and biochemical data presented.